STOCK RADAR
Filed
SLNSilence Therapeutics plcNasdaq

Registers $300M universal shelf; $100M ADS ATM with Jefferies

S-3Dilution RiskbearishImpact90

SLN Price

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N/A$0.00 (+0.00%)
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The shelf and ATM enable primary issuances that could substantially increase tradable supply and exert downward price pressure

Silence Therapeutics filed an S-3 registering a $300,000,000 universal shelf and a Jefferies ADS ATM for up to $100,000,000. The filing discloses 141,703,840 ordinary shares outstanding but not share-equivalents

Score90

Score Rationale

bearish

Shelf plus $100M ADS ATM, offering exceeds market cap

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SLN Market Context

Market Cap$277.26M
Shares Outstanding47.23M
Public Float37.67M
Public Float %79.7%
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Original Filing Text

SEC filing text preserved from the raw item store.

### S-3 - S-3
S-3
1
d120718ds3.htm
S-3

S-3

As filed with the Securities and Exchange Commission on May 18, 2026.

Registration Statement No. 333-

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM S-3

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

SILENCE THERAPEUTICS PLC

(Exact name of Registrant as specified in its charter)

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England and Wales |
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Not applicable |

(State or other jurisdiction of
incorporation or organization) |
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(I.R.S. Employer
Identification Number) |

12 Hammersmith Grove

London W6 7AP
United
Kingdom
Tel: +44 20 3457 6900

(Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices)

Silence Therapeutics Inc.

221 River Street, 9th Floor

Hoboken, New Jersey 07030

Tel: +1 908 938 4221

(Name, address, including zip code, and telephone number, including area code, of agent for service)

Copies to:

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Courtney T. Thorne

Divakar Gupta
Eric
Blanchard
Cooley LLP
55 Hudson Yards
New York, New York 10001
+1 212 479 6000
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Claire A. Keast-Butler

Cooley (UK) LLP
22
Bishopsgate
London EC2N 4BQ

United Kingdom
+44 20 7583
4055
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From time to time after the effective date of this registration statement

(Approximate date of commencement of proposed sale to the public)

If the only securities being registered on this Form are being offered pursuant to dividend or interest reinvestment plans, please check the following
box. ☐
If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under
the Securities Act of 1933, check the following box. ☑
If this Form is filed to register additional securities for an offering pursuant to
Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act
registration statement number of the earlier effective registration statement for the same offering. ☐
If this Form is a registration
statement pursuant to General Instruction I.D. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box. ☐

If this Form is a post-effective amendment to a registration statement filed pursuant to General Instruction I.D. filed to register additional securities or
additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box. ☐
Indicate by check mark whether
the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated
filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

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Large accelerated filer |
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Accelerated filer |
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Non-accelerated filer |
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Smaller reporting company |
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Emerging growth company |
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If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period
for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act. ☐

The Registrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the Registrant shall
file a further amendment which specifically states that this registration statement shall thereafter become effective in accordance with section 8(a) of the Securities Act or until the registration statement shall become effective on such date as
the Securities and Exchange Commission acting pursuant to said section 8(a), may determine.

EXPLANATORY NOTE

This Registration Statement of Silence Therapeutics plc, or the Company, contains two prospectuses:

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a base prospectus, which covers the offering, issuance and sale by the Company of the securities identified
therein from time to time in one or more offerings up to a total aggregate offering price of $300,000,000; and
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a sales agreement prospectus, which covers the offering, issuance and sale by the Company of up to a maximum
aggregate offering price of $100,000,000 of the American Depositary Shares, or ADSs, each representing three ordinary shares of the Company that may be issued and sold under an Open Market Sale
Agreement SM with Jefferies LLC, dated May 18, 2026, between the Company and Jefferies LLC.
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The base prospectus immediately follows this explanatory note. The specific terms of any securities to be offered pursuant to the base prospectus will be
specified in one or more prospectus supplements to the base prospectus. The sales agreement prospectus immediately follows the base prospectus. The $100,000,000 of ADSs that may be offered, issued and sold by the registrant under the sales agreement
prospectus is included in the $300,000,000 of securities that may be offered, issued and sold by the registrant under the base prospectus. Upon termination of the sales agreement with Jefferies LLC, any portion of the $100,000,000 included in the
sales agreement prospectus that is not sold pursuant to the sales agreement will be available for sale in other offerings pursuant to the base prospectus and a corresponding prospectus supplement, and if no shares are sold under the sales agreement,
the full $100,000,000 of securities may be sold in other offerings pursuant to the base prospectus and a corresponding prospectus supplement.

The information in this preliminary prospectus is not complete and may be changed. We may not sell these securities until the registration
statement filed with the Securities and Exchange Commission is effective. This preliminary prospectus is not an offer to sell these securities and it is not soliciting an offer to buy these securities in any state where the offer or sale is not
permitted.

Subject to Completion, dated May 18, 2026

PROSPECTUS

SILENCE THERAPEUTICS PLC

$300,000,000
Ordinary
Shares
(including Ordinary Shares Represented by American Depositary Shares)

From time to time, we may offer and sell up to $300,000,000 of our ordinary shares. Our ordinary shares may be represented by American Depositary Shares, or
ADSs. Each ADS represents three ordinary shares of the Company.
This prospectus describes the general terms of these securities and the general manner in
which these securities will be offered. We will provide the specific terms of these offerings in one or more supplements to this prospectus. We may also authorize one or more free writing prospectuses to be provided to you in connection with these
offerings. The prospectus supplement and any related free writing prospectus may also add, update or change information contained in this prospectus. You should carefully read this prospectus, the applicable prospectus supplement and any related
free writing prospectus, as well as any documents incorporated by reference, before you invest.
Securities may be sold directly to investors, through
agents designated from time to time or to or through underwriters or dealers, on a continuous or delayed basis. For additional information on the methods of sale, you should refer to the section titled “Plan of Distribution” in this
prospectus and in the applicable prospectus supplement. If any underwriters or agents are involved in the sale of our securities with respect to which this prospectus is being delivered, the names of such underwriters or agents and any applicable
fees, commissions or discounts and over-allotment options will be set forth in a prospectus supplement. The price to the public of such securities and the net proceeds that we expect to receive from such sale will also be set forth in a prospectus
supplement.
The ADSs representing our ordinary shares are listed on The Nasdaq Global Market, or Nasdaq, under the symbol “SLN.” On May 15,
2026, the closing price of the ADSs on The Nasdaq Global Market was $6.10 per ADS. The applicable prospectus supplement will contain information, where applicable, as to other listings, if any, on The Nasdaq Global Market or other securities
exchange of the securities covered by the applicable prospectus supplement. Prospective purchasers of our securities are urged to obtain current information as to the market prices of our securities, where applicable.

We are a “smaller reporting company” under applicable federal securities laws and will be subject to reduced public company reporting requirements
for so long as we remain a smaller reporting company. See the section titled “Prospectus Summary—Implications of Being a Smaller Reporting Company.”

Investing in these securities involves a high degree of risk. You should review carefully the risks and uncertainties described under the heading “ Risk
Factors ” on page 4 of this prospectus and any similar section contained in the applicable prospectus supplement and in any free writing prospectuses we have authorized for use in connection with a specific offering, and under similar headings
in the other documents that are incorporated by reference into this prospectus.
This prospectus may not be used to sell our securities unless
accompanied by a prospectus supplement.
None of the Securities and Exchange Commission, any state securities commission, the U.K. Financial Conduct
Authority, nor any other foreign securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus is      , 2026.

TABLE OF CONTENTS

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ABOUT THIS PROSPECTUS
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TRADEMARKS
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PROSPECTUS SUMMARY
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RISK FACTORS
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SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS
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USE OF PROCEEDS
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DESCRIPTION OF SHARE CAPITAL AND ARTICLES OF ASSOCIATION
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DESCRIPTION OF AMERICAN DEPOSITARY SHARES
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MATERIAL TAX CONSIDERATIONS
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LEGAL MATTERS
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EXPERTS
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SERVICE OF PROCESS AND ENFORCEMENT OF LIABILITIES
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WHERE YOU CAN FIND ADDITIONAL INFORMATION
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INCORPORATION BY REFERENCE
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ABOUT THIS PROSPECTUS

This prospectus is part of a registration statement on Form S-3 that we filed with the U.S. Securities and Exchange
Commission, or the SEC, utilizing a “shelf” registration process under the Securities Act of 1933, as amended, or the Securities Act. Under this shelf registration statement, we may, from time to time, offer and sell in one or more
offerings, up to a total dollar amount of $300,000,000 of ordinary shares (including ordinary shares represented by ADSs). Registration of the securities covered by this prospectus does not mean that these securities will necessarily be offered or
sold.
This prospectus provides you with a general description of the securities we may offer. Each time we offer securities under this prospectus, we
will provide a prospectus supplement that will contain more specific information about the terms of that offering. We may also authorize one or more free writing prospectuses to be provided to you that may contain material information relating to
these offerings. The prospectus supplement and any related free writing prospectus that we may authorize to be provided to you may also add, update or change any of the information contained in this prospectus or in the documents that we have
incorporated by reference into this prospectus. We urge you to carefully read this prospectus, any applicable prospectus supplement and any related free writing prospectuses we have authorized for use in connection with a specific offering, together
with the information incorporated herein by reference as described under the heading “Incorporation By Reference,” before investing in any of the securities being offered.

THIS PROSPECTUS MAY NOT BE USED TO CONSUMMATE A SALE OF SECURITIES UNLESS IT IS ACCOMPANIED BY A PROSPECTUS SUPPLEMENT. Neither we, nor any agent,
underwriter or dealer has authorized any person to give any information or to make any representation other than those contained or incorporated by reference in this prospectus, any applicable prospectus supplement or any related free writing
prospectus prepared by or on behalf of us or to which we have referred you. “Incorporated by reference” means that we can disclose important information to you by referring you to another document filed separately with the SEC. This
prospectus, any applicable supplement to this prospectus or any related free writing prospectus do not constitute an offer to sell or the solicitation of an offer to buy any securities other than the registered securities to which they relate, nor
do this prospectus, any applicable supplement to this prospectus or any related free writing prospectus constitute an offer to sell or the solicitation of an offer to buy securities in any jurisdiction to any person to whom it is unlawful to make
such offer or solicitation in such jurisdiction.
You should not assume that the information contained in this prospectus, any applicable prospectus
supplement or any related free writing prospectus is accurate on any date subsequent to the date set forth on the front of the document or that any information we have incorporated by reference is correct on any date subsequent to the date of the
document incorporated by reference, even though this prospectus, any applicable prospectus supplement or any related free writing prospectus is delivered, or securities are sold, on a later date.

This prospectus and the information incorporated herein by reference contains summaries of certain provisions contained in some of the documents described
herein, but reference is made to the actual documents for complete information. All of the summaries are qualified in their entirety by the actual documents. Copies of some of the documents referred to herein have been filed, will be filed or will
be incorporated by reference as exhibits to the registration statement of which this prospectus is a part, and you may obtain copies of those documents as described below under the heading “Where You Can Find Additional Information.”

Unless otherwise indicated or the context otherwise requires, all references in this prospectus to the terms “Silence Therapeutics,”
“Silence Therapeutics plc,” “the Company,” “we,” “us” and “our” refer to Silence Therapeutics plc together with its subsidiaries.

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For investors outside the United States: We have not done anything that would permit the offering or
possession or distribution of this prospectus in any jurisdiction where action for that purpose is required, other than in the United States. Persons outside the United States who come into possession of this prospectus must inform themselves about,
and observe any restrictions relating to, the offering of the securities described herein and the distribution of this prospectus outside the United States.

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TRADEMARKS

This prospectus includes trademarks, tradenames and service marks, certain of which belong to us and others that are the property of other organizations.
Solely for convenience, trademarks, tradenames and service marks referred to in this prospectus appear without the ® , ™ and SM
symbols, but the absence of those symbols is not intended to indicate, in any way, that we will not assert our rights or that the applicable owner will not assert its rights to these trademarks, tradenames and service marks to the fullest extent
under applicable law. We do not intend our use or display of other parties’ trademarks, trade names or service marks to imply, and such use or display should not be construed to imply a relationship with, or endorsement or sponsorship of us
by, these other parties.

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PROSPECTUS SUMMARY

This summary does not contain all of the information that may be important to you in making your investment decision. In addition to this summary, you
should carefully read the entire prospectus, the applicable prospectus supplement and any related free writing prospectus, including the risks of investing in our ordinary shares and ADSs discussed under the heading “Risk Factors”
contained herein and in the applicable prospectus supplement and any related free writing prospectus, and under similar headings in the other documents that are incorporated by reference into this prospectus. You should also carefully read the
information incorporated by reference into this prospectus, including our financial statements, and the exhibits to the registration statement of which this prospectus is a part.

Overview
We are a biotechnology company focused on
discovering and developing novel molecules incorporating short interfering ribonucleic acid, or siRNA, to inhibit the expression of specific target genes thought to play a role in the pathology of diseases with significant unmet medical need. Our
siRNA molecules are designed to harness the body’s natural mechanism of RNAi by specifically binding to and degrading messenger RNA, or mRNA, molecules that encode specific targeted disease-associated proteins in a cell. By degrading the
message that encodes the disease-associated protein, the production of that protein is reduced and its level of activity is lowered. In the field of RNAi therapeutics, this reduction of disease-associated protein production and activity is referred
to as “gene silencing.” Our proprietary mRNAi GOLD ™ ( G alNAc Ol igonucleotide D iscovery) platform consists of siRNA product candidates designed to precisely
target and ‘silence’ specific disease-associated genes in the liver. Using our mRNAi GOLD ™ platform, we have generated siRNA product candidates targeting areas of unmet need
across rare and common diseases where treatments are limited or inadequate.
Our Pipeline

Our pipeline is centered around mRNAi GOLD ™ platform and consists of a diversified set of therapeutic
areas, including cardiovascular disease, hematology and rare diseases. Our current pipeline is represented in the diagram below.

Implications of Being a Smaller Reporting Company

We are a “smaller reporting company” as defined in the Securities Exchange Act of 1934, or Exchange Act. As a result, we may take advantage of
certain of the scaled disclosures available to smaller reporting companies. As a

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smaller reporting company with annual revenues of less than $100 million and a non-accelerated filer, we are also not required to provide an
attestation report on internal control over financial reporting issued by our independent registered public accounting firm. We will remain a smaller reporting company until the fiscal year following the determination that the market value of our
shares held by non-affiliates is more than $250 million measured on the last business day of our second fiscal quarter, or our annual revenues are less than $100 million during the most recently
completed fiscal year and the market value of our shares held by non-affiliates is more than $700 million measured on the last business day of our second fiscal quarter.

Corporate History and Information
We were incorporated
as a public limited company under the laws of England and Wales on November 18, 1994, under the name Stanford Rook Holdings plc with company number 2992058. In July 2005, we acquired Atugen AG, a company specializing in siRNA. On April 26,
2007, we changed our name to Silence Therapeutics plc. Our principal executive offices are located at 12 Hammersmith Grove, London W6 7AP, United Kingdom and our telephone number is +44 20-3457-6900. Our
registered office address is 27 Eastcastle Street, London, W1W 8DH, United Kingdom. Our agent for service of process in the United States is Silence Therapeutics Inc., 221 River Street, 9th Floor, Hoboken, New Jersey 07030.

Our website address is www.silence-therapeutics.com. Information contained on, or that can be accessed through, our website is not incorporated by reference
into this prospectus, and you should not consider information on our website to be part of this prospectus.
The Securities We May Offer

Under this prospectus, we may offer ordinary shares or ADSs representing our ordinary shares from time to time at prices and on terms to be determined by
market conditions at the time of the offering. This prospectus provides you with a general description of the securities we may offer. Each time we offer a type or series of securities under this prospectus, we will provide a prospectus supplement
that will describe the specific amounts, prices and other important terms of the securities, including, to the extent applicable:

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designation or classification;
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aggregate principal amount or aggregate offering price;
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voting or other rights, if any; and
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conversion or exercise prices, if any.
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The prospectus supplement, and any related free writing prospectus that we may authorize to be provided to you, also may add, update or change information
contained in this prospectus or in documents we have incorporated by reference into this prospectus. However, no prospectus supplement or free writing prospectus will fundamentally change the terms that are set forth in this prospectus or offer a
security that is not registered and described in this prospectus at the time of the effectiveness of the registration statement of which this prospectus is a part.

We may sell the securities directly to investors or to or through agents, underwriters or dealers. We, and our agents or underwriters, reserve the right to
accept or reject all or part of any proposed purchase of securities. If we offer securities through agents or underwriters, we will include in the applicable prospectus supplement:

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the names of those agents or underwriters;
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applicable fees, discounts and commissions to be paid to them;
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details regarding over-allotment options, if any; and
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the net proceeds to us.
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This prospectus may not be used to consummate a sale of any securities unless it is accompanied by a prospectus supplement.

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RISK FACTORS

Investing in our securities involves a high degree of risk. You should carefully review the risks and uncertainties set forth below as well as those described
under the heading “Risk Factors” contained in the applicable prospectus supplement and any related free writing prospectus, and in our Annual Report on Form 10-K for the year ended
December 31, 2025, as updated by our subsequent SEC filings, which are incorporated by reference into this prospectus, before deciding whether to purchase any of the securities being registered pursuant to the registration statement of which
this prospectus is a part. Each of the risk factors could adversely affect our business, results of operations, financial condition and cash flows, as well as adversely affect the value of an investment in our securities, and the occurrence of any
of these risks might cause you to lose all or part of your investment. Additional risks not presently known to us or that we currently believe are immaterial may also significantly impair our business operations.

