MREO Mereo BioPharma Group PLC

As filed with the Securities and Exchange Commission on November 25, 2024

Registration No. 333-   

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Form S-3

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

Mereo BioPharma Group plc

(Exact name of registrant as specified in its charter)

One Cavendish Place, 4^th Floor

London, W1G 0QF United Kingdom

+(44) 333 023 7300

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

Mereo US Holdings Inc.

251 Little Falls Drive

Wilmington, Delaware 19808

+1 302 636 5401

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

Copies to:

David S. Bakst

Mayer Brown LLP

1221 Avenue of the Americas

New York, New York 10020

+1 212 506-2500

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, other than securities offered only in connection with dividend or interest reinvestment plans, 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 on filing with the Securities and Exchange 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, 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.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period to comply with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of 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 of 1933 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.

The information in this preliminary prospectus is not complete and may be changed. These securities may not be sold until the registration statement filed with the Securities and Exchange Commission is effective. This preliminary prospectus is not an offer to sell nor does it seek an offer to buy these securities in any jurisdiction where the offer or sale is not permitted.

Subject to Completion, dated November 25, 2024

PROSPECTUS

Mereo BioPharma Group plc

26,638,972 Ordinary Shares Offered by the Selling Shareholders in the form of American Depositary Shares

This prospectus covers the offer and resale by the selling shareholders identified in this prospectus of up to an aggregate of 26,638,972 of our ordinary shares in the form of American Depositary Shares (“ADSs”), consisting of (i) 20,555,067 ordinary shares underlying convertible loan notes and warrants issuable to Novartis Pharma AG (“Novartis”) under the convertible loan and warrant instruments dated February 10, 2020, as amended on November 24, 2020 and February 10, 2023; (ii) 2,487,816 ordinary shares underlying warrants issuable to Silicon Valley Bank and Kreos Capital V (UK) Limited as lenders under previous loan agreements with them dated August 7, 2017 and September 28, 2018, respectively, as amended on December 15, 2020 that have been fully repaid; (iii) 1,551,699 ordinary shares underlying warrants issuable to the Alpha-1 Project, Inc. (“TAP”) under a warrant instrument dated November 2, 2018, as amended on March 29, 2021 and (iv) 2,044,390 ordinary shares issued to AstraZeneca AB (“AstraZeneca”) in connection with a subscription deed dated October 28, 2017, as amended on May 21, 2021 and November 8, 2024.

We are not selling any ADSs under this prospectus and will not receive any of the proceeds from the sale of the ADSs by the selling shareholders. Each of the selling shareholders may offer and sell their ADSs in public or private transactions, or both. These sales may occur at fixed prices, at market prices prevailing at the time of sale, at prices related to prevailing market prices, or at negotiated prices. See “Plan of Distribution” for more information on how the selling shareholders may conduct sales of their ADSs.

We are paying the cost of registering the ADSs covered by this prospectus as well as various related expenses. The selling shareholders are responsible for all selling commissions, transfer taxes and other costs related to the offer and sale of their ADSs.

Our ADSs, each representing five ordinary shares, are listed on The Nasdaq Capital Market under the symbol “MREO.” On November 21, 2024, the last reported sale price of our ADSs on The Nasdaq Capital Market was $3.68 per ADS.

We are an “emerging growth company” and a “smaller reporting company” under applicable Securities and Exchange Commission rules and are eligible for reduced public company disclosure requirements.

Investing in our ADSs involve significant risks. See “Risk Factors” beginning on page 5 of this prospectus and the documents incorporated by reference in this prospectus concerning factors you should consider before investing in our ADSs.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed on the adequacy or accuracy of this prospectus. Any representation to the contrary is a criminal offense.

The date of this prospectus is    , 2024.

TABLE OF CONTENTS

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ABOUT THIS PROSPECTUS

We urge you to read carefully this prospectus, together with the information incorporated herein by reference as described under the heading “Where You Can Find More Information,” before buying any of our ADSs being offered.

Neither we nor the selling shareholders have authorized anyone to provide you with information other than the information that we have provided or incorporated by reference in this prospectus and your reliance on any unauthorized information or representation is at your own risk. This prospectus may be used only in jurisdictions where offers and sales of our ADSs are permitted. You should assume that the information appearing in this prospectus is accurate only as of the date of this prospectus and that any information we have incorporated by reference is accurate only as of the date of the document incorporated by reference, regardless of the time of delivery of this prospectus, or any sale of our ADSs.

A prospectus supplement may add to, update or change the information contained in this prospectus. You should read both this prospectus and any applicable prospectus supplement together with additional information described below under the heading “Where You Can Find Additional Information; Incorporation by Reference.”

Throughout this prospectus, when we refer to the selling shareholders, we are referring to the selling shareholders identified in this prospectus and, as applicable, its permitted transferees or other successors-in-interest that may be identified in a supplement to this prospectus or, if required, a post-effective amendment to the registration statement of which this prospectus is a part.