Risks Related to Our Securities
If we are a
passive foreign investment company, there could be adverse U.S. federal income tax consequences to U.S. Holders.
Under the Internal Revenue Code
of 1986, as amended, or the Code, we will be a passive foreign investment company, or PFIC, for any taxable year in which (i) 75% or more of our gross income consists of passive income, or (ii) 50% or more of the average quarterly value of our
assets consists of assets that produce, or are held for the production of, passive income (including cash). For purposes of these tests, passive income includes dividends, interest, gains from the sale or exchange of investment property and certain
rents and royalties. In addition, for purposes of the above calculations, a non-U.S. corporation that directly or indirectly owns at least 25% by value of the shares of another corporation is treated as if it
held its proportionate share of the assets and received directly its proportionate share of the income of such other corporation.
Although we believed
that we may have been a PFIC for our taxable year ended December 31, 2025, we have performed further tax analysis and currently believe that, based on the nature of our activities and the composition of our income and assets, we were not
classified as a PFIC for our taxable year ended December 31, 2025. However, no assurances regarding our PFIC status can be provided for any past, current or future taxable year. The determination of whether we are a PFIC is a fact-intensive
determination made on an annual basis and the applicable law is subject to varying interpretation. In particular, the characterization of our assets as active or passive may depend in part on our current and intended future business plans, which are
subject to change. In addition, the total value of our assets for PFIC testing purposes may be determined in part by reference to the market price of our ordinary shares or ADSs from time to time, which may fluctuate considerably. Under the income
test, our status as a PFIC depends on the composition of our income which will depend on a variety of factors that are subject to uncertainty, including the characterization of certain intercompany payments and payments from tax authorities,
transactions we enter into in the future and our corporate structure. Even if we determine that we are not a PFIC for a taxable year, there can be no assurance that the IRS would not successfully challenge our position. Accordingly, our U.S. counsel
expresses no opinion with respect to our PFIC status for any prior, current or future taxable year.
For each year we are treated as a PFIC with respect
to U.S. Holders (as defined below under “Material Tax Considerations – Material U.S. Federal Income Tax Considerations for U.S. Holders”), U.S. Holders will be subject to adverse U.S. federal income tax consequences, such as
ineligibility for any preferential tax rates for individuals on capital gains or on actual or deemed dividends, interest charges on certain taxes treated as deferred, and additional reporting requirements under U.S. federal income tax laws and
regulations, unless such U.S. Holder makes a “qualified electing fund” election, or QEF Election, with respect to all taxable years during such U.S. Holder’s holding period in which we are a PFIC, or our ordinary shares constitute
“marketable stock” and such U.S. Holder makes a mark-to-market election. However, a U.S. Holder can only make a QEF Election with respect to ordinary shares
or ADSs in a PFIC if such company agrees to furnish such U.S. Holder with certain tax information annually. As we do not believe that we were a PFIC for the taxable year ended

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December 31, 2025, we do not currently expect to provide such information for such taxable year and may not provide such information in future taxable years, whether or not we are classified
as a PFIC.
Each U.S. Holder should consult its own tax advisors with respect to the potential adverse U.S. tax consequences to it if we are or were to
become a PFIC and any elections that may be available to such U.S. Holder that relate to our status as a PFIC. For further discussion of the PFIC rules and the adverse U.S. federal income tax consequences in the event we are classified as a PFIC, as
well as certain elections that may be available to U.S. Holders, see the discussion below under “Material Tax Considerations – Material U.S. Federal Income Tax Considerations for U.S. Holders – Passive Foreign Investment Company
Rules.”

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SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus, the documents incorporated by reference and any free writing prospectus prepared by or on behalf of us or to which we have referred you
contain “forward-looking statements” within the meaning of Section 27A of the Securities Act and Section 21E of the Exchange Act, that involve substantial risks and uncertainties. In some cases, you can identify forward-looking
statements by terminology such as “anticipate,” “believe,” “could,” “estimate,” “expects,” “intend,” “may,” “plan,” “potential,”
“predict,” “project,” “should,” “will,” “would” or the negative or plural of those terms, and similar expressions intended to identify statements about the future, although not all
forward-looking statements contain these words. These statements involve known and unknown risks, uncertainties and other factors that may cause our actual results, levels of activity, performance or achievements to be materially different from the
information expressed or implied by these forward-looking statements. The forward-looking statements contained in this prospectus and the documents incorporated by reference into this prospectus are based upon information available to us as of the
date of this prospectus and, while we believe such information forms a reasonable basis for such statements, such information may be limited or incomplete, and our statements should not be read to indicate that we have conducted an exhaustive
inquiry into, or review of, all potentially available relevant information.
Forward-looking statements include, but are not limited to, statements
regarding:

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the development of our product candidates, including statements regarding the timing of initiation, completion
and the outcome of preclinical studies or clinical trials and related preparatory work, the period during which the results of the trials will become available and our research and development programs;
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our ability to obtain and maintain regulatory approval of our product candidates in the indications for which we
plan to develop them, and any related restrictions, limitations or warnings in the label of an approved drug or therapy;
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our plans to collaborate, or statements regarding the ongoing collaborations, with third parties;

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our plans to research, develop, manufacture and commercialize our product candidates;
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the timing of our regulatory filings for our product candidates;
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the size and growth potential of the markets for our product candidates;
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our ability to raise additional capital;
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our commercialization, marketing and manufacturing capabilities and strategy;
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our expectations regarding our ability to obtain and maintain intellectual property protection;

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our ability to attract and retain qualified employees and key personnel;
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our ability to contract with third-party suppliers and manufacturers and their ability to perform adequately;

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our estimates regarding future revenue, expenses and needs for additional financing;
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our ability to retain our status as a smaller reporting company;
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our expectations regarding our cash runway and our expected use of cash, cash equivalents and short-term investments;
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regulatory developments in the United States, United Kingdom, European Union, or EU, and other jurisdictions; and

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any other factors which may impact our financial results or future trading prices of the ADSs.

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You should refer to the important factors in the cautionary statements included in this prospectus and in
the other documents incorporated herein, for a discussion of important factors that may cause our actual results to differ materially from those expressed or implied by our forward-looking statements. As a result of these factors, we cannot assure
you that the forward-looking statements in this prospectus will prove to be accurate. Furthermore, if our forward-looking statements prove to be inaccurate, the inaccuracy may be material. In light of the significant uncertainties in these
forward-looking statements, you should not regard these statements as a representation or warranty by us or any other person that we will achieve our objectives and plans in any specified time frame, or at all. We undertake no obligation to publicly
update any forward-looking statements, whether as a result of new information, future events or otherwise, except as required by law.
You should read
this prospectus, any applicable prospectus supplement, any free writing prospectuses that we may authorize for use in connection with an offering and the documents that we reference in this prospectus and have filed as exhibits to the registration
statement of which this prospectus is a part completely and with the understanding that our actual future results may be materially different from what we expect.

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USE OF PROCEEDS

Unless otherwise indicated in the applicable prospectus supplement or in any free writing prospectus that we may have authorized to be provided to you in
connection with a specific offering, we intend to use any net proceeds from the sale of securities under this prospectus to fund activities relating to the continued clinical development of our product candidates and for other general corporate
purposes, including, but not limited to, working capital, capital expenditures, investments, acquisitions, should we choose to pursue any, and collaborations. We have not determined the amounts we plan to spend on any of the areas listed above or
the timing of these expenditures. As a result, our management will have broad discretion to allocate the net proceeds, if any, we receive in connection with securities offered pursuant to this prospectus for any purpose. Pending application of the
net proceeds as described above, we may initially invest the net proceeds in short-term, investment-grade and interest-bearing securities.

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PLAN OF DISTRIBUTION

We may offer securities under this prospectus from time to time pursuant to underwritten public offerings, negotiated transactions, block trades or a
combination of these methods. We may sell the securities (1) through underwriters or dealers, (2) through agents or (3) directly to one or more purchasers, or (4) through a combination of such methods. We may distribute the
securities from time to time in one or more transactions at:

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a fixed price or prices, which may be changed from time to time;
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market prices prevailing at the time of sale;
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prices related to the prevailing market prices; or
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negotiated prices.
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Each time that we sell securities covered by this prospectus, we will provide a prospectus supplement or supplements that will describe the method of
distribution and set forth the terms and conditions of the offering of such securities, including the offering price of the securities and the proceeds to us, if applicable.

We may directly solicit offers to purchase the securities being offered by this prospectus. We may also designate agents to solicit offers to purchase the
securities from time to time, and may enter into arrangements for “at-the-market,” equity line or similar transactions. We will name in a prospectus
supplement any underwriter or agent involved in the offer or sale of the securities.
If we utilize a dealer in the sale of the securities being offered
by this prospectus, we or the selling shareholders will sell the securities to the dealer, as principal. The dealer may then resell the securities to the public at varying prices to be determined by the dealer at the time of resale.

If we utilize an underwriter in the sale of the securities being offered by this prospectus, we will execute an underwriting agreement with the underwriter at
the time of sale, and we will provide the name of any underwriter in the prospectus supplement which the underwriter will use to make resales of the securities to the public. In connection with the sale of the securities, we or the purchasers of the
securities for whom the underwriter may act as agent, may compensate the underwriter in the form of underwriting discounts or commissions. The underwriter may sell the securities to or through dealers, and the underwriter may compensate those
dealers in the form of discounts, concessions or commissions.
With respect to underwritten public offerings, negotiated transactions and block trades, we
will provide in the applicable prospectus supplement information regarding any compensation we pay to underwriters, dealers or agents in connection with the offering of the securities, and any discounts, concessions or commissions allowed by
underwriters to participating dealers. Underwriters, dealers and agents participating in the distribution of the securities may be deemed to be underwriters within the meaning of the Securities Act, and any discounts and commissions received by them
and any profit realized by them on resale of the securities may be deemed to be underwriting discounts and commissions. We may enter into agreements to indemnify underwriters, dealers and agents against civil liabilities, including liabilities under
the Securities Act, or to contribute to payments they may be required to make in respect thereof.
If so indicated in the applicable prospectus
supplement, we may authorize underwriters, dealers or other persons acting as our agents to solicit offers by certain institutions to purchase securities from us pursuant to delayed delivery contracts providing for payment and delivery on the date
stated in each applicable prospectus supplement. Each contract will be for an amount not less than, and the aggregate amount of securities sold pursuant to such contracts shall not be less nor more than, the respective amounts stated in each
applicable

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prospectus supplement. Institutions with whom the contracts, when authorized, may be made include commercial and savings banks, insurance companies, pension funds, investment companies,
educational and charitable institutions and other institutions, but shall in all cases be subject to our approval. Delayed delivery contracts will not be subject to any conditions except that:

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the purchase by an institution of the securities covered under that contract shall not at the time of delivery be
prohibited under the laws of the jurisdiction to which that institution is subject; and
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if the securities are also being sold to underwriters acting as principals for their own account, the
underwriters shall have purchased such securities not sold for delayed delivery. The underwriters and other persons acting as our agents will not have any responsibility in respect of the validity or performance of delayed delivery contracts.

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One or more firms, referred to as “remarketing firms,” may also offer or sell the securities, if a prospectus supplement so
indicates, in connection with a remarketing arrangement upon their purchase. Remarketing firms will act as principals for their own accounts or as our agents. These remarketing firms will offer or sell the securities in accordance with the terms of
the securities. Each prospectus supplement will identify and describe any remarketing firm and the terms of its agreement, if any, with us and will describe the remarketing firm’s compensation. Remarketing firms may be deemed to be
underwriters in connection with the securities they remarket. Remarketing firms may be entitled under agreements that may be entered into with us to indemnification by us against certain civil liabilities, including liabilities under the Securities
Act, and may be customers of, engage in transactions with or perform services for us in the ordinary course of business.
Certain underwriters may use
this prospectus and any accompanying prospectus supplement for offers and sales related to market-making transactions in the securities. These underwriters may act as principal or agent in these transactions, and the sales will be made at prices
related to prevailing market prices at the time of sale. Any underwriters involved in the sale of the securities may qualify as “underwriters” within the meaning of Section 2(a)(11) of the Securities Act. In addition, the
underwriters’ commissions, discounts or concessions may qualify as underwriters’ compensation under the Securities Act and the rules of the Financial Industry Regulatory Authority, Inc., or FINRA.

ADSs representing our ordinary shares sold pursuant to the registration statement of which this prospectus is a part will be authorized for listing and
trading on The Nasdaq Global Select Market. The applicable prospectus supplement will contain information, where applicable, as to any other listing, if any, on The Nasdaq Global Select Market or any securities market or other securities exchange of
the securities covered by the prospectus supplement. Underwriters may make a market in the ADSs, but will not be obligated to do so and may discontinue any market making at any time without notice. We can make no assurance as to the liquidity of or
the existence, development or maintenance of trading markets for any of the securities.
In order to facilitate the offering of the securities, certain
persons participating in the offering may engage in transactions that stabilize, maintain or otherwise affect the price of the securities. This may include over-allotments or short sales of the securities, which involve the sale by persons
participating in the offering of more securities than we sold to them. In these circumstances, these persons would cover such over-allotments or short positions by making purchases in the open market or by exercising their over-allotment option. In
addition, these persons may stabilize or maintain the price of the securities by bidding for or purchasing the applicable security in the open market or by imposing penalty bids, whereby selling concessions allowed to dealers participating in the
offering may be reclaimed if the securities sold by them are repurchased in connection with stabilization transactions. The effect of these transactions may be to stabilize or maintain the market price of the securities at a level above that which
might otherwise prevail in the open market. These transactions may be discontinued at any time.
The underwriters, dealers and agents may engage in other
transactions with us, or perform other services for us, in the ordinary course of their business.

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DESCRIPTION OF SHARE CAPITAL AND ARTICLES OF ASSOCIATION

Set forth below is a summary of certain information concerning our share capital as well as a description of certain provisions of our articles of
association and relevant provisions of the U.K. Companies Act 2006, or the Companies Act. The summary below contains only material information concerning our share capital and corporate status and does not purport to be complete and is qualified in
its entirety by reference to the full version of our articles of association, which are incorporated by reference herein. Further, please note that holders of the American Depositary Shares, or ADSs, representing our ordinary shares will not be
treated as one of our shareholders and will not have any shareholder rights.
General

We were incorporated as a public limited company under the laws of England and Wales on November 18, 1994 under the name Stanford Rook Holdings plc with
company number 2992058. In July 2005, we acquired Atugen AG, a company specializing in siRNA. On April 26, 2007, we changed our name to Silence Therapeutics plc. Our principal executive offices are located at 12 Hammersmith Grove, London W6
7AP, United Kingdom and our telephone number is +44 20-3457-6900. Our registered office address is 27 Eastcastle Street, London, W1W 8DH, United Kingdom.

Our ADSs are listed on The Nasdaq Global Market under the trading symbol “SLN.” Our ordinary shares are registered under the Exchange Act, not for
trading, but only in connection with the listing of the ADSs on The Nasdaq Global Market.
The principal legislation under which we operate and under
which our ordinary shares are issued is the Companies Act. As of April 30, 2026, the issued and outstanding share capital of Silence Therapeutics plc was 141,703,840 ordinary shares issued and outstanding, with a nominal value of £0.05
per ordinary share. Each issued ordinary share is fully paid.
Ordinary Shares

In accordance with our articles of association, the following summarizes the rights of holders of our ordinary shares:

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each holder of our ordinary shares is entitled to one vote per ordinary share on all matters to be voted on by
shareholders generally;
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the holders of the ordinary shares shall be entitled to receive notice of, attend, speak and vote at our general
meetings; and
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holders of our ordinary shares are entitled to receive such dividends as are recommended by our directors and
declared by our shareholders.
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See also “—Articles of Association” below.

Options
As of March 31, 2026, there were options to
purchase 23,196,120 ordinary shares (7,732,040 ADSs) outstanding with a weighted average exercise price of $4.19 per ordinary share. The options generally lapse after 10 years from the date of the grant.

Register of Members
We are required by the Companies Act
to keep a register of our shareholders. Under the laws of England and Wales, the ordinary shares are deemed to be issued when the name of the shareholder is entered in our share register. The share register, therefore, is prima facie evidence of the
identity of our shareholders, and the shares

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that they hold. The share register generally provides limited, or no, information regarding the ultimate beneficial owners of our ordinary shares. Our share register is maintained by our
registrar, MUFG Corporate Markets.
Holders of the ADSs will not be treated as one of our shareholders and their names will therefore not be entered in
our share register. The depositary, the custodian or their nominees will be the holder of the ordinary shares underlying the ADSs. Holders of the ADSs have a right to receive the ordinary shares underlying their ADSs upon surrender and cancellation
of the ADSs. For discussion on the ADSs and ADS holder rights see “Description of American Depositary Shares”.
Under the Companies Act, we
must enter an allotment of shares in our share register as soon as practicable and in any event within two months of the allotment. We also are required by the Companies Act to register a transfer of shares (or give the transferee notice of and
reasons for refusal) as soon as practicable and in any event within two months of receiving notice of the transfer.
We, any of our shareholders, or any
other affected person may apply to the court for rectification of the share register if:

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the name of any person, without sufficient cause, is wrongly entered in or omitted from our register of
shareholders; or
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there is a default or unnecessary delay in entering on the register the fact of any person having ceased to be a
shareholder or on which we have a lien, provided that such refusal does not prevent dealings in the shares taking place on an open and proper basis.
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Preemptive Rights
The laws of England and Wales
generally provide shareholders with preemptive rights when new shares are issued for cash; however, it is possible for the articles of association, or shareholders at a general meeting representing at least 75% of our ordinary shares present (in
person or by proxy) and voting at that general meeting, to disapply these preemptive rights. Such a disapplication of preemptive rights may be for a maximum period of up to five years from the date of adoption of the articles of association, if the
disapplication is contained in the articles of association, or from the date of the shareholder resolution, if the disapplication is by shareholder resolution. In either case, this disapplication would need to be renewed by our shareholders upon its
expiration (i.e., at least every five years) to be effective.
On April 27, 2023, our shareholders approved the disapplication of preemptive rights
for a period of five years from the date of approval in relation to the equity securities (within the meaning of the Companies Act) authorized to be allotted pursuant to such resolution, which disapplication will need to be renewed upon expiration
(i.e., at least every five years) to remain effective, but may be sought more frequently for additional five-year terms (or any shorter period). The disapplication of preemptive rights is limited to the allotment of equity securities (within the
meaning of the Companies Act) up to a maximum aggregate nominal amount of £5,402,633.25.
Key Provisions of Our Articles of Association

The following is a summary of certain key provisions of our articles of association. Please note that this is only a summary and is not intended to be
exhaustive.
The articles of association contain, among other things, provisions to the following effect:

Objects
The objects of the Company are
unrestricted.

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Shares and Rights Attaching to Them

Share Rights
Subject to any special rights attaching to
shares or class of shares already in issue, our shares may be issued with or have attached to them any preferred, deferred or other special rights or be subject to such restrictions, whether in regard to dividend, voting, return of capital or
otherwise, as we may by ordinary resolution of the shareholders determine or, in the absence of any such determination, as our board may determine.

Voting Rights
Subject to any rights or restrictions
attached to any shares from time to time, the voting rights attaching to our shares are as follows:

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on a show of hands, every shareholder present in person shall have one vote;
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on a show of hands, each proxy present in person has one vote for and one vote against a resolution if the proxy
has been duly appointed by more than one shareholder and the proxy has been instructed by one or more of those shareholders to vote for the resolution and by one or more other of those shareholders to vote against it;
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on a show of hands, each proxy present in person has one vote for and one vote against a resolution if the proxy
has been duly appointed by more than one shareholder entitled to vote on the resolution and either: (1) the proxy has been instructed by one or more of those shareholders to vote for the resolution and has been given any discretion by one or
more other of those shareholders to vote and the proxy exercises that discretion to vote against it; or (2) the proxy has been instructed by one or more of those shareholders to vote against the resolution and has been given any discretion by
one or more other of those shareholders to vote and the proxy exercises that discretion to vote for it;
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on a show of hands, each duly authorised corporate representative has one vote;
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on a poll every shareholder who is present in person or by proxy or by corporate representative shall have one
vote for each share of which he or she is the holder or in respect of which their appointment as proxy or corporate representative is made; and
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in the case of joint holders of a share, the vote of the senior holder who votes shall be accepted to the
exclusion of the votes of the other joint holders (and seniority shall be determined by the order in which the names stand in the register in respect of the share).
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At any general meeting a resolution put to the vote of the meeting shall be decided on a show of hands unless a
poll is (before or on the declaration of the result of the show of hands) demanded. Subject to the provisions of the Companies Act, as described in “Differences in Corporate Law—Voting Rights,” a poll may be demanded by:

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the chairman of the meeting;
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at least five shareholders present in person or by proxy and entitled to vote on the resolution;

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any shareholder(s) present in person or by proxy and representing in the aggregate not less than one-tenth of the total voting rights of all shareholders having the right to attend and vote at the meeting (excluding the shares held in treasury); or
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any shareholder(s) present in person or by proxy and holding shares conferring a right to vote on the resolution
at the meeting on which there have been paid up sums in the aggregate equal to not less than one-tenth of the total sums paid up on all shares conferring that right (excluding the shares held in treasury).

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A resolution put to the vote at a general meeting held partly by means of electronic facility or facilities shall, unless the chairman
of the meeting determines that it shall be decided on a show of hands, be decided on a poll.

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Restrictions on Voting

No shareholder shall, unless the directors otherwise determine, be entitled to vote, either in person or by proxy, at any general meeting or at any separate
class meeting in respect of any share held by such shareholder unless all calls or other sums payable by such shareholder in respect of that share have been paid.

The board of directors, or the board, may from time to time make calls upon the shareholders in respect of any money unpaid on their shares and each
shareholder shall (subject to us serving on such shareholder at least 14 days’ notice specifying the time or times and place of payment) pay at the time or times so specified the amount called on such holder’s shares.

Dividends
We may, subject to the provisions of the
Companies Act and the articles of association, by ordinary resolution of shareholders declare dividends out of profits available for distribution in accordance with the respective rights of shareholders but no such dividend shall exceed the amount
recommended by the directors. The directors may from time to time pay shareholders such interim dividends as they think fit and may also pay the fixed dividends payable on any shares of the company half-yearly or otherwise on fixed dates. If the
directors act in good faith, they shall not incur any liability to the holders of shares conferring preferred rights for any loss they may suffer in consequence of the payment of an interim dividend on any shares having non-preferred or deferred rights.
Subject to any special rights attaching to or the terms of issue of any share, all
dividends shall be declared and paid according to the amounts paid up on the shares and shall be apportioned and paid proportionately according to the amounts paid up on the shares during any part or parts of the period in respect of which the
dividend is paid.
Subject to any rights attaching to or the terms of issue of any shares, no dividend or other monies payable by us on or in respect of
any share shall bear interest against us. Any dividend unclaimed after a period of 12 years from the date such dividend became due for payment shall be forfeited and shall revert to us.

Dividends may be declared or paid in any currency or currencies and the board may decide the rate of exchange for any currency conversions that may be
required, and how any costs involved are to be met.
Any general meeting declaring a dividend may by ordinary resolution of shareholders, upon the
recommendation of the board, direct payment or satisfaction of such dividend wholly or in part by the distribution of specific assets other than cash, and in particular of paid up shares or debentures of any other company. The directors may, if
authorized by ordinary resolution of shareholders, offer any holders of ordinary shares the right to elect to receive in lieu of a dividend an allotment of ordinary shares credited as fully paid up, subject to such exclusions and other arrangements
as the board may deem necessary or expedient to deal with legal or practical problems in respect of overseas shareholders or in respect of shares represented by depositary receipts.

Change of Control
There is no specific provision in the
articles of association that would have the effect of delaying, deferring or preventing a change of control.
Distributions on Winding Up

On a winding up, the liquidator may, with the sanction of a special resolution of shareholders and any other sanctions required by law, divide amongst the
shareholders (excluding the company itself to the extent it is a shareholder by virtue only of its holding of shares as treasury shares) in specie or in kind the whole or any part of our assets (whether they shall consist of property of the same
kind or not) and may set such values as he or she

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deems fair upon any property to be divided and may determine how such division shall be carried out as between the shareholders or different classes of shareholder. The liquidator may, with the
sanction of a special resolution of the shareholders and any other sanctions required by law, vest the whole or any part of such assets in trustees upon such trusts for the benefit of the shareholders as the liquidator shall think fit, but no
shareholder shall be compelled to accept any shares or other assets upon which there is any liability.
Variation of Rights

All or any of the rights and restrictions attached to any class of shares issued may be abrogated or varied with the consent in writing of the holders of at
least three-quarters in nominal value of the issued shares of that class (excluding any shares held as treasury shares) or by special resolution passed at a separate general meeting of the holders of such class of shares, subject to the Companies
Act and the terms of their issue. The Companies Act provides a right to object to the variation of the share capital by the shareholders who did not vote in favor of the variation. Should an aggregate of 15% of the shareholders of the issued shares
in question apply to the court to have the variation cancelled, the variation shall have no effect unless and until it is confirmed by the court.

Alteration to Share Capital
We may, by ordinary
resolution of shareholders, consolidate all or any of our share capital into shares of larger nominal amount than our existing shares, or sub-divide our shares or any of them into shares of a smaller amount.
We may, by special resolution of shareholders, confirmed by the court, reduce our share capital, any capital redemption reserve or any share premium account in any manner authorized by the Companies Act. We may redeem or purchase all or any of our
shares as described in “Other English Law Considerations—Purchase of Own Shares.”
Preemption Rights

Subject to the Companies Act and to any rights attached to existing shares, any share may be issued with or have attached to it such rights and restrictions as
we may by ordinary resolution determine, or if no ordinary resolution has been passed or so far as the resolution does not make specific provision, as our board of directors may determine (including shares which are to be redeemed, or are liable to
be redeemed at our option or the holder of such shares).
In accordance with the Companies Act, the board of directors may be generally and
unconditionally authorized to exercise for each prescribed period of up to five years all the powers of the Company to allot shares or grant rights to subscribe for or to convert any security into shares up to an aggregate nominal amount equal to
the amount stated in the relevant ordinary resolution authorizing such allotment.
On April 27, 2023, our shareholders approved a resolution
authorizing the board of directors pursuant to Section 551 of the Companies Act to allot new shares or to grant rights to subscribe for or to convert any security into shares in the company up to a maximum aggregate nominal amount of
£5,402,633.25. This authority runs for five years and will expire on April 26, 2028.
On April 27, 2023, our shareholders approved the
disapplication of preemptive rights for a period of five years from the date of approval in relation to the equity securities (within the meaning of the Companies Act) authorized to be allotted pursuant to such resolution, which disapplication will
need to be renewed upon expiration (i.e., at least every five years) to remain effective, but may be sought more frequently for additional five-year terms (or any shorter period). The disapplication of preemptive rights is limited to the allotment
of equity securities (within the meaning of the Companies Act) up to a maximum aggregate nominal amount of £5,402,633.25.

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Transfer of Shares

Any certificated shareholder may transfer all or any of his, her or its shares by an instrument of transfer in any usual or common form or in any other manner
which is permitted by the Companies Act and approved by the board. Any written instrument of transfer shall be signed by or on behalf of the transferor and in the case of a partly paid share, the transferee.

The board may decline to register any transfer of any share:

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which is not a fully paid share, provided that, where any such shares or securities are listed on any stock
exchange, such discretion may not be exercised in a way in which the U.K. Financial Conduct Authority, the London Stock Exchange or any other relevant regulator or stock exchange regards as preventing dealing in shares or other securities from
taking place on an open and proper basis;
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unless any written instrument of transfer, duly stamped (if required), is deposited with us at our registered
office or such other place as the board may from time to time determine, accompanied by the certificate for the shares to which it relates;
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unless there is provided such evidence as the board may reasonably require to show the right of the transferor to
make the transfer and if the instrument of transfer is executed by some other person on his, her or its behalf, the authority of that person to do so;
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where the transfer is in respect of more than one class of share; and
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in the case of a transfer to joint holders, the number of joint holders to whom the share is to be transferred
exceeds four.
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If the board declines to register a transfer of a certificated share it shall, as soon as practicable and in any event
within two months after the date on which the transfer is lodged, send to the transferee notice of the refusal, together with reasons for the refusal.

Shareholder Meetings
Annual General Meetings

In accordance with the Companies Act, we are required in each year to hold an annual general meeting in addition to any other general meetings in
that year and to specify the meeting as such in the notice convening it. The annual general meeting shall be convened at such time and place and with such additional means of attendance and participation (including at such other place(s) and/or by
means of an electronic facility or facilities) as the board sees fit, subject to the requirements of the Companies Act, as described in “Differences in Corporate Law—Annual General Meeting” and “Differences in Corporate
Law—Notice of General Meetings.”
Notice of General Meetings

The arrangements for the calling of general meetings are described in “Differences in Corporate Law—Notice of General Meetings.”

Quorum of General Meetings
No business shall be
transacted at any general meeting unless a quorum is present. A quorum shall be present if both: (a) two qualifying persons are present at a general meeting unless each is a qualifying person only because (i) he is authorized to act as the
representative of a corporation in relation to the general meeting, and they are representatives of the same corporation or (ii) he is appointed as proxy of a member in relation to the general meeting, and they are proxies of the same member;
and (b) those qualifying persons present together hold (or are the representative or proxy of members in relation to the general meeting holding) at least one-third (33 1/3 percent) of the number of the
issued shares (excluding any shares held as treasury shares) entitled to vote on the business to be transacted at the general meeting.

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A “qualifying person” is an individual who is a member, a person authorized to act as the
representative of a member (being a corporation) in relation to the meeting or a person appointed as proxy of a member in relation to the general meeting. Where a qualifying person is present as proxy of a member in relation to the general meeting,
only the shares in respect of which the proxy is authorized to exercise voting rights will be treated as held for the purposes of determining whether a quorum is present.

Class Meetings
The provisions in our
articles of association relating to general meetings apply to every separate general meeting of the holders of a class of shares except that:

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the quorum for such class meeting shall be two holders present holding or representing by proxy at least one-third (33 1/3 percent) in number of the issued shares of the class in question (excluding any shares of that class held as treasury shares); and
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at the class meeting, a holder of shares of the class present in person or by proxy may demand a poll and shall
on a poll be entitled to one vote for every share of the class held by him or her.
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Directors

Number of Directors
Unless and until otherwise
determined by an ordinary resolution of shareholders, we may not have less than two directors on the board of directors but are not subject to any maximum number of directors.

Appointment of Directors
Subject to the
provisions of our articles of association, we may, by ordinary resolution of the shareholders, elect any person who is willing to act to be a director, either to fill a casual vacancy or as an addition to the existing board. However, any person that
is not a director retiring from the existing board must be recommended by the board of directors, or be proposed by a shareholder not less than seven and not more than 42 days before the date appointed for the meeting in order to be eligible for
election.
Without prejudice to the power to appoint any person to be a director by shareholder resolution, the board has power to appoint any person to
be a director, either to fill a casual vacancy or as an addition to the existing board but so that the total number of directors does not exceed any maximum number fixed by or in accordance with our articles of association.

Any director appointed by the board will hold office only until the following annual general meeting. Such a director is eligible for re-appointment at that meeting.
Rotation of Directors

At every annual general meeting, there shall retire from office any director who shall have been a director at each of the preceding two annual general
meetings and who was not appointed or re-appointed by us in general meeting at, or since, either such meeting. A retiring director shall be eligible for re-appointment.
A director retiring at a meeting shall, if he or she is not re-appointed at such meeting, retain office until the meeting appoints someone in his or her place, or if it does not do so, until the conclusion of
such meeting.
Directors’ Interests
The
directors may authorize, to the fullest extent permitted by law, any matter proposed to them which would otherwise result in a director infringing his or her duty to avoid a situation in which he or she has, or can have, a direct or indirect
interest that conflicts, or possibly may conflict, with our interests. A director shall not, save as otherwise agreed by him or her, be accountable to us for any benefit which he or she derives from any matter authorized by the directors and any
contract, transaction or arrangement relating thereto shall not be liable to be avoided on the grounds of any such benefit.

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Subject to the requirements under sections 175, 177 and 182 of the Companies Act, a director who is in any
way, whether directly or indirectly, interested in a proposed or existing transaction or arrangement with us shall declare the nature of his interest at a meeting of the directors.

A director shall not vote in respect of any contract, arrangement or transaction whatsoever in which he or she has an interest which is to his or her
knowledge a material interest otherwise than by virtue of interests in shares or debentures or other securities of or otherwise in or through our company. A director shall not be counted in the quorum at a meeting in relation to any resolution on
which he or she is debarred from voting.
A director shall be entitled to vote (and be counted in the quorum) in respect of any resolution concerning any
of the following matters:

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the giving of any guarantee, security or indemnity in respect of money lent or obligations incurred by him or her
or by any other person at the request of or for the benefit of our company or any of our subsidiary undertakings;
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the giving of any guarantee, security or indemnity in respect of a debt or obligation of our company or any of
our subsidiary undertakings for which he or she has assumed responsibility in whole or in part under a guarantee or indemnity or by the giving of security;
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any proposal concerning an offer of securities of or by our company or any of our subsidiary undertakings in
which offer he or she is or may be entitled to participate as a holder of securities or in the underwriting or sub-underwriting of which he or she is to participate;
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any contract, arrangement or transaction concerning any other body corporate in which he or she or any person
connected with him or her (within the meaning of sections 252 to 255 of the Companies Act) is interested, directly or indirectly and whether as an officer or shareholder or otherwise howsoever, provided that he or she and any persons so connected
with him or her do not to his or her knowledge hold an interest (within the meaning of sections 820 to 825 of the Companies Act) in one percent or more of any class of the equity share capital of such body corporate or of the voting rights available
to members of the relevant body corporate;
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any contract, arrangement or transaction for the benefit of employees of our company or any of our subsidiary
undertakings which does not accord to him or her any privilege or advantage not generally accorded to the employees to whom the scheme relates;
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any contract, arrangement or transaction concerning any insurance which our company is to purchase and/or
maintain for, or for the benefit of, any directors or persons including directors;
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the giving of an indemnity in relation to another director; and
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the provision of funds to any director to meet, or the doing of anything to enable a director to avoid incurring,
expenditure of the nature described in section 205(1) or 206 of the Companies Act.
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If a question arises at a meeting of the board or of
a committee of the board as to the right of a director to vote or be counted in the quorum, and such question is not resolved by his or her voluntarily agreeing to abstain from voting or not to be counted in the quorum, the question shall be
determined by the chairman and his or her ruling in relation to any director other than himself or herself shall be final and conclusive except in a case where the nature or extent of the interest of the director concerned has not been fairly
disclosed.
Directors’ Fees and Remuneration

Each of the directors shall be paid a fee in such sums as may from time to time be determined by the directors provided that the aggregate of all such fees so
paid to directors shall not exceed £500,000 per annum, or such higher amount as may from time to time be determined by ordinary resolution of shareholders.

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Each director may be paid all his or her reasonable traveling, hotel and other expenses properly incurred in
attending and returning from meetings of the directors or committees of the directors or general meetings of the company or separate meetings of the holders of any class of shares or debentures of the company or otherwise in connection with the
business of our company.
Any director who is appointed to any executive office or who serves on any committee or who devotes special attention to the
business of our company, or who otherwise performs services which in the opinion of the directors are outside the scope of the ordinary duties of a director, may be paid such extra remuneration by way of salary, percentage of profits or otherwise as
the directors may determine.
Borrowing Powers

The board may exercise all the powers to borrow money and to mortgage or charge our undertaking, property and assets (present or future) and uncalled capital
or any part thereof and to issue debentures, debenture stock and other securities, whether outright or as collateral security for any debt, liability or obligation of us or of any third party.

The board must restrict the borrowings of the Company and exercise all voting and other rights or powers of control exercisable by the Company in relation to
its subsidiaries so as to secure that the aggregate amount remaining outstanding of all monies borrowed by the Company and its subsidiaries shall not at any time, without the previous sanction of an ordinary resolution of the shareholders, exceed a
sum equal to five (5) times the aggregate of:

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the amount paid up on the issued share capital of the Company; and
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the total of the capital and revenue reserves of the Company and its subsidiaries (including any share premium
account, capital redemption reserve and credit balance on the profit and loss or income account) in each case, whether or not such amounts are available for distribution;
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all as shown in the latest audited consolidated balance sheet, subject to certain adjustments.

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Indemnity
Every director
or other officer of our group may be indemnified against all costs, charges, expenses, losses and liabilities sustained or incurred by him or her in connection with the actual or purported execution and/or discharge of his or her duties (including
those duties, powers and discretions in relation to any members of our group) including all costs, charges, expenses, losses and liabilities suffered or incurred in disputing, defending, investigating or providing evidence in connection with any
actual or threatened claims or otherwise. Every director or other officer of our group may also be provided with funds to meet, or do anything to enable a director or other officer of the Company to avoid incurring, expenditure of the nature
described in sections 205(1) or 206 of the Companies Act.
Exclusive Jurisdiction

Our articles of association provide that, unless we consent in writing to the selection of an alternative forum in the United States of America, the federal
district courts of the United States of America shall be the exclusive forum for the resolution of any complaint asserting a cause of action arising under the Securities Act. Save in respect of any cause of action arising under the Securities Act,
by subscribing for or acquiring shares, a shareholder submits all disputes between him or herself and us or our directors to the exclusive jurisdiction of the English courts.

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Other English Law Considerations

Mandatory Purchases and Acquisitions
Pursuant to
Sections 979 to 991 of the Companies Act, where a takeover offer has been made for us and the offeror has acquired or unconditionally contracted to acquire not less than 90% in value of the shares to which the offer relates and not less than 90% of
the voting rights carried by those shares, the offeror may give notice to the holder of any shares to which the offer relates which the offeror has not acquired or unconditionally contracted to acquire that he, she or it wishes to acquire, and is
entitled to so acquire, those shares on the same terms as the general offer. The offeror would do so by sending a notice to the outstanding minority shareholders telling them that it will compulsorily acquire their shares.