Throughout this prospectus, and the documents incorporated by reference, unless otherwise designated, the terms “Mereo,” the “Company,” “we,” “us,” and “our” refer to Mereo BioPharma Group plc and our wholly-owned subsidiaries Mereo BioPharma 1 Limited, Mereo BioPharma 2 Limited, Mereo BioPharma 3 Limited, Mereo BioPharma 4 Limited, Mereo BioPharma 5, Inc., Mereo BioPharma Ireland Limited, Mereo US Holdings Inc. and NAVI Subsidiary, Inc. “Mereo,” the Mereo logo and other trademarks, trade names or service marks of Mereo appearing in this prospectus and the documents incorporated by reference are the property of Mereo.

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CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus and any applicable prospectus supplement or free writing prospectus, including the documents that we incorporate by reference herein and therein, contain “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933, as amended, or the Securities Act, and Section 21E of the Securities Exchange Act of 1934, as amended, or the Exchange Act. In some cases, you can identify these statements by terms such as “anticipate,” “believe,” “could,” “estimate,” “expects,” “intend,” “may,” “plan,” “potential,” “predict,” “project,” “should,” “will,” “would” or the negative of those terms, and similar expressions that convey uncertainty of future events or outcomes. In addition, statements that “we believe” and similar statements reflect our beliefs and opinions on the relevant subject. The forward-looking statements are contained principally in the sections entitled “Business” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations” incorporated by reference from our most recent Annual Report on Form 10-K and most recent Quarterly Report on Form 10-Q. These statements relate to future events or to our future financial performance and involve known and unknown risks, uncertainties and other factors which may cause our actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by the forward-looking statements.

In evaluating such forward-looking statements, you should specifically consider various factors, including the risks outlined under the heading “Risk Factors” contained in this prospectus, any accompanying prospectus supplement and any related free writing prospectus, and in our most recent Annual Report on Form 10-K or our most recent Quarterly Report on Form 10-Q filed with the Securities and Exchange Commission, or SEC. The discussion of risks and uncertainties set forth in those filings is not necessarily a complete or exhaustive list of all risks facing us at any particular point in time. 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. Forward-looking statements represent our estimates and assumptions only as of the date such forward-looking statements are made. You should carefully read this prospectus, any accompanying prospectus supplement and any related free writing prospectus, together with the information incorporated herein or therein by reference, and with the understanding that our actual future results may materially differ from what we expect. We qualify all of our forward-looking statements by these cautionary statements.

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RISK FACTORS

Investment in any securities offered pursuant to this prospectus and any applicable prospectus supplement involves risks. You should carefully consider the risk factors incorporated by reference to our most recent Annual Report on Form 10-K and any subsequent Quarterly Reports on Form 10-Q or Current Reports on Form 8-K, and all other information contained or incorporated by reference into this prospectus, as updated by our subsequent filings under the Exchange Act, and the risk factors and other information contained in the applicable prospectus supplement and any applicable free writing prospectus before acquiring any of such securities. The occurrence of any of these risks might cause you to lose all or part of your investment in the offered securities. The risks so described are not the only risks facing us. Additional risks not presently known to us or that we currently deem immaterial may also impair our business operations. Our business, financial condition and results of operations could be materially adversely affected by any of these risks. The trading price of our securities could decline due to any of these risks, and you may lose all or part of your investment. The discussion of risks includes or refers to forward-looking statements; you should read the explanation of the qualifications and limitations on such forward-looking statements discussed elsewhere in this prospectus.

For more information about our SEC filings, please see “Where You Can Find More Information; Incorporation by Reference.”

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USE OF PROCEEDS

We will not receive any of the proceeds from the sale or other disposition of the ADSs by the selling shareholders pursuant to this prospectus.

The selling shareholders will pay any underwriting discounts and commissions and share transfer taxes incurred by the selling shareholders for brokerage or legal services or any other expenses incurred by the selling shareholders in disposing of ADSs. We will bear all other fees and expenses incurred in effecting the registration of the ADSs of the selling shareholders that are covered by this prospectus, including registration and filing fees, fees and expenses of our counsel and our independent registered public accountants.

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DESCRIPTION OF SHARE CAPITAL AND ARTICLES OF ASSOCIATION

The following is a description of the ordinary shares, par value £0.003 per share, of Mereo BioPharma Group plc (the “Company,” “we” or “us”) which are represented by American Depositary Shares (“ADSs”) with each ADS representing five of our ordinary shares registered under Section 12 of the Exchange Act. This description also summarizes relevant provisions of English law. The following summary does not purport to be complete and is subject to, and is qualified in its entirety by reference to, the applicable provisions of English law and the Company’s articles of association, a copy of which is filed as Exhibit 3.1 to the Annual Report on Form 10-K of the Company for the fiscal year ended December 31, 2023. We encourage you to read the articles and the applicable provisions of English law for additional information.

General

We were incorporated as a private limited company with the legal name Mereo BioPharma Group Limited under the laws of England and Wales on March 10, 2015 with the company number 09481161. On June 3, 2016, we re-registered as a public limited company with the legal name Mereo BioPharma Group plc. Our principal executive offices are located at 4th Floor, One Cavendish Place, London, W1G 0QF, United Kingdom. The principal legislation under which we operate and our ordinary shares are issued is the U.K. Companies Act 2006 (as amended) (the “U.K. Companies Act 2006”).

Share Capital

As of November 20, 2024, our issued share capital was £2,327,184, equivalent to 775,728,034 ordinary shares. The nominal value of our ordinary shares, including ordinary shares in the form of ADSs, is £0.003 per ordinary share. Each issued ordinary share is fully paid.

Registered Shares

We are required by the U.K. Companies Act 2006 to keep a register of our shareholders. Under English law, the ordinary shares are 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 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, Link Asset Services.

Holders of our ADSs will not be treated as 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 our ADSs. For discussion on our ADSs and ADS holder rights see “Description of American Depositary Shares” in this prospectus. Holders of our ADSs have a right to receive the ordinary shares underlying their ADSs as discussed in “Description of American Depositary Shares” in this prospectus.

Under the U.K. Companies Act 2006, we must enter an allotment of ordinary shares in our share register as soon as practicable and in any event within two months of the allotment. We will perform all procedures necessary to update the share register with the number of ordinary shares to be issued to the depositary upon sale of the ADSs, pursuant to a supplemental prospectus. We also are required by the U.K. Companies Act 2006 to register a transfer of ordinary shares (or give the transferee notice of and reasons for refusal as the transferee may reasonably request) 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 such register:

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Pre-emptive Rights

English law generally provides shareholders with pre-emptive rights when new shares are issued for cash; however, it is possible for the articles of association, or shareholders by special resolution, to exclude pre-emptive rights. Such an exclusion of pre-emptive rights may be for a maximum period of up to five years from the date of adoption of the articles of association, if the exclusion is contained in the articles of association, or from the date of the shareholder resolution, if the exclusion is by shareholder resolution. In either case, this exclusion would need to be renewed by our shareholders upon its expiration (i.e., at least every five years).

On May 22, 2023, our shareholders authorized our Board to disapply pre-emptive rights for a period until June 30, 2026 in respect of the allotment of ordinary shares or the grant of rights to subscribe for or convert securities into ordinary shares up to a maximum aggregate nominal amount of £2,494,456.76. The nominal value of our ordinary shares is £0.003 per ordinary share.

As of November 20, 2024, non-preemptive authorization up to a maximum nominal amount of £2,148,129.83 remained available to the Company.

Articles of Association

The following is a description of our Articles as at the date hereof.

Shares and Rights Attaching to Them

Objects

The objects of our Company are unrestricted.

Share Rights

Subject to any special rights attaching to shares already in issue, our shares may be issued with or have attached to them any rights or restrictions as we may resolve by ordinary resolution of the shareholders or, failing such determination, as the board may determine.

Voting Rights

Without prejudice to any special rights, privileges or restrictions as to voting rights attached to any shares forming part of our share capital from time to time, the voting rights attaching to shares are as follows:

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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 demanded. Subject to the provisions of the U.K. Companies Act 2006, a poll may be demanded by:

Restrictions on Voting

No shareholder shall (unless the Directors otherwise determine) be entitled to vote at any general meeting in respect of any share held by him or her unless all sums payable by him or her in respect of that share have been paid.

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 at least 14 days’ notice specifying when and how the payment is to be made) pay at the time or times so specified the amount called on his or her shares.

Dividends

We may, subject to the provisions of the U.K. Companies Act 2006 and our Articles, 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 board may from time to time pay shareholders such interim dividends as appear to the board to be justified by our financial position but, if at any time, our share capital is divided into different classes the board may not pay such interim dividends in respect of those shares which confer on the holders thereof deferred or non-preferential rights with regard to dividends if, at the time of payment, any preferential dividend is in arrears.

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 pro rata 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.

No dividend or other moneys payable by us on or in respect of any share shall bear interest against us unless otherwise provided by the rights attached to the share or the provisions of another agreement between the shareholder and us. Any dividend unclaimed after a period of 12 years from the date such dividend became due for payment shall be forfeited and cease to remain owing.

Dividends may be declared or paid in any currency 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, in relation to the currency of any dividend.

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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 non-cash assets of equivalent value, including shares or other securities in any company.

The directors may, if authorized by an ordinary resolution of shareholders, offer any holders of ordinary shares the right to elect to receive in lieu of a dividend, or part of a dividend, an allotment of ordinary shares credited as fully paid up.