Such notice must be sent within three months of the last day on which the offer can be accepted in the prescribed manner. The
squeeze-out of the minority shareholders can be completed at the end of six weeks from the date the notice has been given, subject to the minority shareholders failing to successfully lodge an application to
the court to prevent such squeeze-out any time prior to the end of those six weeks following which the offeror can execute a transfer of the outstanding shares in its favor and pay the consideration to us,
which would hold the consideration on trust for the outstanding minority shareholders. The consideration offered to the outstanding minority shareholders whose shares are compulsorily acquired under the Companies Act must, in general, be the same as
the consideration that was available under the takeover offer.
Sell Out

The Companies Act also gives our minority shareholders a right to be bought out in certain circumstances by an offeror who has made a takeover offer for all of
our shares. The holder of shares to which the offer relates, and who has not otherwise accepted the offer, may require the offeror to acquire his, her or its shares if, prior to the expiry of the acceptance period for such offer, (1) the
offeror has acquired or unconditionally agreed to acquire not less than 90% in value of the voting shares, and (2) not less than 90% of the voting rights carried by those shares. The offeror may impose a time limit on the rights of minority
shareholders to be bought out that is not less than three months after the end of the acceptance period. If a shareholder exercises his, her or its rights to be bought out, the offeror is required to acquire those shares on the terms of this offer
or on such other terms as may be agreed.
Disclosure of Interest in Shares

Pursuant to Part 22 of the Companies Act, we are empowered by notice in writing to any person whom we know or have reasonable cause to believe to be interested
in our shares, or at any time during the three years immediately preceding the date on which the notice is issued has been so interested, within a reasonable time to disclose to us particulars of that person’s interest and (so far as is within
such person’s knowledge) particulars of any other interest that subsists or subsisted in those shares.
Under our articles of association, if a
person defaults in supplying us with the required particulars in relation to the shares in question, or default shares, within the prescribed period of 14 days from the date of the service of notice, the directors may by notice direct that:

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in respect of the default shares, the relevant shareholder shall not be entitled to vote (either in person or by
proxy) at any general meeting or to exercise any other right conferred by a shareholding in relation to general meetings; and
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where the default shares represent at least 0.25% of their class, (a) any dividend or other money payable in
respect of the default shares shall be retained by us without liability to pay interest and/or (b) no transfers by the relevant shareholder of any default shares may be registered (unless the shareholder is not in default and the shareholder
provides a certificate, in a form satisfactory to the directors, to the effect that after due and careful enquiry the shareholder is satisfied that none of the shares to be transferred are default shares).
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Purchase of Own Shares

Under the laws of England and Wales, a limited company may only purchase its own shares out of the distributable profits of the company or the proceeds of a
fresh issue of shares made for the purpose of financing the purchase, provided that they are not restricted from doing so by their articles of association. A limited company may not purchase its own shares if, as a result of the purchase, there
would no longer be any issued shares of the company other than redeemable shares or shares held as treasury shares. Shares must be fully paid in order to be repurchased.

We may purchase our own fully paid shares pursuant to a purchase contract authorized by resolution of shareholders before the purchase takes place. Any
authority will not be effective if any shareholder from whom we propose to purchase shares votes on the resolution and the resolution would not have been passed if he, she or it had not done so. The resolution authorizing the purchase must specify a
date, not being later than five years after the passing of the resolution, on which the authority to purchase is to expire.
Distributions and
Dividends
Under the Companies Act, before a company can lawfully make a distribution or dividend, it must ensure that it has sufficient
distributable reserves (on a non-consolidated basis). The basic rule is that a company’s profits available for the purpose of making a distribution are its accumulated, realized profits, so far as not
previously utilized by distribution or capitalization, less its accumulated, realized losses, so far as not previously written off in a reduction or reorganization of capital duly made. The requirement to have sufficient distributable reserves
before a distribution or dividend can be paid applies to us and to each of our subsidiaries that has been incorporated under the laws of England and Wales.

It is not sufficient that we, as a public company, have made a distributable profit for the purpose of making a distribution. An additional capital
maintenance requirement is imposed on us to ensure that the net worth of the company is at least equal to the amount of its capital. A public company can only make a distribution:

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if, at the time that the distribution is made, the amount of its net assets (that is, the total excess of assets
over liabilities) is not less than the total of its called up share capital and undistributable reserves; and
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if, and to the extent that, the distribution itself, at the time that it is made, does not reduce the amount of
the net assets to less than that total.
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City Code on Takeovers and Mergers

The UK City Code on Takeovers and Mergers, or the Takeover Code, provides a framework within which takeovers of companies subject to it are conducted.

Following the cancellation of admission of our ordinary shares to trading on the AIM market of the London Stock Exchange in November 2021, or the AIM
Delisting, and under transitional provisions that apply until February 2027, the Takeover Code will only apply to us if we are considered by the Panel on Takeovers and Mergers, or the Takeover Panel, to have our place of central management and
control in the United Kingdom (or the Channel Islands or the Isle of Man). This is known as the “residency test”. The way in which the test for central management and control is applied for the purposes of the Takeover Code may be
different from the way it is applied by the United Kingdom tax authorities. Under the Takeover Code, the Takeover Panel looks to where the majority of the directors of the company are resident, amongst other factors, for the purposes of determining
where the company has its place of central management and control.
Based on the current composition of our board of directors, we believe that we are not
currently subject to the Takeover Code. As a result, our shareholders are not currently entitled to the benefit of certain takeover offer protections provided under the Takeover Code. We believe that this position is unlikely to change until the end
of

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the transitional period, but, in accordance with good practice, we will review the situation on a regular basis and consult with the Takeover Panel if there is any change in our circumstances
which may have a bearing on whether the Takeover Panel would determine our place of central management and control to be in the United Kingdom.
Following
the end of the transitional period, with effect from February 3, 2027, the “residency test” will be abolished in its entirety and we expect we will no longer be subject to the jurisdiction of the Takeover Code at all from that time,
unless our securities are listed in the United Kingdom.
We have incorporated certain takeover protections in our articles of association, which apply in
circumstances where the Takeover Code does not apply to the company. A resolution was passed at the company’s annual general meeting held on June 26, 2025, to approve the continued application of these provisions until the 2026 annual
general meeting. Our board of directors has proposed a similar resolution at the 2026 annual general meeting to be held on June 16, 2026, which, if approved by shareholders, would extend the application of these provisions until the 2027 annual
general meeting.
Exchange Controls
There are
no governmental laws, decrees, regulations or other legislation in the United Kingdom that may affect the import or export of capital, including the availability of cash and cash equivalents for use by us, or that may affect the remittance of
dividends, interest, or other payments by us to non-resident holders of our ordinary shares or ADSs representing our ordinary shares, other than withholding tax requirements. There is no limitation imposed by
the laws of England and Wales or in our articles of association on the right of non-residents to hold or vote our shares.

Differences in Corporate Law
The applicable provisions
of the Companies Act differ from laws applicable to U.S. corporations and their shareholders. Set forth below is a summary of certain differences between the provisions of the Companies Act applicable to us and the General Corporation Law of the
State of Delaware relating to shareholders’ rights and protections. This summary is not intended to be a complete discussion of shareholder rights under the laws of Delaware and the laws of England and Wales.

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ENGLAND AND WALES
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DELAWARE
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Number of Directors |
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Under the Companies Act, a public limited company must have at least two directors and the number of directors may be fixed by or in the manner provided in a company’s articles of association. |
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Under Delaware law, a corporation must have at least one director and the number of directors shall be fixed by or in the manner provided in the bylaws. |

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Removal of Directors |
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Under the Companies Act, shareholders may remove a director without cause by an ordinary resolution (which is passed by a simple majority of those voting in person or by proxy at a general meeting) irrespective of any provisions of
any service contract the director has with the company, provided 28 clear days’ notice of the resolution has been given to the company and its shareholders. On receipt of notice of an intended resolution to remove a director, the company must
forthwith send a copy of the notice to the director concerned. Certain other procedural requirements under the Companies Act must also be followed such |
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Under Delaware law, any director or the entire board of directors may be removed, with or without cause, by the holders of a majority of the shares then entitled to vote at an election of directors, except (a) unless the
certificate of incorporation provides otherwise, in the case of a corporation whose board of directors is classified, shareholders may effect such removal only for cause, or (b) in the case of a corporation
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as allowing the director to make representations against his or her removal either at the meeting or in writing. |
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cumulative voting, if less than the entire board of directors is to be removed, no director may be removed without cause if the votes cast against his or her removal would be sufficient to elect him or her if then cumulatively voted
at an election of the entire board of directors, or, if there are classes of directors, at an election of the class of directors of which he or she is a part. |

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Vacancies on the Board of Directors |
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Under the laws of England and Wales, the procedure by which directors, other than a company’s initial directors, are appointed is generally set out in a company’s articles of association, provided that where two or more
persons are appointed as directors of a public limited company by resolution of the shareholders, resolutions appointing each director must be voted on individually. |
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Under Delaware law, vacancies and newly created directorships may be filled by a majority of the directors then in office (even though less than a quorum) or by a sole remaining director unless (a) otherwise provided in the
certificate of incorporation or by-laws of the corporation or (b) the certificate of incorporation directs that a particular class of stock is to elect such director, in which case a majority of the other
directors elected by such class, or a sole remaining director elected by such class, will fill such vacancy. |

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Annual General Meeting |
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Under the Companies Act, a public limited company must hold an annual general meeting in each six-month period following our annual accounting reference date. |
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Under Delaware law, the annual meeting of stockholders shall be held at such place, on such date and at such time as may be designated from time to time by the board of directors or as provided in the certificate of incorporation or
by the bylaws. |

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General Meeting |
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Under the Companies Act, a general meeting of the shareholders of a public limited company may be called by the directors.

Shareholders holding at least 5% of the paid-up
capital of the company carrying voting rights at general meetings (excluding any paid up capital held as treasury shares) can require the directors to call a general meeting and, if the directors fail to do so within a certain period, may themselves
convene a general meeting.
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Under Delaware law, special meetings of the stockholders may be called by the board of directors or by such person or persons as may be authorized by the certificate of incorporation or by the
bylaws. |

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DELAWARE
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Notice of General Meetings |
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Under the Companies Act, at least 21 clear days’ notice must be given for an annual general meeting and any resolutions to be proposed at the meeting. Subject to a company’s articles of association providing for a longer
period, at least 14 clear days’ notice is required for any other general meeting. In addition, certain matters, such as the removal of directors or auditors, require special notice, which is 28 clear days’ notice. The shareholders of a
company may in all cases consent to a shorter notice period, the proportion of shareholders’ consent required being 100% of those entitled to attend and vote in the case of an annual general meeting and, in the case of any other general
meeting, a majority in number of the members having a right to attend and vote at the meeting, being a majority who together hold not less than 95% in nominal value of the shares giving a right to attend and vote at the meeting (excluding any shares
held as treasury shares). |
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Under Delaware law, unless otherwise provided in the certificate of incorporation or bylaws, written notice of any meeting of the stockholders must be given to each stockholder entitled to vote at the meeting not less than 10 nor
more than 60 days before the date of the meeting and shall specify the place, date, hour, and purpose or purposes of the meeting. |

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Quorum |
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Subject to the provisions of a company’s articles of association, the Companies Act provides that two ‘qualifying persons’ present at a meeting (in person, by proxy or authorized representative under the Companies
Act (provided that the proxies and/or authorized representatives, represent different shareholders)) shall constitute |
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The certificate of incorporation or bylaws may specify the number of shares, the holders of which shall be present or represented by proxy at any meeting in order to constitute a quorum, but in no event shall a quorum consist of
less than one-third of the shares entitled to vote at the meeting. In the absence of such specification in |

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Proxy |
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Under the Companies Act, at any meeting of shareholders, a shareholder may designate another person to attend, speak and vote at the meeting on their behalf by proxy. |
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Under Delaware law, at any meeting of stockholders, a stockholder may designate another person to act for such stockholder by proxy, but no such proxy shall be voted or acted upon after three years from its date, unless the proxy
provides for a longer period. A director of a Delaware corporation may not issue a proxy representing the director’s voting rights as a director. |

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Preemptive Rights |
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Under the Companies Act, “equity securities,” being (1) shares in the company other than shares that, with respect to dividends and capital, carry a right to participate only up to a specified amount in a
distribution, referred to as “ordinary shares,” or (2) rights to subscribe for, or to convert securities into, ordinary shares, proposed to be allotted for cash must be offered first to the existing equity shareholders in |
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Under Delaware law, shareholders have no preemptive rights to subscribe to additional issues of stock or to any security convertible into such stock unless, and except to the extent that, such rights are expressly provided for in
the certificate of incorporation. |

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the company in proportion to the respective nominal value of their holdings, unless an exception applies or a special resolution to the contrary has been passed by shareholders in a general meeting or the articles of association
provide otherwise in each case in accordance with the provisions of the Companies Act. |
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Authority to Allot |
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Under the Companies Act, the directors of a company must not allot shares or grant of rights to subscribe for or to convert any security into shares unless an exception applies or an ordinary resolution to the contrary has been
passed by shareholders in a general meeting or the articles of association provide otherwise in each case in accordance with the provisions of the Companies Act. |
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Under Delaware law, if the corporation’s charter or certificate of incorporation so provides, the board of directors has the power to authorize the issuance of stock. It may authorize capital stock to be issued for
consideration consisting of cash, any tangible or intangible property or any benefit to the corporation or any combination thereof. It may determine the amount of such consideration by approving a formula. In the absence of actual fraud in the
transaction, the judgment of the directors as to the value of such consideration is conclusive. |

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Liability of Directors and Officers |
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Under the Companies Act, any provision, whether contained in a company’s articles of association or any contract or otherwise, that
purports to exempt a director of a company, to any extent, from any liability that would otherwise attach to him or her in connection with any negligence, default, breach of duty or breach of trust in relation to the company is void.

Any provision by which a company directly or indirectly provides an indemnity, to any
extent, for a director of the company or of an associated company against any liability attaching to him or her in connection with any negligence, default, breach of duty or breach of trust in relation to the company of which he or she is a director
is also void except as permitted by the Companies Act, which provides exceptions for the company to (a) purchase and maintain insurance against such liability; (b) provide a “qualifying third party indemnity” (being an
indemnity against liability incurred by the director to a person other than the company or an associated company or criminal proceedings in which he or she is convicted); and (c) provide a “qualifying pension scheme indemnity”
(being an indemnity against liability incurred in connection with our activities as trustee of an occupational pension plan).
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any breach of the director’s duty of loyalty to the corporation or its stockholders;

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acts or omissions not in good faith or that involve intentional misconduct or a knowing violation of law;

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intentional or negligent payment of unlawful dividends or stock purchases or redemptions; or

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any transaction from which the director derives an improper personal
benefit.

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Voting Rights |
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Under the laws of England and Wales, unless a poll is demanded by the shareholders of a company or is required by the chairman of the meeting or our articles of association, shareholders shall vote on all resolutions on a show of
hands. Under the Companies Act, a poll may be demanded by (a) not fewer than five shareholders having the right to vote on the resolution; (b) any shareholder(s) representing not less than 10% of the total voting rights of all the
shareholders having the right to vote on the resolution (excluding any voting rights attaching to treasury shares); or (c) any shareholder(s) holding shares in the company conferring a right to vote on the resolution (excluding any voting
rights attaching to treasury shares) being shares on which an aggregate sum has been paid up equal to not less than 10% of the total sum paid up on all the shares conferring that right. A company’s articles of association may provide more
extensive rights for shareholders to call a poll. |
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Delaware law provides that, unless otherwise provided in the certificate of incorporation, each stockholder is entitled to one vote for each share of capital stock held by such stockholder. |

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Under the laws of England and Wales, an ordinary resolution is passed on a show of hands if it is approved by a simple majority (more than 50%) of the votes cast by shareholders present (in person or by proxy) and entitled to vote.
If a poll is demanded, an ordinary resolution is passed if it is approved by holders representing a simple majority of the total voting rights of shareholders present, in person or by proxy, who, being entitled to vote, vote on the resolution.
Special resolutions require the affirmative vote of not less than 75% of the votes cast by shareholders present, in person or by proxy, at the meeting. If a poll is demanded, a special resolution is passed if it is approved by holders representing
not less than 75% of the total voting rights of shareholders in person or by proxy who, being entitled to vote, vote on the resolution. |
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Shareholder Vote on Certain Transactions |
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The Companies Act provides for schemes of arrangement, which are arrangements or compromises between a company and any class of shareholders
or creditors and used in certain types of reconstructions, amalgamations, capital reorganizations, or takeovers. These arrangements require:

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the approval at a shareholders’ or creditors’ meeting convened by order of the court, of a majority in number of shareholders or
creditors representing 75% in value of the capital held by, or debt owed to, the class of shareholders or creditors, or class thereof present and voting, either in person or by proxy; and

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the approval of the court.

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Generally, under Delaware law, unless the certificate of incorporation provides for the vote of a larger portion of the stock, completion of
a merger, consolidation, sale, lease or exchange of all or substantially all of a corporation’s assets or dissolution requires:

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the approval of the board of directors; and

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approval by the vote of the holders of a majority of the outstanding stock or, if
the

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certificate of incorporation provides for more or less than one vote per share, a majority of the votes of the outstanding stock of a corporation entitled to vote on the matter. |

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Standard of Conduct for Directors |
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Under the laws of England and Wales, a director owes various statutory and fiduciary duties to the company, including:

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to act in the way he or she considers, in good faith, would be most likely to promote the success of the company for the benefit of its members as a
whole(and in doing so have regard (amongst other matters) to: (i) the likely consequences of any decision in the long-term, (ii) the interests of the company’s employees, (iii) the need to foster the company’s business
relationships with suppliers, customers and others, (iv) the impact of the company’s operations on the community and the environment, (v) the desirability to maintain a reputation for high standards of business conduct, and
(vi) the need to act fairly as between members of the company); avoid a situation in which he or she has, or can have, a direct or indirect interest that conflicts, or possibly conflicts, with the interests of the company;

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Delaware law does not contain specific provisions setting forth the standard of conduct of a director. The scope of the fiduciary duties of directors is generally determined by the courts of the State of Delaware. In general,
directors have a duty to act without self-interest, on a well-informed basis and in a manner they reasonably believe to be in the best interest of the stockholders. |

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to act in accordance with our constitution and only exercise his or her powers for the purposes for which they are conferred;

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to exercise independent judgment;

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to exercise reasonable care, skill, and diligence;

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not to accept benefits from a third party conferred by reason of his or her being a director or doing, or not doing, anything as a director;
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a duty to declare any interest that he or she has, whether directly or indirectly, in a proposed or existing transaction or arrangement with the
company.

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Directors of a Delaware corporation owe fiduciary duties of care and loyalty to the corporation and to its shareholders. The duty of care generally requires that a director act in good faith, with the care that an ordinarily prudent
person would exercise under similar circumstances. Under this duty, a director must inform himself or herself of all material information reasonably available regarding a significant transaction. The duty of loyalty requires that a director act in a
manner he or she reasonably believes to be in the best interests of the corporation. He or she must not use his or her corporate position for personal gain or advantage. In general, but subject to certain
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actions of a director are presumed to have been made on an informed basis, in good faith and in the honest belief that the action taken was
in the best interests of the corporation. However, this presumption may be rebutted by evidence of a breach of one of the fiduciary duties. Delaware courts have also imposed a heightened standard of conduct upon directors of a Delaware corporation
who take any action designed to defeat a threatened change in control of the corporation.

In addition, under Delaware law, when the board of directors of a Delaware corporation approves the sale or break-up of
a corporation, the board of directors may, in certain circumstances, have a duty to obtain the highest value reasonably available to the shareholders.
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Stockholder Suits |
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Under the laws of England and Wales, generally, the company, rather than its shareholders, is the proper claimant in an action in respect of a wrong done to the company or where there is an irregularity in our internal management.
Notwithstanding this general position, the Companies Act provides that (1) a court may allow a shareholder to bring a derivative claim (that is, an action in respect of and on behalf of the company) in respect of a cause of action arising from
a director’s negligence, default, breach of duty or breach of trust and (2) a shareholder may bring a claim for a court order where our affairs have been or are being conducted in a manner that is unfairly prejudicial to some of its
shareholders. |
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Under Delaware law, a stockholder may initiate a derivative action to enforce a right of a corporation if the corporation fails to enforce
the right itself. The complaint must:

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state that the plaintiff was a stockholder at the time of the transaction of which the plaintiff complains or that the plaintiffs shares thereafter
devolved on the plaintiff by operation of law; and

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allege with particularity the efforts made by the plaintiff to obtain the action the plaintiff desires from the directors and the reasons for the
plaintiff’s failure to obtain the action; or

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state the reasons for not making the effort.