Change of Control

There is no specific provision in our Articles that would have the effect of delaying, deferring, or preventing a change of control.

Distributions on Winding Up

If we are in liquidation, the liquidator may, if authorized by a special resolution of shareholders and any other authority required at law, divide among shareholders (excluding us to the extent we are a shareholder by virtue only of holding treasury shares) in specie or in kind the whole or any part of our assets (whether or not the assets consist of property of one kind or consist of properties of different kinds and the liquidator may for such purpose set such value as the liquidator deems fair upon any one or more class or classes of property and may determine how such division shall be carried out as between the shareholders or different classes of shareholders), or vest the whole or any part of such assets in trustees upon such trusts for the benefit of the shareholders as the liquidator determines (and our liquidation may be closed and we may be dissolved), 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 privileges attached to any class of shares issued may be varied or abrogated only with the consent in writing of the holders of not less than three-fourths 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 shares, subject to the other provisions of the U.K. Companies Act 2006 and the terms of their issue. The U.K. Companies Act 2006 also 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 15% or more 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 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 or any capital redemption reserve or any share premium account in any manner authorized by the U.K. Companies Act 2006. We may redeem or purchase all or any of our shares as described in “—Other U.K. Law Considerations—Purchase of Own Shares.”

Preemption Rights

In certain circumstances, our shareholders may have statutory preemption rights under the U.K. Companies Act 2006 in respect of the allotment of new shares as described in “—Pre-emptive Rights” and “—Differences in Corporate Law—Pre-emptive Rights” in this prospectus.

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Transfer of Shares

Any shareholder holding shares in certificated form may transfer all or any of his or her shares by an instrument of transfer in any usual form or any other form 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.

In the case of uncertificated shares, the directors may take such action as they consider appropriate to achieve a transfer. The Uncertificated Securities Regulations 2001 permit shares to be issued and held in uncertificated form and transferred by means of a computer based system.

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

If the board declines to register a transfer, it must return to the transferee the instrument of transfer together with notice of the refusal, unless the board suspects that the proposed transfer may be fraudulent.

Shareholder Meetings

Annual General Meetings

In accordance with the U.K. Companies Act 2006, 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 whenever and wherever the board sees fit, subject to the requirements of the U.K. Companies Act 2006, as described in “—Differences in Corporate Law—Annual General Meeting” and “—Differences in Corporate Law— Notice of General Meetings” in this prospectus.

Notice of General Meetings

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

Quorum of General Meetings

No business, other than the appointment of the chair of the meeting, shall be transacted at any general meeting unless a quorum is present. Subject to the paragraph below, at least two shareholders present in person or by proxy and entitled to vote shall be a quorum for all purposes.

If and for so long as we are subject to the rules and requirements of a securities exchange and such securities exchange requires us to have a quorum for general meetings then, in addition to the requisite quorum requirement stated in the preceding paragraph, in order for such general meeting to be quorate at least 33 1/3 per cent. of our issued and outstanding ordinary shares (or such other

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amount as may be specified by such rules and requirements) must be present at such general meeting, whether represented in person (including, in the case of a corporate shareholder, by duly authorized representative) or by duly appointed proxy.

Class Meetings

The provisions in the Articles relating to general meetings apply to every separate general meeting of the holders of a class of shares.

Directors

Number of Directors

We may not have less than two directors on the Board and not more than ten. We may, by ordinary resolution of the shareholders, vary the minimum and maximum number of directors from time to time.

Appointment of Directors

Subject to the provisions of the Articles, we may, by ordinary resolution of the shareholders or a decision of the directors, elect any person to be a director, either to fill a casual vacancy or as an addition to the existing board, provided the total number of directors does not exceed the maximum number fixed by or in accordance with the Articles. However, any person that is not a director retiring from the existing board must be recommended by the board or the person must have confirmed in writing to us their willingness to be elected as a director not later than seven days before the general meeting at which the relevant resolution is proposed.

Any director appointed by the board will hold office only until the next following annual general meeting at which they must retire. In addition, all directors must retire at the third annual general meeting following the annual general meeting at which such director was elected or last re-elected. Such directors are eligible for re-election at the annual general meeting at which they retire.

The shareholders may, at the meeting at which a director retires, fill the vacated office by electing a person and in default the retiring director shall, if willing to continue to act, be deemed to have been re-elected, unless at such meeting it is expressly resolved not to fill such vacated office or unless a resolution for the re-election of such director shall have been put to the meeting and lost.

Other U.K. Law Considerations

Mandatory Purchases and Acquisitions

Pursuant to Sections 979 to 991 of the U.K. Companies Act 2006, 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 or she 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 compulsory acquisition of the minority shareholders’ shares 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 compulsory acquisition 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

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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 U.K. Companies Act 2006 must, in general, be the same as the consideration that was available under the takeover offer.

Sell Out

The U.K. Companies Act 2006 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 or her shares if, prior to the expiry of the acceptance period for such offer, (i) the offeror has acquired or unconditionally agreed to acquire not less than 90% in value of the voting shares, and (ii) 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 or her 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 U.K. Companies Act 2006, we are empowered to give notice in writing to any person whom we know or have reasonable cause to believe to be interested in our shares, or to have been so interested at any time during the three years immediately preceding the date on which the notice is issued requiring such persons, within a reasonable time to disclose to us particulars of that person’s interest and (so far as is within his or her knowledge) particulars of any other interest that subsists or subsisted in those shares.

Under our Articles, if a person defaults in supplying us with the required particulars in relation to the shares in question (“default shares”), within the prescribed period, the directors may by notice direct that:

Purchase of Own Shares

Under English law, 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. A limited company may

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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.

Subject to the above, we may purchase our own shares in the manner prescribed below. We may make a market purchase on a “recognized investment exchange” of our own fully paid shares pursuant to an ordinary resolution of shareholders. The resolution authorizing the purchase must:

The Nasdaq Capital Market (“Nasdaq”) is not a “recognized investment exchange” on which we may make market purchases. We may purchase our own fully paid shares otherwise than on a “recognized investment exchange” 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 or she 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 U.K. Companies Act 2006, 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 English law.

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:

City Code on Takeovers and Mergers

Following the cancellation of admission of our ordinary shares to trading on the AIM market of London Stock Exchange plc on December 18, 2020, the U.K. Panel on Takeovers and Mergers (the “Panel”) confirmed to us that the U.K. City Code on Takeovers and Mergers (the “City Code”) will not apply to us, and we and our shareholders will therefore not have the benefit of the protections the City Code affords, including, but not limited to, the requirement that a person who acquires an interest in our ordinary shares carrying 30% or more of our voting rights must make a cash offer to all other shareholders at the highest price paid in the 12 months before the offer was announced.

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Notwithstanding the above, we may become subject to the City Code in the future if any changes to the Board composition result in the majority of the Directors being resident in the United Kingdom, Channel Islands or the Isle of Man.

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, other than withholding tax requirements. There is no limitation imposed by English law or in the Articles on the right of non-residents to hold or vote shares.

Differences in Corporate Law

The applicable provisions of the U.K. Companies Act 2006 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 U.K. Companies Act 2006 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 the respective rights and it is qualified in its entirety by reference to Delaware law and English law.

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DESCRIPTION OF AMERICAN DEPOSITARY SHARES

American Depositary Shares

Citibank, N.A. (“Citibank”) has agreed to act as the depositary for the ADSs. Citibank’s depositary offices are located at 388 Greenwich Street, New York, New York 10013. 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 (“ADRs”). The depositary typically appoints a custodian to safekeep the securities on deposit. In this case, the custodian is Citibank, N.A., London Branch, located at 25 Canada Square, Canary Wharf, London, E14 5LB, United Kingdom.

We have appointed Citibank as depositary pursuant to a deposit agreement. A copy of the deposit agreement is on file with the SEC under cover of a registration statement on Form F-6. A copy of the deposit agreement is available from the SEC’s website (www.sec.gov). Please refer to registration number 333-223890, 333-249338, 333-258824 and 333-279433 when retrieving such copy. “Holder” means the person or persons in whose name an ADS is registered on the register maintained by the depositary for such purpose.

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 will be 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.

Each ADS represents the right to receive, and to exercise the beneficial ownership interests in, five ordinary shares that are on deposit with the depositary and/or custodian. An ADS also represents the right to receive, and to exercise the beneficial interests in, any other property received by the depositary or the custodian on behalf of the owner of the ADS but that has not been distributed to the owners of ADSs because of legal restrictions or practical considerations. We and the depositary may agree to change the ADS-to-ordinary share ratio by amending the deposit agreement. This amendment may give rise to, or change, the depositary fees payable by ADS owners. The custodian, the depositary and their respective nominees will hold all deposited property for the benefit of the holders and beneficial owners of ADSs. The deposited property does not constitute the proprietary assets of the depositary, the custodian or their nominees. Beneficial ownership in the deposited property will under the terms of the deposit agreement be vested in the beneficial owners of the ADSs. The depositary, the custodian and their respective nominees will be the record holders of the deposited property represented by the ADSs for the benefit of the holders and beneficial owners of the corresponding ADSs. A beneficial owner of ADSs may or may not be the holder of ADSs. Beneficial owners of ADSs will be able to receive, and to exercise beneficial ownership interests in, the deposited property only through the registered holders of the ADSs, the registered holders of the ADSs (on behalf of the applicable ADS owners) only through the depositary, and the depositary (on behalf of the owners of the corresponding ADSs) directly, or indirectly, through the custodian or their respective nominees, in each case upon the terms of the deposit agreement.