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ENGLAND AND WALES
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DELAWARE
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Additionally, the plaintiff must remain a stockholder through the
duration of the derivative suit. The action will not be dismissed or compromised without the approval of the Delaware Court of Chancery.
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Nasdaq Global Market Listing

Our ADSs are listed on The Nasdaq Global Market under the trading symbol “SLN.”

Registrar of Shares; Depositary for ADSs

Our share register is maintained by MUFG Corporate Markets. The share register reflects only registered holders of our ordinary shares. Our ordinary shares
are not listed for trading on any securities exchange, and we do not plan to list our ordinary shares on any securities exchange.
Holders of ADSs
representing our ordinary shares are not treated as our shareholders and their names will therefore not be entered in our share register. The Bank of New York Mellon acts as the depositary for the ADSs representing our ordinary shares and the
custodian for ordinary shares represented by ADSs is The Bank of New York Mellon, acting through an office located in England. Holders of ADSs representing our ordinary shares have a right to receive the ordinary shares underlying such ADSs upon
surrender and cancellation of the ADSs. For discussion on ADSs representing our ordinary shares and rights of ADS holders, see the section titled “Description of American Depositary Shares.”

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DESCRIPTION OF AMERICAN DEPOSITARY SHARES

American Depositary Shares
The Bank of New York Mellon
is the depositary for the ADSs representing our ordinary shares. The Bank of New York Mellon’s depositary offices are located at 240 Greenwich Street, New York, New York 10286. ADSs represent ownership interests in securities that are on
deposit with the depositary. ADSs may be represented by certificates that are commonly known as American Depositary Receipts, or ADRs. The depositary typically appoints a custodian to safekeep the securities on deposit. Each ADS will represent three
ordinary shares (or a right to receive three ordinary shares) deposited with The Bank of New York Mellon, acting through an office located in the United Kingdom, as custodian. Each ADS will also represent any other securities, cash or other property
that may be held by the depositary. The deposited ordinary shares together with any other securities, cash or other property held by the depositary are referred to as the deposited securities.

You may hold ADSs either (A) directly (i) by having an ADR, which is a certificate evidencing a specific number of ADSs, registered in your name, or
(ii) by having uncertificated ADSs registered in your name, or (B) indirectly by holding a security entitlement in ADSs through your broker or other financial institution that is a direct or indirect participant in The Depository Trust
Company, also called DTC. If you hold ADSs directly, you are a registered ADS holder, also referred to as an ADS holder. This description assumes you are an ADS holder. If you hold the ADSs indirectly, you must rely on the procedures of your broker
or other financial institution to assert the rights of ADS holders described in this section. You should consult with your broker or financial institution to find out what those procedures are.

Registered holders of uncertificated ADSs will receive statements from the depositary confirming their holdings.

As an ADS holder, we will not treat you as one of our shareholders, and you will not have shareholder rights. Shareholder rights are governed by the laws of
England and Wales. The depositary will be the holder of the ordinary shares underlying your ADSs. As a registered holder of ADSs, you will have ADS holder rights. A deposit agreement among us, the depositary, ADS holders and all other persons
indirectly or beneficially holding ADSs sets out ADS holder rights as well as the rights and obligations of the depositary. New York law governs the deposit agreement and the ADSs.

We are providing you with a summary description of the material terms of the ADSs and of your material rights as an owner of ADSs. Please remember that
summaries by their nature lack the precision of the information summarized and that the rights and obligations of an owner of ADSs has been determined by reference to the terms of the deposit agreement and not by this summary. We urge you to review
the deposit agreement in its entirety. The portions of this summary description that are italicized describe matters that may be relevant to the ownership of ADSs but that may not be contained in the deposit agreement. For more complete information,
you should read the entire deposit agreement and the form of ADR, which are filed as Exhibits 4.1 and 4.2, respectively.
Dividends and Other
Distributions
How will you receive dividends and other distributions on the ordinary shares?

The depositary has agreed to pay or distribute to ADS holders the cash dividends or other distributions it or the custodian receives on ordinary shares or
other deposited securities, upon payment or deduction of its fees and expenses, or withholding of taxes. You will receive these distributions in proportion to the number of ordinary shares your ADSs represent.

Cash
The depositary will convert any cash
dividend or other cash distribution we pay on the ordinary shares into U.S. dollars, if it can do so on a reasonable basis and can transfer the U.S. dollars to the United States. If that is not

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possible or if any government approval is needed and cannot be obtained, the deposit agreement allows the depositary to distribute the foreign currency only to those ADS holders to whom it is
possible to do so. It will hold the foreign currency it cannot convert for the account of the ADS holders who have not been paid. It will not invest the foreign currency and it will not be liable for any interest.

Before making a distribution, any withholding taxes, or other governmental charges that must be paid will be deducted. See “Payment of Taxes.” The
depositary will distribute only whole U.S. dollars and cents and will round fractional cents to the nearest whole cent. If the exchange rates fluctuate during a time when the depositary cannot convert the foreign currency, you may lose some of
the value of the distribution.
Ordinary Shares

The depositary may distribute additional ADSs representing any ordinary shares we distribute as a dividend or free distribution. The depositary will only
distribute whole ADSs. It will sell ordinary shares which would require it to deliver a fraction of an ADS (or ADSs representing those ordinary shares) and distribute the net proceeds in the same way as it does with cash. If the depositary does not
distribute additional ADSs, the outstanding ADSs will also represent the new ordinary shares. The depositary may sell a portion of the distributed ordinary shares (or ADSs representing those ordinary shares) sufficient to pay its fees and expenses
in connection with that distribution.
Rights to Purchase Additional Ordinary Shares

If we offer holders of our securities any rights to subscribe for additional ordinary shares or any other rights, the depositary may (i) exercise those
rights on behalf of ADS holders, (ii) distribute those rights to ADS holders or (iii) sell those rights and distribute the net proceeds to ADS holders, in each case after deduction or upon payment of its fees and expenses. To the extent
the depositary does not do any of those things, it will allow the rights to lapse. In that case, you will receive no value for them. The depositary will exercise or distribute rights only if we ask it to and provide satisfactory assurances to
the depositary that it is legal to do so. If the depositary will exercise rights, it will purchase the securities to which the rights relate and distribute those securities or, in the case of ordinary shares, new ADSs representing the new ordinary
shares, to subscribing ADS holders, but only if ADS holders have paid the exercise price to the depositary. U.S. securities laws may restrict the ability of the depositary to distribute rights or ADSs or other securities issued on exercise of rights
to all or certain ADS holders, and the securities distributed may be subject to restrictions on transfer.
Other Distributions

The depositary will send to ADS holders anything else we distribute on deposited securities by any means it thinks is legal, fair and practical. If it cannot
make the distribution in that way, the depositary has a choice. It may decide to sell what we distributed and distribute the net proceeds, in the same way as it does with cash. Or, it may decide to hold what we distributed, in which case ADSs will
also represent the newly distributed property. However, the depositary is not required to distribute any securities (other than ADSs) to ADS holders unless it receives satisfactory evidence from us that it is legal to make that distribution. The
depositary may sell a portion of the distributed securities or property sufficient to pay its fees and expenses in connection with that distribution. U.S. securities laws may restrict the ability of the depositary to distribute securities to all or
certain ADS holders, and the securities distributed may be subject to restrictions on transfer.
The depositary is not responsible if it decides that it
is unlawful or impractical to make a distribution available to any ADS holders. We have no obligation to register ADSs, ordinary shares, rights or other securities under the Securities Act. We also have no obligation to take any other action to
permit the distribution of ADSs, ordinary shares, rights or anything else to ADS holders. This means that you may not receive the distributions we make on our ordinary shares or any value for them if it is illegal or impractical for us to
make them available to you .

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Deposit, Withdrawal and Cancellation

How are ADSs issued?
The depositary will deliver
ADSs if you or your broker deposits ordinary shares or evidence of rights to receive ordinary shares with the custodian. Upon payment of its fees and expenses and of any taxes or charges, such as stamp taxes or stock transfer taxes or fees, the
depositary will register the appropriate number of ADSs in the names you request and will deliver the ADSs to or upon the order of the person or persons that made the deposit.

How can ADS holders withdraw the deposited securities?

You may surrender your ADSs to the depositary for the purpose of withdrawal. Upon payment of its fees and expenses and of any taxes or charges, such as stamp
taxes or stock transfer taxes or fees, the depositary will deliver the ordinary shares and any other deposited securities underlying the ADSs to the ADS holder or a person the ADS holder designates at the office of the custodian. Or, at your
request, risk and expense, the depositary will deliver the deposited securities at its office, if feasible. However, the depositary is not required to accept surrender of ADSs to the extent it would require delivery of a fraction of a deposited
share or other security. The depositary may charge you a fee and its expenses for instructing the custodian regarding delivery of deposited securities.

How do ADS holders interchange between certificated ADSs and uncertificated ADSs?

You may surrender your ADR to the depositary for the purpose of exchanging your ADR for uncertificated ADSs. The depositary will cancel that ADR and will send
to the ADS holder a statement confirming that the ADS holder is the registered holder of uncertificated ADSs. Upon receipt by the depositary of a proper instruction from a registered holder of uncertificated ADSs requesting the exchange of
uncertificated ADSs for certificated ADSs, the depositary will execute and deliver to the ADS holder an ADR evidencing those ADSs.
Voting Rights

How do you vote?
ADS holders may instruct
the depositary how to vote the number of deposited shares their ADSs represent. If we request the depositary to solicit your voting instructions (and we are not required to do so), the depositary will notify you of a shareholders’ meeting and
send or make voting materials available to you. Those materials will describe the matters to be voted on and explain how ADS holders may instruct the depositary how to vote. For instructions to be valid, they must reach the depositary by a date set
by the depositary. The depositary will try, as far as practical, subject to the laws of England and Wales and the provisions of our articles of association or similar documents, to vote or to have its agents vote the ordinary shares or other
deposited securities as instructed by ADS holders. If we do not request the depositary to solicit your voting instructions, you can still send voting instructions, and, in that case, the depositary may try to vote as you instruct, but it is not
required to do so.
Except by instructing the depositary as described above, you will not be able to exercise voting rights unless you surrender your ADSs
and withdraw the ordinary shares. However, you may not know about the meeting enough in advance to withdraw the ordinary shares. In any event, the depositary will not exercise any discretion in voting deposited securities and it will only vote or
attempt to vote as instructed.
We cannot assure you that you will receive the voting materials in time to ensure that you can instruct the depositary to
vote the ordinary shares represented by your ADSs. In addition, the depositary and its agents are not responsible for failing to carry out voting instructions or for the manner of carrying out voting instructions. This means that you may not be
able to exercise voting rights and there may be nothing you can do if the ordinary shares represented by your ADSs are not voted as you requested.

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In order to give you a reasonable opportunity to instruct the depositary as to the exercise of voting rights
relating to deposited securities, if we request the depositary to act, we agree to give the depositary notice of any such meeting and details concerning the matters to be voted upon at least 30 days in advance of the meeting date.

Fees and Expenses
As an ADS holder, you will be required
to pay the following fees under the terms of the deposit agreement:

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PERSONS DEPOSITING OR WITHDRAWING
ORDINARY
SHARES
OR ADS HOLDERS MUST PAY:
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FOR:
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$5.00 (or less) per 100 ADSs (or portion of 100 ADSs) |
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Issuance of ADSs, including issuances resulting from a distribution of ordinary shares or rights or other property |

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Cancellation of ADSs for the purpose of withdrawal, including if the deposit agreement terminates |

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$.05 (or less) per ADS |
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Any cash distribution to ADS holders |

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A fee equivalent to the fee that would be payable if securities distributed to you had been ordinary shares and the ordinary shares had been deposited for issuance of ADSs |
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Distribution of securities distributed to holders of deposited securities (including rights) that are distributed by the depositary to ADS holders |

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$.05 (or less) per ADS per calendar year |
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Depositary services |

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Registration or transfer fees |
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Transfer and registration of ordinary shares on our share register to or from the name of the depositary or its agent when you deposit or withdraw ordinary shares |

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Expenses of the depositary |
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Cable (including SWIFT) and facsimile transmissions (when expressly provided in the deposit agreement)

Converting foreign currency to U.S. dollars
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Taxes and other governmental charges the depositary or the custodian has to pay on any ADSs or ordinary shares underlying ADSs, such as stock transfer taxes, stamp duty or withholding taxes |
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As necessary |

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Any charges incurred by the depositary or its agents for servicing the deposited securities |
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The depositary collects its fees for delivery and surrender of ADSs directly from investors depositing ordinary shares or
surrendering ADSs for the purpose of withdrawal or from intermediaries acting for them. The depositary collects fees for making distributions to investors by deducting those fees from the amounts distributed or by selling a portion of distributable
property to pay the fees. The depositary may collect its annual fee for depositary services by deduction from cash distributions or by directly billing investors or by charging the book-entry system accounts of participants acting for them. The
depositary may collect any of its fees by deduction from any cash distribution payable (or by selling a portion of securities or other property distributable) to ADS holders that are obligated to pay those fees. The depositary may generally refuse
to provide fee-attracting services until its fees for those services are paid.
From time to time, the depositary
may make payments to us to reimburse us for costs and expenses generally arising out of establishment and maintenance of the ADS program, waive fees and expenses for services provided

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to us by the depositary or share revenue from the fees collected from ADS holders. In performing its duties under the deposit agreement, the depositary may use brokers, dealers, foreign currency
dealers or other service providers that are owned by or affiliated with the depositary and that may earn or share fees, spreads or commissions.
The
depositary may convert currency itself or through any of its affiliates, or the custodian or we may convert currency and pay U.S. dollars to the depositary. Where the depositary converts currency itself or through any of its affiliates, the
depositary acts as principal for its own account and not as agent, advisor, broker or fiduciary on behalf of any other person and earns revenue, including, without limitation, transaction spreads, that it will retain for its own account. The revenue
is based on, among other things, the difference between the exchange rate assigned to the currency conversion made under the deposit agreement and the rate that the depositary or its affiliate receives when buying or selling foreign currency for its
own account. The depositary makes no representation that the exchange rate used or obtained by it or its affiliate in any currency conversion under the deposit agreement will be the most favorable rate that could be obtained at the time or that the
method by which that rate will be determined will be the most favorable to ADS holders, subject to the depositary’s obligation to act without negligence or bad faith. The methodology used to determine exchange rates used in currency
conversions made by the depositary is available upon request.
Where the custodian converts currency, the custodian has no obligation to obtain the most
favorable rate that could be obtained at the time or to ensure that the method by which that rate will be determined will be the most favorable to ADS holders, and the depositary makes no representation that the rate is the most favorable rate and
will not be liable for any direct or indirect losses associated with the rate. In certain instances, the depositary may receive dividends or other distributions from us in U.S. dollars that represent the proceeds of a conversion of foreign currency
or translation from foreign currency at a rate that was obtained or determined by us and, in such cases, the depositary will not engage in, or be responsible for, any foreign currency transactions and neither it nor we make any representation that
the rate obtained or determined by us is the most favorable rate and neither it nor we will be liable for any direct or indirect losses associated with the rate.

Payment of Taxes
You will be responsible for any taxes
or other governmental charges payable on your ADSs or on the deposited securities represented by any of your ADSs. The depositary may refuse to register any transfer of your ADSs or allow you to withdraw the deposited securities represented by your
ADSs until those taxes or other charges are paid. It may apply payments owed to you or sell deposited securities represented by your ADSs to pay any taxes owed and you will remain liable for any deficiency. If the depositary sells deposited
securities, it will, if appropriate, reduce the number of ADSs to reflect the sale and pay to ADS holders any proceeds, or send to ADS holders any property, remaining after it has paid the taxes.

Tender and Exchange Offers; Redemption, Replacement or Cancellation of Deposited Securities

The depositary will not tender deposited securities in any voluntary tender or exchange offer unless instructed to do so by an ADS holder surrendering ADSs and
subject to any conditions or procedures the depositary may establish.
If deposited securities are redeemed for cash in a transaction that is mandatory
for the depositary as a holder of deposited securities, the depositary will call for surrender of a corresponding number of ADSs and distribute the net redemption money to the holders of called ADSs upon surrender of those ADSs.

If there is any change in the deposited securities such as a sub-division, consolidation or other reclassification, or
any merger, scheme of arrangement, recapitalization or reorganization affecting the issuer of deposited securities in which the depositary receives new securities in exchange for or in lieu of the old deposited securities, the depositary will hold
those replacement securities as deposited securities under the deposit agreement. However,

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if the depositary decides it would not be lawful and practical to hold the replacement securities because those securities could not be distributed to ADS holders or for any other reason, the
depositary may instead sell the replacement securities and distribute the net proceeds upon surrender of the ADSs.
If there is a replacement of the
deposited securities and the depositary will continue to hold the replacement securities, the depositary may distribute new ADSs representing the new deposited securities or ask you to surrender your outstanding ADSs in exchange for new ADSs
identifying the new deposited securities.
If there are no deposited securities underlying ADSs, including if the deposited securities are cancelled, or
if the deposited securities underlying ADSs have become apparently worthless, the depositary may call for surrender of those ADSs or cancel those ADSs upon notice to the ADS holders.

Amendment and Termination
How may the deposit
agreement be amended?
We may agree with the depositary to amend the deposit agreement and the ADRs without your consent for any reason. If an
amendment adds or increases fees or charges, except for taxes and other governmental charges or expenses of the depositary for registration fees, facsimile costs, delivery charges or similar items, or prejudices a substantial right of ADS holders,
it will not become effective for outstanding ADSs until 30 days after the depositary notifies ADS holders of the amendment. At the time an amendment becomes effective, you are considered, by continuing to hold your ADSs, to agree to the amendment
and to be bound by the ADRs and the deposit agreement as amended .
How may the deposit agreement be terminated?

The depositary will initiate termination of the deposit agreement if we instruct it to do so. The depositary may initiate termination of the deposit agreement
if:

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60 days have passed since the depositary told us it wants to resign but a successor depositary has not been
appointed and accepted its appointment;
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we delist the ADSs from an exchange in the United States on which they were listed and, within 30 days, do not
list the ADSs on another exchange in the United States or make arrangements for trading of ADSs on the U.S. over-the-counter market;
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we delist our ordinary shares from an exchange outside the United States on which they were listed and do not
list the ordinary shares on another exchange outside the United States;
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the depositary has reason to believe the ADSs have become, or will become, ineligible for registration on Form F-6 under the Securities Act of 1933;
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we appear to be insolvent or enter insolvency proceedings;
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all or substantially all the value of the deposited securities has been distributed either in cash or in the form
of securities;
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there are no deposited securities underlying the ADSs or the underlying deposited securities have become
apparently worthless; or
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there has been a replacement of deposited securities.
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If the deposit agreement will terminate, the depositary will notify ADS holders at least 90 days before the termination date. At any time after the
termination date, the depositary may sell the deposited securities. After that, the depositary will hold the money it received on the sale, as well as any other cash it is holding under the deposit agreement, unsegregated and without liability for
interest, for the pro rata benefit of the ADS holders that have not surrendered their ADSs. Normally, the depositary will sell as soon as practicable after the termination date.