If you become an owner of ADSs, you will become a party to the deposit agreement and therefore will be bound to its terms and to the terms of any ADR that represents your ADSs. The deposit agreement and the ADR specify our rights and obligations as well as your rights and obligations as owner of ADSs and those of the depositary. As an ADS holder you appoint the depositary to act on your behalf in certain circumstances. The deposit agreement and the ADRs are governed by New York law. However, our obligations to the holders of ordinary shares will continue to be governed by the laws of England and Wales, which may be different from the laws in the United States.

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In addition, applicable laws and regulations may require you to satisfy reporting requirements and obtain regulatory approvals in certain circumstances. You are solely responsible for complying with such reporting requirements and obtaining such approvals. None of the depositary, the custodian, us or any of their or our respective agents or affiliates shall be required to take any actions whatsoever on your behalf to satisfy such reporting requirements or obtain such regulatory approvals under applicable laws and regulations.

The manner in which you own the ADSs (e.g., in a brokerage account vs. as registered holder, or as holder of certificated vs. uncertificated ADSs) may affect your rights and obligations, and the manner in which, and extent to which, the depositary’s services are made available to you. As an owner of ADSs, we will not treat you as one of our shareholders and you will not have direct shareholder rights. The depositary will hold on your behalf the shareholder rights attached to the ordinary shares underlying your ADSs. As an owner of ADSs you will be able to exercise the shareholders rights for the ordinary shares represented by your ADSs through the depositary only to the extent contemplated in the deposit agreement. To exercise any shareholder rights not contemplated in the deposit agreement you will, as an ADS owner, need to arrange for the cancellation of your ADSs and become a direct shareholder.

As an owner of ADSs, you may hold your ADSs either by means of an ADR registered in your name, through a brokerage or safekeeping account, or through an account established by the depositary in your name reflecting the registration of uncertificated ADSs directly on the books of the depositary (commonly referred to as the direct registration system or DRS). The direct registration system reflects the uncertificated (book-entry) registration of ownership of ADSs by the depositary. Under the direct registration system, ownership of ADSs is evidenced by periodic statements issued by the depositary to the holders of the ADSs. The direct registration system includes automated transfers between the depositary and DTC, the central book-entry clearing and settlement system for equity securities in the United States. If you decide to hold your ADSs through your brokerage or safekeeping account, you must rely on the procedures of your broker or bank to assert your rights as ADS owner. Banks and brokers typically hold securities such as the ADSs through clearing and settlement systems such as DTC. The procedures of such clearing and settlement systems may limit your ability to exercise your rights as an owner of ADSs. Please consult with your broker or bank if you have any questions concerning these limitations and procedures. All ADSs held through DTC will be registered in the name of a nominee of DTC.

The registration of the ordinary shares in the name of the depositary or the custodian shall, to the maximum extent permitted by applicable law, vest in the depositary or the custodian the record ownership in the applicable ordinary shares with the beneficial ownership rights and interests in such ordinary shares being at all times vested with the beneficial owners of the ADSs representing the ordinary shares. The depositary or the custodian shall at all times be entitled to exercise the beneficial ownership rights in all deposited property, in each case only on behalf of the holders and beneficial owners of the ADSs representing the deposited property.

Dividends and Other Distributions

Holders generally have the right to receive the distributions we make on the securities deposited with the custodian. A Holder’s receipt of these distributions may be limited, however, by practical considerations and legal limitations. Holders of ADSs will receive such distributions under the terms of the deposit agreement in proportion to the number of ADSs held as of the specified record date, after deduction the applicable fees, taxes, and expenses.

Distributions of Cash

Whenever we make a cash distribution for the securities on deposit with the custodian, we will deposit the funds with the custodian. Upon receipt of confirmation of the deposit of the requisite funds,

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the depositary will arrange for the funds received in a currency other than U.S. dollars to be converted into U.S. dollars and for the distribution of the U.S. dollars to the holders, subject to the laws and regulations of England and Wales.

The conversion into U.S. dollars will take place only if practicable and if the U.S. dollars are transferable to the United States. The depositary will apply the same method for distributing the proceeds of the sale of any property (such as undistributed rights) held by the custodian in respect of securities on deposit.

The distribution of cash will be made net of the fees, expenses, taxes, and governmental charges payable by holders under the terms of the deposit agreement. The depositary will hold any cash amounts it is unable to distribute in a non-interest bearing account for the benefit of the applicable holders and beneficial owners of ADSs until the distribution can be effected or the funds that the depositary holds must be escheated as unclaimed property in accordance with the laws of the relevant states of the United States.

Distributions of Shares

Whenever we make a free distribution of ordinary shares for the securities on deposit with the custodian, we will deposit the applicable number of ordinary shares with the custodian. Upon receipt of confirmation of such deposit, the depositary will either distribute to holders new ADSs representing the ordinary shares deposited or modify the ADS-to-ordinary shares ratio, in which case each ADS a Holder holds will represent rights and interests in the additional ordinary shares so deposited. Only whole new ADSs will be distributed. Fractional entitlements will be sold and the proceeds of such sale will be distributed as in the case of a cash distribution.

The distribution of new ADSs or the modification of the ADS-to-ordinary shares ratio upon a distribution of ordinary shares will be made net of the fees, expenses, taxes, and governmental charges payable by holders under the terms of the deposit agreement. In order to pay such taxes or governmental charges, the depositary may sell all or a portion of the new ordinary shares so distributed.

No such distribution of new ADSs will be made if it would violate a law (e.g., the U.S. securities laws) or if it is not operationally practicable. If the depositary does not distribute new ADSs as described above, it may sell the ordinary shares received upon the terms described in the deposit agreement and will distribute the proceeds of the sale as in the case of a distribution of cash.

Distributions of Rights

Whenever we intend to distribute rights to subscribe for additional ordinary shares, we will give prior notice to the depositary and we will assist the depositary in determining whether it is lawful and reasonably practicable to distribute rights to purchase additional ADSs to holders.

The depositary will establish procedures to distribute rights to purchase additional ADSs to holders and to enable such holders to exercise such rights if it is lawful and reasonably practicable to make the rights available to holders of ADSs, and if we provide all of the documentation contemplated in the deposit agreement (such as opinions to address the lawfulness of the transaction). Holders may have to pay fees, expenses, taxes and other governmental charges to subscribe for the new ADSs upon the exercise of a Holder’s rights. The depositary is not obligated to establish procedures to facilitate the distribution and exercise by holders of rights to subscribe for new ordinary shares other than in the form of ADSs.

The depositary will not distribute the rights to a Holder if:

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Elective Distributions

Whenever we intend to distribute a dividend payable at the election of shareholders either in cash or in additional shares, we will give prior notice thereof to the depositary and will indicate whether we wish the elective distribution to be made available to a Holder. In such case, we will assist the depositary in determining whether such distribution is lawful and reasonably practicable.

The depositary will make the election available to a Holder only if it is reasonably practicable and if we have provided all of the documentation contemplated in the deposit agreement. In such case, the depositary will establish procedures to enable such Holder to elect to receive either cash or additional ADSs, in each case as described in the deposit agreement.

If the election is not made available to a Holder, such Holder will receive either cash or additional ADSs, depending on what a shareholder in England and Wales would receive upon failing to make an election, as more fully described in the deposit agreement.

Other Distributions

Whenever we intend to distribute property other than cash, ordinary shares, or rights to purchase additional ordinary shares, we will notify the depositary in advance and will indicate whether we wish such distribution to be made to a Holder. If so, we will assist the depositary in determining whether such distribution to holders is lawful and reasonably practicable.

If it is reasonably practicable to distribute such property to a Holder and if we provide to the depositary all of the documentation contemplated in the deposit agreement, the depositary will distribute the property to the holders in a manner it deems practicable.

The distribution will be made net of fees, expenses, taxes, and governmental charges payable by holders under the terms of the deposit agreement. In order to pay such taxes and governmental charges, the depositary may sell all or a portion of the property received.

The depositary will not distribute the property to a Holder and will sell the property if:

Redemption

Whenever we decide to redeem any of the securities on deposit with the custodian, we will notify the depositary in advance. If it is practicable and if we provide all of the documentation contemplated in the deposit agreement, the depositary will provide notice of the redemption to the holders.

The custodian will be instructed to surrender the shares being redeemed against payment of the applicable redemption price. The depositary will convert into U.S. dollars upon the terms of the deposit

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agreement the redemption funds received in a currency other than U.S. dollars and will establish procedures to enable holders to receive the net proceeds from the redemption upon surrender of their ADSs to the depositary. A Holder may have to pay fees, expenses, taxes, and other governmental charges upon the redemption of such Holder’s ADSs. If less than all ADSs are being redeemed, the ADSs to be retired will be selected by lot or on a pro rata basis, as the depositary may determine.

Changes Affecting Ordinary Shares

The ordinary shares held on deposit for a Holder’s ADSs may change from time to time. For example, there may be a change in nominal (or par) value, split-up, cancellation, consolidation, or any other reclassification of such ordinary shares or a recapitalization, reorganization, merger, consolidation, or sale of assets of ours.

If any such change were to occur, such Holder’s ADSs would, to the extent permitted by law and the deposit agreement, represent the right to receive the property received or exchanged in respect of the ordinary shares held on deposit. The depositary may in such circumstances deliver new ADSs to a Holder, amend the deposit agreement, the ADRs and the applicable registration statement(s) on Form F-6, call for the exchange of such Holder’s existing ADSs for new ADSs and take any other actions that are appropriate to reflect as to the ADSs the change affecting the Shares. If the depositary may not lawfully distribute such property to a Holder, the depositary may sell such property and distribute the net proceeds to such Holder as in the case of a cash distribution.