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After the termination date and before the depositary sells, ADS holders can still surrender their ADSs and
receive delivery of deposited securities, except that the depositary may refuse to accept a surrender for the purpose of withdrawing deposited securities or reverse previously accepted surrenders of that kind that have not settled if it would
interfere with the selling process. The depositary may refuse to accept a surrender for the purpose of withdrawing sale proceeds until all the deposited securities have been sold. The depositary will continue to collect distributions on deposited
securities, but , after the termination date, the depositary is not required to register any transfer of ADSs or distribute any dividends or other distributions on deposited securities to the ADSs holder (until they surrender their ADSs) or
give any notices or perform any other duties under the deposit agreement except as described in this paragraph.
Limitations on Obligations and
Liability
Limits on our Obligations and the Obligations of the Depositary; Limits on Liability to Holders of ADSs

The deposit agreement expressly limits our obligations and the obligations of the depositary. It also limits our liability and the liability of the depositary.
We and the depositary:

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are only obligated to take the actions specifically set forth in the deposit agreement without negligence or bad
faith, and the depositary will not be a fiduciary or have any fiduciary duty to holders of ADSs;
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are not liable if we are or it is prevented or delayed by law or by events or circumstances beyond our or its
ability to prevent or counteract with reasonable care or effort from performing our or its obligations under the deposit agreement;
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are not liable if we or it exercises discretion permitted under the deposit agreement;
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are not liable for the inability of any holder of ADSs to benefit from any distribution on deposited securities
that is not made available to holders of ADSs under the terms of the deposit agreement, or for any special, consequential or punitive damages for any breach of the terms of the deposit agreement;
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have no obligation to become involved in a lawsuit or other proceeding related to the ADSs or the deposit
agreement on your behalf or on behalf of any other person;
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may rely upon any documents we believe or it believes in good faith to be genuine and to have been signed or
presented by the proper person;
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are not liable for the acts or omissions of any securities depository, clearing agency or settlement system; and

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the depositary has no duty to make any determination or provide any information as to our tax status, or any
liability for any tax consequences that may be incurred by ADS holders as a result of owning or holding ADSs or be liable for the inability or failure of an ADS holder to obtain the benefit of a foreign tax credit, reduced rate of withholding or
refund of amounts withheld in respect of tax or any other tax benefit.
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In the deposit agreement, we and the depositary agree to
indemnify each other under certain circumstances.
Requirements for Depositary Actions

Before the depositary will deliver or register a transfer of ADSs, make a distribution on ADSs, or permit withdrawal of ordinary shares, the depositary may
require:

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payment of stock transfer or other taxes or other governmental charges and transfer or registration fees charged
by third parties for the transfer of any ordinary shares or other deposited securities;
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satisfactory proof of the identity and genuineness of any signature or other information it deems necessary; and

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compliance with regulations it may establish, from time to time, consistent with the deposit agreement, including
presentation of transfer documents.
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The depositary may refuse to deliver ADSs or register transfers of ADSs when the transfer books of
the depositary or our transfer books are closed or at any time if the depositary or we think it advisable to do so.
Your Right to Receive the Ordinary
Shares Underlying your ADSs
ADS holders have the right to cancel their ADSs and withdraw the underlying ordinary shares at any time except:

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when temporary delays arise because: (i) the depositary has closed its transfer books or we have closed our
transfer books; (ii) the transfer of ordinary shares is blocked to permit voting at a shareholders’ meeting; or (iii) we are paying a dividend on our ordinary shares;
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when you owe money to pay fees, taxes and similar charges; or
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when it is necessary to prohibit withdrawals in order to comply with any laws or governmental regulations that
apply to ADSs or to the withdrawal of ordinary shares or other deposited securities.
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This right of withdrawal may not be limited by any
other provision of the deposit agreement.
Direct Registration System

In the deposit agreement, all parties to the deposit agreement acknowledge that the Direct Registration System, also referred to as DRS, and Profile
Modification System, also referred to as Profile, will apply to the ADSs. DRS is a system administered by DTC that facilitates interchange between registered holding of uncertificated ADSs and holding of security entitlements in ADSs through DTC and
a DTC participant. Profile is a feature of DRS that allows a DTC participant, claiming to act on behalf of a registered holder of uncertificated ADSs, to direct the depositary to register a transfer of those ADSs to DTC or its nominee and to deliver
those ADSs to the DTC account of that DTC participant without receipt by the depositary of prior authorization from the ADS holder to register that transfer.

In connection with and in accordance with the arrangements and procedures relating to DRS/Profile, the parties to the deposit agreement understand that the
depositary will not determine whether the DTC participant that is claiming to be acting on behalf of an ADS holder in requesting registration of transfer and delivery as described in the paragraph above has the actual authority to act on behalf of
the ADS holder (notwithstanding any requirements under the Uniform Commercial Code). In the deposit agreement, the parties agree that the depositary’s reliance on and compliance with instructions received by the depositary through the
DRS/Profile system and in accordance with the deposit agreement will not constitute negligence or bad faith on the part of the depositary.
Shareholder
Communications; Inspection of Register of Holders of ADSs
The depositary will make available for your inspection at its office all communications that
it receives from us as a holder of deposited securities that we make generally available to holders of deposited securities. The depositary will send you copies of those communications or otherwise make those communications available to you if we
ask it to. You have a right to inspect the register of holders of ADSs, but not for the purpose of contacting those holders about a matter unrelated to our business or the ADSs.

Jury Trial Waiver
The deposit agreement provides that,
to the extent permitted by law, ADS holders waive the right to a jury trial of any claim they may have against us or the depositary arising out of or relating to our ordinary shares, the ADSs or the deposit agreement, including any claim under the
U.S. federal securities laws. If we or the depositary opposed a jury trial demand based on the waiver, the court would determine whether the waiver was enforceable in the facts and circumstances of that case in accordance with applicable case law.

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You will not, by agreeing to the terms of the deposit agreement, be deemed to have waived our or the
depositary’s compliance with U.S. federal securities laws or the rules and regulations promulgated thereunder.
Each holder of ADSs may be required
from time to time to provide certain information, including proof of taxpayer status, residence and beneficial ownership (as applicable), from time to time and in a timely manner as we, the depositary or the custodian may deem necessary or proper to
fulfill obligations under applicable law.

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MATERIAL TAX CONSIDERATIONS

A general summary of certain tax considerations relating to the purchase, ownership and disposition of any of the securities offered by this prospectus will
be set forth or incorporated by reference in a prospectus supplement relating to the offering of those securities.

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LEGAL MATTERS

Unless the applicable prospectus supplement indicates otherwise, the validity of the securities in respect of which this prospectus is being delivered and
certain legal matters with respect to England and Wales will be passed upon for us by Cooley (UK) LLP, London, England. Certain matters in respect of U.S. securities laws may be opined upon by Cooley LLP, New York, New York. Additional legal matters
may be passed upon for any underwriters, dealers or agents by counsel that we will name in the applicable prospectus supplement.
EXPERTS
The financial statements incorporated in this prospectus by reference to the Annual Report on Form
10-K for the year ended December 31, 2025 have been so incorporated in reliance on the report (which contains an emphasis of matter paragraph relating to the Company’s requirement for additional
financing to fund future research and development efforts as described in Note 2.5 to the consolidated financial statements) of PricewaterhouseCoopers LLP, an independent registered public accounting firm, given on the authority of said firm as
experts in auditing and accounting.
The registered business address of PricewaterhouseCoopers LLP is 1 Embankment Place, London, WC2N 6RH, United
Kingdom.

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SERVICE OF PROCESS AND ENFORCEMENT OF LIABILITIES

We are incorporated and currently existing under the laws of England and Wales. In addition, certain of our directors and officers reside outside of the
United States and most of the assets of our non-U.S. subsidiaries are located outside of the United States. As a result, it may be difficult for investors to effect service of process on us or those persons in
the United States or to enforce in the United States judgments obtained in U.S. courts against us or those persons based on the civil liability or other provisions of the U.S. securities laws or other laws.

In addition, uncertainty exists as to whether the courts of England and Wales would:

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recognize or enforce judgments of U.S. courts obtained against us or our directors or officers predicated upon
the civil liabilities provisions of the securities laws of the United States or any state in the United States; or
|

|
• |
|
entertain original actions brought in England and Wales against us or our directors or officers predicated upon
the securities laws of the United States or any state in the United States.
|

We have been advised by Cooley LLP and Cooley (UK) LLP that
there is currently no treaty in force between (i) the United States and (ii) the United Kingdom providing for reciprocal recognition and enforcement of judgments of U.S. and U.K. courts in civil and commercial matters (although the United
States and the United Kingdom are both parties to the New York Convention on the Recognition and Enforcement of Foreign Arbitral Awards). Whilst the Hague Convention on the Recognition and Enforcement of Foreign Judgements in Civil or Commercial
Matters came into force in the U.K. on 1 July 2025 and provides for reciprocal enforcement between the U.K. and certain other countries which have ratified the Convention, this does not apply to the U.S. which has only signed, and not yet
ratified, the Convention. Accordingly, a final judgment for the payment of money rendered by any general or state court in the United States based on civil liability, whether or not predicated solely upon the United States securities laws, would not
be automatically recognized and enforceable in England and Wales and would need to be enforced under the English common law regime which applies to final conclusive money judgements only.

We have also been advised by Cooley (UK) LLP that in order to enforce any final and conclusive monetary judgment for a definite sum obtained against us in
United States courts through the courts of England and Wales, proceedings would need to be commenced in the courts of England and Wales as an action for the payment of a contractual debt. However, no retrial of the issues would be necessary,
provided that:

|
• |
|
the relevant U.S. court had jurisdiction over the original proceedings according to English conflicts of laws
principles at the time when proceedings were initiated;
|

|
• |
|
the claimant commenced proceedings in the courts of England and Wales and we were duly served with process;

|

|
• |
|
the U.S. judgment was final and conclusive on the merits in the sense of being final and unalterable in the court
that pronounced it and being for a definite sum of money;
|

|
• |
|
the judgment given by the courts was not in respect of penalties, taxes, fines or similar fiscal or revenue
obligations (or otherwise based on a U.S. law that an English court considers to relate to a penal, revenue or other public law), or for a declaration or injunction;
|

|
• |
|
the judgment was not procured by fraud;
|

|
• |
|
the judgment was not obtained following a breach of a jurisdictional or arbitrational clause, unless with the
agreement of the defendant or the defendant’s subsequent submission to the jurisdiction of the court;
|

|
• |
|
recognition or enforcement of the judgment in England and Wales would not be contrary to public policy or the
Human Rights Act 1998;
|

41

|
• |
|
the proceedings pursuant to which judgment was obtained were not contrary to natural justice;

|

|
• |
|
the U.S. judgment is not for multiple damages and was not arrived at by doubling, trebling or otherwise
multiplying a sum assessed as compensation for the loss or damages sustained and not being otherwise in breach of Section 5 of the U.K. Protection of Trading Interests Act 1980, or is a judgment based on measures designated by the Secretary of
State under Section 1 of that Act;
|

|
• |
|
there is not a prior decision of an English court or the court of another jurisdiction on the issues in question
between the same parties; and
|

|
• |
|
the English enforcement proceedings were commenced within the limitation period.
|

Whether these requirements are met in respect of a judgment based upon the civil liability provisions of the United States securities laws, including whether
the award of monetary damages under such laws would constitute a penalty, is an issue for the court making such decision.
Subject to the foregoing,
investors may be able to enforce in England and Wales judgments in civil and commercial matters that have been obtained from U.S. federal or state courts. Nevertheless, we cannot assure you that those judgments will be recognized or enforceable in
England and Wales.
If an English court gives judgment for the sum payable under a U.S. judgment, the English judgment will be enforceable by methods
generally available for this purpose. These methods generally permit the English court discretion to prescribe the manner of enforcement.
In addition, it
may not be possible to obtain an English judgment or to enforce that judgment if we are or become subject to any insolvency or similar proceedings, or if we have any set-off or counterclaim against the
judgment creditor. Also note that, in any enforcement proceedings, we may raise any counterclaim that could have been brought if the action had been originally brought in England unless the subject of the counterclaim was in issue and denied in the
U.S. proceedings.

42

WHERE YOU CAN FIND ADDITIONAL INFORMATION

This prospectus is part of the registration statement on Form S-3 we filed with the SEC under the Securities Act. We have also filed a related registration
statement on Form F-6 (File No. 333-248217). This prospectus does not contain all of the information set forth in the registration statement and the exhibits to the
registration statement. For further information with respect to us and the securities we are offering under this prospectus, we refer you to the registration statement and the exhibits and schedules filed as a part of the registration statement. You
should rely only on the information contained in this prospectus or incorporated by reference. We have not authorized anyone else to provide you with different information. We are not making an offer of these securities in any state where the offer
is not permitted. You should not assume that the information in this prospectus is accurate as of any date other than the date on the front page of this prospectus, regardless of the time of delivery of this prospectus or any sale of the securities
offered by this prospectus.
We are subject to the information reporting requirements of the Exchange Act. Accordingly, we are required to file reports,
proxy statements and other information with the SEC, including annual reports on Form 10-K, quarterly reports on Form 10-Q, and current reports on Form 8-K. The SEC
maintains a website that contains reports, proxy and information statements and other information regarding issuers that file electronically with the SEC, including us. The address of the SEC website is www.sec.gov .

We maintain a website at www.silence-therapeutics.com . Information found on, or accessible through, our website is not a part of, and is not
incorporated into, this prospectus, and you should not consider it part of this prospectus or part of any prospectus supplement.

43

INCORPORATION BY REFERENCE

The SEC allows us to “incorporate by reference” information into this prospectus, which means that we can disclose important information to you by
referring you to another document filed separately with the SEC. The information incorporated by reference is deemed to be part of this prospectus, and subsequent information that we file with the SEC will automatically update and supersede that
information. Any statement contained in a previously filed document incorporated by reference will be deemed to be modified or superseded for purposes of this prospectus to the extent that a statement contained in this prospectus modifies or
replaces that statement.
This prospectus and any accompanying prospectus supplement incorporate by reference the documents set forth below that have
previously been filed with the SEC:

|
• |
|
our Annual Report on Form 10-K for the fiscal year ended
December 31, 2025, filed with the SEC on March 5, 2026 ;
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|
• |
|
our Definitive Proxy Statement on Schedule 14A, filed with the SEC on April
29, 2026 (excluding those portions that are not incorporated by reference into our Annual Report on Form 10-K for the fiscal year ended December 31, 2025);
|

|
• |
|
our Quarterly Report on Form 10-Q for the quarter ended March
31, 2026 , filed with the SEC on May 7, 2026; and
|

|
• |
|
the description of our ordinary shares and American Depositary Shares contained in our registration statement on Form
8-A (File No. 001-39487), filed with the SEC on September 2, 2020, including any amendments or reports filed for the purpose of updating such description.

|

We also incorporate by reference into this prospectus all documents (other than current reports furnished under Item 2.02 or Item 7.01
of Form 8-K and exhibits filed on such form that are related to such items) that are filed by us with the SEC pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act after the date of this
prospectus but prior to the termination of the offering. These documents include periodic reports, such as Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q
and Current Reports on Form 8-K, as well as proxy statements.
Unless expressly incorporated by reference, nothing
in this prospectus shall be deemed to incorporate by reference information furnished to, but not filed with, the SEC. Copies of all documents incorporated by reference in this prospectus, other than exhibits to those documents unless such exhibits
are specially incorporated by reference in this prospectus, will be provided at no cost to each person, including any beneficial owner, who receives a copy of this prospectus on the written or oral request of that person made to:

Silence Therapeutics plc
12
Hammersmith Grove
London W6 7AP

United Kingdom
Tel: +44 20 3457
6900
Attention: Investor Relations
You may
also access these documents on our website, www.silence-therapeutics.com. The information contained on, or that can be accessed through, our website is not a part of this prospectus. We have included our website address in this prospectus solely as
an inactive textual reference.
You should rely only on information contained in, or incorporated by reference into, this prospectus. We have not
authorized anyone to provide you with information different from that contained in this prospectus or incorporated by reference in this prospectus. We are not making offers to sell the securities in any jurisdiction in which such an offer or
solicitation is not authorized or in which the person making such offer or solicitation is not qualified to do so or to anyone to whom it is unlawful to make such offer or solicitation.

44

Silence Therapeutics plc

$300,000,000
Ordinary
Shares
(including Ordinary Shares Represented by American Depositary Shares)

PROSPECTUS

, 2026

The information in this preliminary prospectus is not complete and may be changed. We may not
sell these securities until the registration statement filed with the Securities and Exchange Commission is effective. This preliminary prospectus is not an offer to sell these securities and it is not soliciting an offer to buy these securities in
any state where the offer or sale is not permitted.

Subject to Completion, dated May 18, 2026
PROSPECTUS

Silence Therapeutics plc

Up to $100,000,000

Ordinary Shares

(including Ordinary Shares Represented by American Depositary Shares)

We have entered into a certain Open Market Sale Agreement SM , or sales agreement, with Jefferies LLC, or
Jefferies, dated May 18, 2026, relating to the sale of American Depositary Shares, or ADSs, each ADS representing three ordinary shares, nominal value £0.05 per share, of Silence Therapeutics plc offered by this prospectus. In accordance
with the terms of the sales agreement, we may offer and sell ADSs having an aggregate offering price of up to $100,000,000 from time to time through Jefferies, acting as our agent.

The ADSs representing our ordinary shares are listed on The Nasdaq Global Market, or Nasdaq, under the symbol “SLN.” On May 15, 2026, the closing
price of the ADSs on The Nasdaq Global Market was $6.10 per ADS.
Sales of the ADSs, if any, under this prospectus may be made in sales deemed to be an
“at the market offering” as defined in Rule 415(a)(4) promulgated under the Securities Act of 1933, as amended, or the Securities Act. Jefferies is not required to sell any specific amount of securities, but will act as our sales agent
using commercially reasonable efforts consistent with its normal trading and sales practices, on mutually agreed terms between Jefferies and us. There is no arrangement for funds to be received in any escrow, trust or similar arrangement.

Jefferies will be entitled to compensation at a commission rate up to three percent (3.0%) of the gross sales price per share sold. See “Plan of
Distribution” beginning on page S-14 for additional information regarding the compensation to be paid to Jefferies. In connection with the sale of the ADSs on our behalf, Jefferies will be deemed to
be an “underwriter” within the meaning of the Securities Act and the compensation of Jefferies will be deemed to be underwriting commissions. We have also agreed to provide indemnification and contribution to the Agent with respect to
certain liabilities, including liabilities under the Securities Act.
We are a “smaller reporting company” under the federal securities laws
and, as such, we have elected to comply with certain reduced public company reporting requirements for this prospectus and for future filings. See the section titled “Prospectus Summary—Implications of Being a Smaller Reporting
Company.”

Investing in these securities involves a high degree of risk. You should review carefully the risks and uncertainties described under the
heading “ Risk Factors ” on page S-4 of this prospectus and under similar headings in the other documents that are incorporated by reference into this prospectus.

None of the Securities and Exchange Commission, any state securities commission, the U.K. Financial Conduct Authority, nor any other foreign securities
commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

Jefferies
The date of
this prospectus is   , 2026.

TABLE OF CONTENTS

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Page |
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ABOUT THIS PROSPECTUS
|
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S-ii |
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TRADEMARKS
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S-iii |
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PROSPECTUS SUMMARY
|
|
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S-1 |
|

THE OFFERING
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S-2 |
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RISK FACTORS
|
|
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S-4 |
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SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS
|
|
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S-8 |
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USE OF PROCEEDS
|
|
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S-10 |
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DIVIDEND POLICY
|
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S-11 |
|

DILUTION
|
|
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S-12 |
|

PLAN OF DISTRIBUTION
|
|
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S-14 |
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MATERIAL TAX CONSIDERATIONS
|
|
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S-16 |
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LEGAL MATTERS
|
|
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S-25 |
|

EXPERTS
|
|
|
S-26 |
|

SERVICE OF PROCESS AND ENFORCEMENT OF LIABILITIES
|
|
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S-27 |
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WHERE YOU CAN FIND ADDITIONAL INFORMATION
|
|
|
S-29 |
|

INCORPORATION BY REFERENCE
|
|
|
S-30 |
|

S-i

ABOUT THIS PROSPECTUS

This prospectus is part of a shelf registration statement on Form S-3 that we filed with the U.S. Securities and Exchange Commission, or the SEC, utilizing a
“shelf” registration process. This prospectus describes the specific terms of this offering of ADSs and also adds to and updates the documents incorporated by reference into this prospectus.

This prospectus and the documents incorporated into this prospectus by reference include important information about us, the securities being offered and
other information you should know before investing in our securities. To the extent there is a conflict between the information contained in this prospectus, on the one hand, and the information contained in any document incorporated by reference
into this prospectus that was filed with the SEC before the date of this prospectus, on the other hand, you should rely on the information in this prospectus. If any statement in one of these documents is inconsistent with a statement in another
document having a later date (for example, a document incorporated by reference in this prospectus), the statement in the document having the later date modifies or supersedes the earlier statement. Any statement so modified or superseded will not
be deemed, except as so modified or superseded, to constitute a part of this prospectus.
You should rely only on the information contained in or
incorporated by reference in this prospectus, the accompanying base prospectus and in any free writing prospectus that we authorized for use in connection with this offering. We have not, and the sales agent has not, authorized anyone to provide you
with different information. If anyone provides you with different or inconsistent information, you should not rely on it. We are not, and the sales agent is not, making an offer to sell these securities in any jurisdiction where the offer or sale is
not permitted. You should assume that the information appearing in this prospectus, the accompanying base prospectus, the documents incorporated by reference in this prospectus and in any free writing prospectus that we have authorized for use in
connection with this offering, is accurate only as of the date of those respective documents. Our business, financial condition, results of operations and prospects may have changed since those dates. You should read this prospectus, the
accompanying base prospectus, the documents incorporated by reference in this prospectus, and any free writing prospectus that we have authorized for use in connection with this offering, in their entirety before making an investment decision.

We further note that the representations, warranties and covenants made by us in any agreement that is filed as an exhibit to any document that is
incorporated by reference in this prospectus were made solely for the benefit of the parties to such agreement, including, in some cases, for the purpose of allocating risk among the parties to such agreements, and should not be deemed to be a
representation, warranty or covenant to you. Moreover, such representations, warranties or covenants were accurate only as of the date when made. Accordingly, such representations, warranties and covenants should not be relied on as accurately
representing the current state of our affairs.
Unless otherwise indicated or the context otherwise requires, all references in this prospectus to the
terms “Silence,” “Silence Therapeutics,” “the Company,” “we,” “us” and “our” refer to Silence Therapeutics plc together with its subsidiaries. In this prospectus, any reference
to any provision of any legislation shall include any amendment, modification, re-enactment or extension thereof. All references to “shares” in this prospectus refer to o

### EX-5.1 - EX-5.1
EX-5.1
3
d120718dex51.htm
EX-5.1

EX-5.1

Exhibit 5.1

Claire Keast-Butler

+44 (0) 20 7556 4211

ckeastbutler@cooley.com
Silence Therapeutics plc

27 Eastcastle Street
London W1W 8DH

United Kingdom
18 May 2026

Ladies and Gentlemen:

Re: |
Silence Therapeutics plc — Registration Statement on Form S-3
— Exhibit 5.1
|

1. |
INTRODUCTION
|

1.1 |
We have acted as English legal advisers to Silence Therapeutics plc, a public limited company incorporated in
England and Wales (the “ Company ”), in connection with the preparation and filing on the date hereof with the U.S. Securities and Exchange Commission (the “ SEC ”) of a registration statement on Form S-3 (the “ Registration Statement ”), including a base prospectus (the “ Base Prospectus ”), which provides that it will be supplemented by one or more prospectus supplements (each
such prospectus supplement, together with the Base Prospectus, a “ Prospectus ”), pursuant to the U.S. Securities Act of 1933, as amended (the “ Securities Act ”). We have taken instructions solely from the Company.

|

1.2 |
The Registration Statement relates to the registration for issue and sale by the Company of ordinary shares of
£0.05 each in the capital of the Company (“ Ordinary Shares ”) including Ordinary Shares represented by American Depositary Shares with each American Depositary Share representing three Ordinary Shares
(“ ADSs ”), in each case to the public in a registered offering or offerings. The Ordinary Shares, including Ordinary Shares represented by ADSs, sold under the Registration Statement are referred to as the
“ Securities ”.
|

1.3 |
The Company may offer and sell up to US$300,000,000 of Securities pursuant to the Registration Statement. The
Registration Statement includes a sales agreement prospectus supplement (the “ Sales Agreement Prospectus ”) to the Base Prospectus relating to the offering, issuance and sale of an amount of Ordinary Shares represented by ADSs with
an aggregate offering price of up to US$100,000,000 (the “ Sales Agreement Shares ”) that may be issued and sold under a sales agreement between the Company and Jefferies LLC dated 18 May 2026 (the “ Sales
Agreement ”). The US$100,000,000 of ADSs that may be offered, issued and sold by the Company under the Sales Agreement Prospectus is included in the $300,000,000 of Securities that may be offered, issued and sold by the Company under the
Base Prospectus.
|

1.4 |
We are rendering this letter at the request of the Company in connection with the Registration Statement.

|

1.5 |
Except as otherwise defined in this letter, capitalised terms used have the respective meanings given to them
in the Registration Statement and headings are for ease of reference only and shall not affect interpretation.
|

1.6 |
All references to legislation in this letter are to the legislation of England unless the contrary is
indicated, and any reference to any provision of any legislation shall include any amendment, modification, re-enactment or extension thereof, as in force on the date of this letter.
|

Cooley (UK) LLP 22
Bishopsgate London EC2N 4BQ UK
t: +44 (0) 20 7583 4055 f: +44 (0) 20 7785 9355 cooley.com

Cooley (UK) LLP is a limited liability partnership and is registered in England and Wales with registered number OC395270. Our registered office
is at the address above. Cooley (UK) LLP is authorised and regulated by the Solicitors Regulation Authority (SRA number 617791). A list of the members of Cooley (UK) LLP and their professional qualifications is open to inspection at its registered
office. The word ‘partner,’ used in relation to Cooley (UK) LLP, refers to a member of Cooley (UK) LLP or an employee or consultant of Cooley (UK) LLP (or any affiliated firm) of equivalent standing.

Page Two

2. |
DOCUMENTS
|

For the purpose of issuing this letter, we have reviewed the following documents only:

2.1 |
a PDF copy of the Registration Statement filed by the Company with the SEC on 18 May 2026;

|

2.2 |
a PDF copy of the executed Sales Agreement;
|

2.3 |
a PDF copy of an executed certificate dated 18 May 2026 signed by the Company’s company secretary
(the “ Secretary ’ s Certificate ”) relating to certain factual matters as at the date of the Secretary’s Certificate and having annexed thereto copies (certified by the Company’s company
secretary as being true, complete, accurate and up-to-date in each case) of the following documents:
|

|
(a) |
a PDF copy of the certificate of incorporation of the Company dated 18 November 1994, a PDF copy of the
certificate of incorporation on change of name of the Company dated 21 June 1999 and a PDF copy of the certificate of incorporation on change of name of the Company dated 26 April 2007;
|

|
(b) |
a PDF copy of the current articles of association of the Company adopted on 26 June 2025 (the
“ Articles ”);
|

|
(c) |
a PDF copy of the executed written resolutions passed by the board of directors of the Company (the
“ Board ” or the “ Directors ”) on 15 May 2026 which resolved to, inter alia , (i) approve the preparation, execution and filing of the Registration Statement, (ii) approve the form of the Sales
Agreement, (iii) authorise the Interim Principal Executive Officer and the Chief Financial Officer to execute and deliver the Sales Agreement on behalf of the Company, (iv) constitute a pricing committee of the Board (the “ Pricing
Committee ”) to approve various matters in connection with the Sales Agreement, and (iv) authorise the issue and sale by the Company of the Sales Agreement Shares for an aggregate offering amount of up to US$100,000,000 in one or more “at-the-market” offerings pursuant to the Sales Agreement, at the price, at the times and upon such other terms as the Board or the Pricing Committee shall approve
(the “ Board Written Resolutions ”);
|

|
(d) |
a PDF copy of the resolutions passed at the annual general meeting of the Company held on 27 April 2023
(the “ 2023 AGM ”) signed by the Company’s then company secretary, at which it was resolved, inter alia , to (i) authorise the Directors to allot shares in the Company and to grant rights to subscribe for or to
convert any security into shares in the Company pursuant to section 551 of the Companies Act 2006, as amended (the “ Companies Act ”) up to a maximum aggregate nominal amount of £5,402,633.25 during the period ending on
26 April 2028 and (ii) empower the Directors pursuant to section 570 of the Companies Act to allot equity securities (as defined in section 560 of the Companies Act) pursuant to the authority referred to in (i) as if section 561(1) of
the Companies Act did not apply to such allotment up to a maximum aggregate nominal amount of £5,402,633.25 during the period ending on 26 April 2028 (the “ Shareholder Resolutions ”).
|

3. |
SEARCHES
|

In addition to examining the documents referred to in paragraph 2 ( Documents ), we have carried out the following searches only:

3.1 |
an online search at Companies House in England and Wales (“ Companies House ”) with respect to
the Company, carried out at 8:51 a.m. (London time) on 18 May 2026 (the “ Companies House Search ”); and
|

3.2 |
an online enquiry of the Central Registry of Winding-up Petitions at
the Insolvency and Companies List in England and Wales (the “ Central Registry ”) with respect to the Company, carried out at 10:05 a.m. (London time) on 18 May 2026 (the “ Central Registry Enquiry ” and,
together with the Companies House Search, the “ Searches ”).
|

Page Three

4. |
OPINIONS
|

Subject to the assumptions set out in paragraph 5 ( Assumptions ), the scope of the opinions set out in paragraph 6 ( Scope of
Opinions ) and the reservations set out in paragraph 7 ( Reservations ), we are of the opinion that as at the date of this letter:

4.1 |
The Ordinary Shares (other than the Sales Agreement Shares), when issued, delivered and paid for as
contemplated in the Registration Statement and any relevant Prospectus, and in accordance with the terms of a duly authorised, executed and delivered purchase, underwriting or similar agreement, will be validly issued, fully paid or credited as
fully paid, and will not be subject to any call for payment of further capital.
|

4.2 |
The Sales Agreement Shares, when issued and paid for in accordance with the Sales Agreement and as provided in
the Sales Agreement Prospectus, will be validly issued, fully paid and will not be subject to any call for payment of further capital.
|

5. |
ASSUMPTIONS
|

In giving the opinions in this letter, we have assumed (without making enquiry or investigation) that:

5.1 |
all signatures, stamps and seals on all documents are genuine. All original documents are complete, authentic
and up-to-date, and all documents submitted to us as a copy (whether by email or otherwise) are complete and accurate and conform to the original documents of which they
are copies and that no amendments (whether oral, in writing or by conduct of the parties) have been made to any of the documents since they were examined by us;
|

5.2 |
where a document is required to be delivered, each party to it has delivered the same without it being subject
to any escrow or similar arrangement;
|

5.3 |
all documents, forms and notices which should have been delivered to Companies House in respect of the Company
have been and will be so delivered;
|

5.4 |
the information revealed by the Searches is true, accurate, complete and up-to-date in all respects, and there is no information which should have been disclosed by the Searches that has not been disclosed for any reason and there has been no alteration in the status or condition
of the Company since the date and time that the Searches were made, and that the results of the Searches will remain true, complete, accurate and up-to-date as at the
date of the Registration Statement and as at each date on which the Company allots or issues Securities (each, a “ Bring-Down Date ”);
|

5.5 |
no notice has been received by the Company which could lead to the Company being struck off the register of
companies under section 1000 of the Companies Act and no such notice shall have been received as at each Bring-Down Date;
|

5.6 |
the Articles remain in full force and effect and no alteration has been made or will be made to the Articles as
at the date of this letter and as at each Bring-Down Date;
|

5.7 |
the Securities (other than the Sales Agreement Shares) will be sold or issued in accordance with a duly
authorised, executed and delivered purchase, underwriting or similar agreement;
|

5.8 |
the Sales Agreement Shares will be sold and issued pursuant to the Sales Agreement;
|

5.9 |
to the extent that the obligations of the Company under the Sales Agreement, any purchase, underwriting or
similar agreement pursuant to which Securities will be sold or issued or any other document to be entered into in connection with any offering of Securities pursuant to the Registration Statement and any relevant Prospectus (each a
“ Relevant Agreement ” and collectively, the “ Relevant Agreements ”) may be dependent upon such matters, each of the parties to such Relevant Agreement:
|

|
(a) |
is duly organised, validly existing and in good standing (where such concept is legally relevant) under the
laws of its jurisdiction of incorporation;
|

Page Four

|
(b) |
is in compliance, generally, with all applicable laws, rules and regulations to which it is subject, its
constitutional documents and any judicial or administrative judgments, awards, injunctions or orders binding upon it or its property;
|

|
(c) |
has the capacity, power and authority to execute, deliver and perform the Relevant Agreements;

|

|
(d) |
is duly qualified to engage in the activities contemplated by the Relevant Agreements and will not be in breach
of any of its respective obligations under any document, contract, instrument or agreement as a result of its entry into and performance of its obligations under the Relevant Agreements;
|

|
(e) |
is authorised under all applicable laws of its jurisdiction and domicile to submit to the jurisdiction of the
relevant courts or arbitral tribunal specified in such Relevant Agreement and has validly submitted to such jurisdiction; and
|

|
(f) |
has validly authorised, executed and delivered all relevant documents,
|

and that each of the foregoing remains the case as at each Bring-Down Date;

5.10 |
each Relevant Agreement (and any other documents referred to therein) constitutes legal, valid and binding
obligations of each of the parties thereto enforceable under all applicable laws and that each of the Relevant Agreements will remain in full force and effect at each Bring-Down Date;
|

5.11 |
there is an absence of fraud or mutual mistake of fact or law or any other arrangements, agreements,
understandings or course of conduct or prior or subsequent dealings amending, rescinding or modifying or suspending any of the terms of any of the Relevant Agreements or which would result in the inclusion of additional terms therein, and that the
parties have acted in accordance with the terms of each of the Relevant Agreements;
|

5.12 |
in relation to the Registration Statement and any relevant Prospectus and the transactions contemplated
thereby, the Directors have acted and will act in the manner required by section 172 of the Companies Act and that each issuance of Securities pursuant to the Registration Statement and any relevant Prospectus will be made in good faith and on bona
fide commercial terms and on arms’ length terms and for the purposes of carrying on the business of the Company;
|

5.13 |
the Company is, and the Company and each party to the Relevant Agreements will at all relevant times remain, in
compliance with all applicable anti-corruption, anti-money laundering, anti-terrorism, sanctions and human rights laws and regulations;
|

5.14 |
the Registration Statement has become effective under the Securities Act and such effectiveness shall not have
been terminated or rescinded prior to each Bring-Down Date, and the Prospectus has been filed with the SEC and an appropriate prospectus supplement with respect to the Securities has been prepared, delivered and filed in compliance with the
Securities Act and the rules and regulations thereunder prior to any issue of Securities;
|

5.15 |
the resolutions set out in the Board Written Resolutions referred to in paragraph 2.3 ( Documents ) were
validly passed as written resolutions of the Board in accordance with the Articles, that all eligible Directors (being all the Directors who would have been entitled to vote on the matter had it been proposed as a resolution at a Directors’
meeting, but excluding any Director whose vote is not to be counted in respect of a particular matter) signed one or more copies of the Board Written Resolutions, that all relevant provisions of the Companies Act and the Articles were complied with
and the Articles were duly observed (including, if applicable, those relating to the declaration of Directors’ interests or the power of interested Directors to vote) and such resolutions were duly adopted, and have not been revoked or varied
and remain in full force and effect;
|

5.16 |
the 2023 AGM was duly convened and held on 27 April 2023 at which all constitutional, statutory and other
formalities were duly observed, a quorum of shareholders was present throughout and the Shareholder Resolutions referred to in paragraph 2.3 ( Documents ) were duly passed and have not been revoked or varied and remain in full force and effect
as at the date of this letter and each Bring-Down Date, and that all filings required to be made with Companies House in connection therewith were made within the relevant time limits as at the date of this letter and each Bring-Down Date;

|

Page Five

5.17 |
the Ordinary Shares contemplated to be offered under the Registration Statement and any relevant Prospectus
will be allotted and issued pursuant to the authority and power granted to the Directors pursuant to section 551 and section 570 of the Companies Act, respectively and as applicable, under the Shareholder Resolutions, and that authority and that
power are and shall remain unutilised to a sufficient extent to enable the allotment and issue of any of the Ordinary Shares contemplated to be issued pursuant to the Registration Statement and any relevant Prospectus, and that the Directors shall
not allot or issue (or purport to allot or issue) any Ordinary Shares and shall not grant rights (or purport to grant rights) to subscribe for any Ordinary Shares, or convert any security into Ordinary Shares, in excess of such authorities or powers
or in breach of any other limitation on their authority or power to allot and issue shares or grant rights to subscribe for, or convert any security into, Ordinary Shares;
|

5.18 |
if any Ordinary Shares are to be allotted and issued after the expiration date of the Shareholder Resolutions
or if the Shareholder Resolutions have been fully utilised at the relevant time, such Ordinary Shares shall be allotted and issued pursuant to an authority and power granted to the Directors pursuant to section 551 and section 570 or 571 of the
Companies Act at a general meeting of the Company duly convened and held at which all constitutional, statutory and other formalities will be duly observed, a quorum of shareholders will be present throughout and the relevant resolutions will have
been duly passed and will not have been revoked or varied and will remain in full force and effect, and that all filings required to be made with Companies House in connection therewith will have been made within the relevant time limits;

|

5.19 |
any issue of Securities shall have been duly approved by the Board in accordance with the Articles and the
requirements of all applicable laws;
|

5.20 |
all Ordinary Shares will be duly allotted by the Board in accordance with the Articles and the requirements of
all applicable laws;
|

5.21 |
no Ordinary Shares will be allotted or issued, or are or shall be committed to be allotted and issued, at a
discount to their nominal value (whether in dollars or equivalent in any other currency);
|

5.22 |
at the time of each allotment and issue of Ordinary Shares, the Company shall have received in full payment for
such shares in an amount of “cash consideration” (as defined in section 583(3) of the Companies Act) equal to the aggregate subscription price for such shares, such amount not being less than the aggregate nominal value for such shares,
and the Company shall have entered the holder or holders thereof in the register of members of the Company showing that all such shares have been fully paid up as to their nominal value and any premium thereon as at the date of each such allotment;

|

5.23 |
the persons authorised and appointed by the Board to execute any of the Relevant Agreements on behalf of the
Company (the “ Authorised Signatories ”) were or will be so appointed and authorised;
|

5.24 |
the persons executing each of the Relevant Agreements on behalf of the Company were or will be the Authorised
Signatories and their authority had not been or will not be revoked;
|

5.25 |
there will be no fact or matter (such as bad faith, coercion, duress, undue influence or a mistake or
misrepresentation before or at the time any agreement or instrument is entered into, a subsequent breach, release, waiver or variation of any right or provision, an entitlement to rectification or circumstances giving rise to an estoppel) which
might affect the allotment and issue of any Securities that may be issued pursuant to the Registration Statement and any relevant Prospectus;
|

5.26 |
the contents of the Secretary’s Certificate were true and not misleading when given and remain true and
not misleading as at the date of this letter and any Bring-Down Date and there is no fact or matter not referred to in the Secretary’s Certificate which would make any of the information in the Secretary’s Certificate inaccurate or
misleading;
|

Page Six

5.27 |
the Company has not taken any corporate or other action and no steps have been taken or legal proceedings have
been started against the Company for the liquidation, winding-up, dissolution, reorganisation or bankruptcy of, or for the appointment of a liquidator, receiver, trustee, administrator, administrative receiver
or similar officer of, the Company or all or any of its assets (or any analogous proceedings in any jurisdiction) and the Company is not unable to pay its debts as they fall due within the meaning of section 123 of the Insolvency Act 1986, as
amended (the “ Insolvency Act ”) or becomes unable to pay its debts within the meaning of that section as a result of any of the transactions contemplated in this letter, is insolvent or has been dissolved or declared bankrupt;

|

5.28 |
all agreements and documents examined by us that are governed by the laws of any jurisdiction other than
England are on the date of this letter legal, valid and binding under the laws by which they are (or are expected to be) governed;
|

5.29 |
there are no provisions of the laws of any jurisdiction outside England that would have any implication for the
opinions which we express in this letter and that, insofar as the laws of any jurisdiction outside England may be relevant to this letter, such laws have been and will be complied with;
|

5.30 |
all statements of fact and representations and warranties as to matters of fact (except as to matters expressly
set out in the opinions given in this letter) contained in or made in connection with any of the documents examined by us were true and correct as at the date given and are true and correct at today’s date and no fact was omitted therefrom
which would have made any of such facts, representations or warranties incorrect or misleading;
|

5.31 |
all consents, licences, approvals, authorisations, notices, filings and registrations that are necessary under
any applicable laws or regulations in connection with the transactions contemplated by the Registration Statement have been or will be duly made or obtained and are, or will be, in full force and effect;
|

5.32 |
we note that the Sales Agreement provides that it is to be governed by and construed in accordance with New
York law. We express no opinion as to any matters governed by New York law. As lawyers not qualified in the State of New York, we are not qualified or able to assess the true meaning or import of the terms of the Sales Agreement under New York law,
and we have made no investigation of such meaning or import. Therefore, our review of the Sales Agreement has been limited to their terms as they appear to us on their face. We have assumed that the choice of New York law in the Sales Agreement is
valid as a matter of New York law and the Sales Agreement and its provisions are valid, binding and enforceable under New York law and the law of any other jurisdiction whose law applies, other than law covered expressly in an opinion included in
this letter. We have also assumed that, under New York law, any court named in the forum selection clauses of the Sales Agreement will have jurisdiction over the parties and the subject matter of any action brought in that court under the Sales
Agreement;
|

5.33 |
except to the extent expressly set out in the opinion given in this letter, no consents, approvals,
authorisations, orders, licences, registrations, filings or similar formalities are required from any governmental or regulatory authority in connection with the execution, delivery and performance of any of the Relevant Agreements by any of the
parties thereto or if such consents, approvals, authorisations, orders, licences, registrations, filings or similar formalities are required, these have been made or will be made within the prescribed time limits;
|

5.34 |
no Securities have been or shall be offered to the public in the United Kingdom in breach of the Financial
Services and Markets Act 2000, as amended (the “ FSMA ”), the Public Offers and Admissions to Trading Regulations 2024 (the “ POATRs ”) and the Financial Conduct Authority’s Prospectus Rules: Admission to
Trading on a Regulated Market sourcebook (the “ PRM ”) or of any other United Kingdom laws or regulations concerning offers of securities to the public and no communication has been or shall be made in relation to the Securities in
breach of section 21 ( Restrictions on financial promotion ) of the FSMA or any other United Kingdom laws or regulations relating to offers or invitations to subscribe for, or to acquire rights to subscribe for or otherwise acquire, shares or
other securities;
|

Page Seven

5.35 |
in issuing Securities, the Company is not carrying on a regulated activity for the purposes of section 19 of
the FSMA;
|

5.36 |
all applicable provisions of the EU Market Abuse Regulation (Regulation (EU) No 596/2014) as it forms part of
domestic law in the United Kingdom by virtue of the Withdrawal Act (“ UK MAR ”), the POATRs, the PRM, the FSMA, the Financial Services Act 2012 (the “ FS Act ”), and all rules and regulations made pursuant to UK
MAR, the POATRs, the PRM, the FSMA and the FS Act, have been and will be complied with as regards anything done in relation to the Securities or otherwise in relation to the Relevant Agreements and the transactions contemplated thereby in, from or
otherwise involving England (including, without limitation, articles 14 ( Prohibition of insider dealing and of unlawful disclosure of inside information ) and 15 ( Prohibition of market manipulation ) of UK MAR, sections 19 ( The
general prohibition ) and 21 ( Restrictions on financial promotion ) of the FSMA and sections 89 ( Misleading statements ), 90 ( Misleading impressions ) and 91 ( Misleading statements etc. in relation to benchmarks ) of the
FS Act);
|

5.37 |
the Company’s place of central management and control is not, and will not be as at each Bring-Down Date,
the UK, the Channel Islands or the Isle of Man for the purposes of the City Code on Takeovers and Mergers; and
|

5.38 |
no application has been or will be made for any Securities to be listed or admitted to trading on a regulated
market, multilateral trading facility or organised trading facility situated or operating in the United Kingdom.
|

6. |
SCOPE OF OPINIONS
|

6.1 |
The opinions given in this letter are limited to English law as it would be applied by English courts on the
date of this letter.
|

6.2 |
We express no opinion in this letter on the laws of any other jurisdiction. We have not investigated the laws
of any country other than England and we assume that no foreign law affects any of the opinions stated in paragraph 4 ( Opinions ).
|

6.3 |
We express no opinion as to any agreement, instrument or other document other than as specified in this letter.
For the purposes of giving the opinions in paragraph 4 ( Opinions ), we have only examined and relied on those documents set out in paragraph 2 ( Documents ) and made those searches and enquiries set out in paragraph 3 ( Searches ),
respectively. We have made no further enquiries concerning the Company or any other matter in connection with the giving of the opinions in paragraph 4 ( Opinions ).
|

6.4 |
No opinion is expressed with respect to taxation in the United Kingdom or otherwise in this letter.

|

6.5 |
We have not been responsible for investigating or verifying the accuracy of the facts or the reasonableness of
any statement of opinion or intention, contained in or relevant to any document referred to in this letter, or that no material facts have been omitted therefrom.
|

6.6 |
The opinions given in this letter are given on the basis of each of the assumptions set out in paragraph 5
( Assumptions ) and are subject to each of the reservations set out in paragraph 7 ( Reservations ) to this letter. The opinions given in this letter are strictly limited to the matters stated in paragraph 4 ( Opinions ) and do not
extend, and should not be read as extending, by implication or otherwise, to any other matters.
|

6.7 |
This letter only applies to those facts and circumstances which exist as at today’s date and we assume no
obligation or responsibility to update or supplement this letter to reflect any facts or circumstances which may subsequently come to our attention, any changes in laws which may occur after today, or to inform the addressee of any change in
circumstances happening after the date of this letter which would alter the opinion given in this letter.
|

Page Eight

6.8 |
We have not been responsible for investigation or verification of statements of fact (including statements as
to foreign law) or the reasonableness of any statements of opinion in the Registration Statement and any relevant Prospectus, or that no material facts have been omitted therefrom.
|

6.9 |
This letter is given by Cooley (UK) LLP and no partner or employee assumes any personal responsibility for it
nor shall owe any duty of care in respect of it.
|

6.10 |
This letter, the opinions given in it, and any non-contractual
obligations arising out of or in connection with this letter and/or the opinions given in it, are governed by and shall be construed in accordance with English law as at the date of this letter.
|

7. |
RESERVATIONS
|

7.1 |
The Companies House Search described at paragraph 3.1 ( Searches ) is not capable of revealing
conclusively whether or not:
|

|
(a) |
a winding-up order has been made or a resolution passed for the winding-up of a company;
|

|
(b) |
an administration order has been made; or
|

|
(c) |
a receiver, administrative receiver, administrator or liquidator has been appointed,
|

since notice of these matters may not be filed with the Registrar of Companies in England and Wales immediately and, when filed, may not be
entered on the public database or recorded on the public microfiches of the relevant company immediately.
In addition, such a company
search is not capable of revealing, prior to the making of the relevant order, whether or not a winding-up petition or a petition for an administration order has been presented.

7.2 |
The Central Registry Enquiry described at paragraph 3.2 ( Searches ) relates only to a compulsory winding-up and is not capable of revealing conclusively whether or not a winding-up petition in respect of a compulsory winding-up has
been presented, since details of the petition may not have been entered on the records of the Central Registry immediately or, in the case of a petition presented to a District Registry and/or County Court in England and Wales, may not have been
notified to the Central Registry and entered on such records at all, and the response to an enquiry only relates to the period since approximately 2016 for petitions presented in London and since approximately 2019 for petitions presented to a
District Registry and/or County Court in England and Wales. We have not made enquiries of any District Registry or County Court in England and Wales.
|

7.3 |
The opinions set out in this letter are subject to: (i) any limitations arising from applicable laws
relating to insolvency, bankruptcy, administration, reorganisation, liquidation, moratoria, schemes or analogous circumstances; and (ii) an English court exercising its discretion under section 426 of the Insolvency Act ( co-operation between courts exercising jurisdiction in relation to insolvency ) to assist the courts having the corresponding jurisdiction in any part of the United Kingdom or any relevant country or territory.

|

7.4 |
We express no opinion as to matters of fact.
|

7.5 |
Save for the matters set out in the Secretary’s Certificate, we have made no enquiries of any individual
connected with the Company. We have relied entirely on the facts, statements and confirmations contained in the Secretary’s Certificate and we have not undertaken any independent investigation or verification of the matters referred to in the
Secretary’s Certificate.
|

7.6 |
The opinion set out in paragraph 4.1 ( Opinions ) relates only to Ordinary Shares offered or sold from
time to time pursuant to the Registration Statement that are new Ordinary Shares issued by the Company from time to time following the date of the Registration Statement. We express no opinion in respect of any securities of the Company existing as
at the date of this opinion which may be offered or sold from time to time.
|

Page Nine

7.7 |
If (a) a party to any of the Relevant Agreements is the target of economic or financial sanctions or other
restrictive measures imposed in any jurisdiction (“ Sanctions ”) or is owned or controlled (directly or indirectly) by or is acting on behalf of or at the direction of or is otherwise connected with a person who is a target of
Sanctions or (b) a party to any of the Relevant Agreements is incorporated or resident in or operating from a country or territory that is a target of Sanctions or (c) the rights or obligations of a party to any of the Relevant Agreements
is otherwise affected by Sanctions, then the rights and obligations of such person under the Relevant Agreement may be void and/or unenforceable.
|

7.8 |
We express no opinion in this letter on the application or potential application of the National Security and
Investment Act 2021 in relation to any of the Relevant Agreements or any transaction contemplated thereby.
|

8. |
DISCLOSURE AND RELIANCE
|

8.1 |
This letter is addressed to you solely for your benefit in connection with the Registration Statement and the
transactions contemplated thereunder. We consent to the filing of this letter as an exhibit to the Registration Statement. In giving such consent, we do not thereby admit that we are in the category of persons whose consent is required under section
7 of the Securities Act or the rules and regulations thereunder.
|

8.2 |
This letter may not be relied upon by you for any other purpose, or furnished to, assigned to, quoted to, or
relied upon by any other person, firm or other entity for any purpose, without our prior written consent, which may be granted or withheld at our sole discretion.
|

Yours faithfully
/s/ Cooley (UK) LLP

Cooley (UK) LLP

### EX-23.1 - EX-23.1
EX-23.1
4
d120718dex231.htm
EX-23.1

EX-23.1

Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We hereby consent to the incorporation by reference in this Registration Statement on Form S-3 of Silence
Therapeutics plc of our report dated March 5, 2026 relating to the financial statements, which appears in Silence Therapeutics plc’s Annual Report on Form 10-K for the year ended December 31, 2025. We also consent to the reference to us under the heading “Experts” in such Registration
Statement.

|

/s/ PricewaterhouseCoopers LLP |

Reading, United Kingdom |

May 18, 2026 |

1

### EX-FILING FEES - EX-FILING FEES
EX-FILING FEES

0001479615 2026-05-15 2026-05-15 0001479615 1 2026-05-15 2026-05-15 0001479615 2 2026-05-15 2026-05-15 iso4217:USD xbrli:pure xbrli:shares

Calculation of Filing Fee Tables
|

S-3
|

Silence Therapeutics plc
|

Table 1: Newly Registered and Carry Forward Securities |
☐Not Applicable |

|

|
Security Type
|
Security Class Title
|
Fee Calculation or Carry Forward Rule
|
Amount Registered
|
Proposed Maximum Offering Price Per Unit
|
Maximum Aggregate Offering Price
|
Fee Rate
|
Amount of Registration Fee
|
Carry Forward Form Type
|
Carry Forward File Number
|
Carry Forward Initial Effective Date
|
Filing Fee Previously Paid in Connection with Unsold Securities to be Carried Forward
|

Newly Registered Securities |

|
|
Equity |
Ordinary Shares, nominal value GBP0.05 per share |
457(o) |
|
|
|
|
|
|
|
|
|

Fees to be Paid |
1 |
Unallocated (Universal) Shelf |
|
457(o) |
|
|
$ 300,000,000.00 |
0.0001381 |
$ 41,430.00 |
|
|
|
|

Fees Previously Paid |
|
|
|
|
|
|
|
|
|
|
|
|
|

Carry Forward Securities |

Carry Forward Securities |
|
|
|
|
|
|
|
|
|
|
|
|
|

|

|

|
Total Offering Amounts:
|

|
$ 300,000,000.00
|

|
$ 41,430.00
|

|

|

|

|

|

|

|
Total Fees Previously Paid:
|

|

|

|
$ 0.00
|

|

|

|

|

|

|

|
Total Fee Offsets:
|

|

|

|
$ 0.00
|

|

|

|

|

|

|

|
Net Fee Due:
|

|

|

|
$ 41,430.00
|

|

|

|

|

Offering Note
|

1
|
(A) These ordinary shares, nominal value GBP0.05 per share, are represented by American Depositary Shares, or ADSs, each of which represents three ordinary shares of the Registrant. ADSs issuable on deposit of the ordinary shares registered hereby have been registered pursuant to a separate registration statement on Form F-6 (File No. 333-248217). (B) There are being registered hereunder such indeterminate number of the securities of ADSs as may be sold by the Registrant from time to time at indeterminate prices, with the maximum aggregate offering price not to exceed $300,000,000. The proposed maximum initial offering price per unit will be determined, from time to time, by the Registrant in connection with the issuance by the Registrant of the securities registered hereunder. The securities registered also include such indeterminate number of ordinary shares represented by ADSs. In addition, pursuant to Rule 416 under the Securities Act of 1933, as amended, or the Securities Act, the ordinary shares represented by ADSs being registered hereunder include such indeterminate number of ordinary shares as may be issuable with respect to the ordinary shares being registered hereunder as a result of stock splits, stock dividends or similar transactions. (C) The proposed maximum aggregate offering price per share will be determined from time to time by the Registrant in connection with the issuance by the Registrant of the securities registered hereunder and is not specified as to each class of security pursuant to Instruction 2.A.iii.b. to the Calculation of Filing Fee Tables and Related Disclosure on Item 16(b) of Form S-3 under the Securities Act. (D) The registration fee is calculated pursuant to Rule 457(o) of the Securities Act based on the maximum aggregate offering price. |

|

Table 2: Fee Offset Claims and Sources |
☑Not Applicable |

|

|
Registrant or Filer Name |
Form or Filing Type |
File Number |
Initial Filing Date |
Filing Date |
Fee Offset Claimed |
Security Type Associated with Fee Offset Claimed |
Security Title Associated with Fee Offset Claimed |
Unsold Securities Associated with Fee Offset Claimed |
Unsold Aggregate Offering Amount Associated with Fee Offset Claimed |
Fee Paid with Fee Offset Source |

Rules 457(b) and 0-11(a)(2) |

Fee Offset Claims |
|
|
|
|
|
|
|
|
|
|
|
|

Fee Offset Sources |
|
|
|
|
|
|
|
|
|
|
|
|

Rule 457(p) |

Fee Offset Claims |
|
|
|
|
|
|
|
|
|
|
|
|

Fee Offset Sources |
|
|
|
|
|
|
|
|
|
|
|
|

Table 3: Combined Prospectuses |
☑Not Applicable |

|
Security Type
|
Security Class Title
|
Amount of Securities Previously Registered
|
Maximum Aggregate Offering Price of Securities Previously Registered
|
Form Type
|
File Number
|
Initial Effective Date
|

|
|
|
|
|
|
|
|