Issuance of ADSs upon Deposit of Ordinary Shares

The depositary may create ADSs on a Holder’s behalf if such Holder or such Holder’s broker deposit ordinary shares with the custodian. The depositary will deliver these ADSs to the person a Holder indicates only after such Holder pays any applicable issuance fees and any charges and taxes payable for the transfer of the ordinary shares to the custodian. A Holder’s ability to deposit ordinary shares and receive ADSs may be limited by the legal considerations in the United States and England and Wales applicable at the time of deposit.

The issuance of ADSs may be delayed until the depositary or the custodian receives confirmation that all required approvals have been given and that the ordinary shares have been duly transferred to the custodian. The depositary will only issue ADSs in whole numbers.

When a Holder makes a deposit of ordinary shares, such Holder will be responsible for transferring good and valid title to the depositary. As such, a Holder will be deemed to represent and warrant that:

If any of the representations or warranties is incorrect in any way, we and the depositary may, at such Holder’s cost and expense, take any and all actions necessary to correct the consequences of the misrepresentation.

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Transfer, Combination and Split Up of ADRs

ADR holders will be entitled to transfer, combine, or split up such Holder’s ADRs and the ADSs evidenced thereby. For transfers of ADRs, a Holder will have to surrender the ADRs to be transferred to the depositary and also must:

To have Holder’s ADRs either combined or split up, such Holder must surrender the ADRs in question to the depositary with such Holder’s request to have them combined or split up, and such Holder must pay all applicable fees, charges, and expenses payable by ADR holders, pursuant to the terms of the deposit agreement, upon a combination or split up of ADRs.

Withdrawal of Ordinary Shares Upon Cancellation of ADSs

A Holder will be entitled to present such Holder’s ADSs to the depositary for cancellation and then receive the corresponding number of underlying ordinary shares at the custodian’s offices. A Holder’s ability to withdraw the ordinary shares held in respect of the ADSs may be limited by the legal considerations in the United States and England and Wales applicable at the time of withdrawal. In order to withdraw the ordinary shares represented by a Holder’s ADSs, such Holder will be required to pay to the depositary the fees for cancellation of ADSs and any charges and taxes payable upon the transfer of the ordinary shares.

A Holder assumes the risk for delivery of all funds and securities upon withdrawal. Once canceled, the ADSs will not have any rights under the deposit agreement.

If a Holder holds ADSs registered in such Holder’s name, the depositary may ask such Holder to provide proof of identity and genuineness of any signature and such other documents as the depositary may deem appropriate before it will cancel such Holder’s ADSs. The withdrawal of the ordinary shares represented by such Holder’s ADSs may be delayed until the depositary receives satisfactory evidence of compliance with all applicable laws and regulations. Please keep in mind that the depositary will only accept ADSs for cancellation that represent a whole number of securities on deposit.

Holders will have the right to withdraw the securities represented by their ADSs at any time except for:

The deposit agreement may not be modified to impair a Holder’s right to withdraw the securities represented by such Holder’s ADSs except to comply with mandatory provisions of law.

Voting Rights

Holders generally have the right under the deposit agreement to instruct the depositary to exercise the voting rights for the ordinary shares represented by your ADSs. The voting rights of Holders of ordinary shares are described in “Description of Share Capital—Articles of Association” in this prospectus.

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At our request, the depositary will distribute to Holders any notice of shareholders’ meeting received from us together with information explaining how to instruct the depositary to exercise the voting rights of the securities represented by ADSs.

If the depositary timely receives voting instructions from a Holder of ADSs, it will endeavor to vote the securities (in person or by proxy) represented by the Holder’s ADSs as follows:

Securities for which no voting instructions have been received will not be voted (except as otherwise contemplated in the Deposit Agreement). Please note that the ability of the depositary to carry out voting instructions may be limited by practical and legal limitations and the terms of the securities on deposit. We cannot assure Holders that they will receive voting materials in time to enable such Holders to return voting instructions to the depositary in a timely manner.

Fees and Charges

ADS Holders will be required to pay the following fees under the terms of the deposit agreement:

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ADS Holders will also be responsible to pay certain charges such as:

ADS fees and charges payable upon (i) the issuance of ADSs, and (ii) the cancellation of ADSs are charged to the person to whom the ADSs are issued (in the case of ADS issuances) and to the person whose ADSs are cancelled (in the case of ADS cancellations). In the case of ADSs issued by the depositary into DTC, the ADS issuance and cancellation fees and charges may be deducted from distributions made through DTC, and may be charged to the DTC participant(s) receiving the ADSs being issued or the DTC participant(s) holding the ADSs being cancelled, as the case may be, on behalf of the beneficial owner(s) and will be charged by the DTC participant(s) to the account of the applicable beneficial owner(s) in accordance with the procedures and practices of the DTC participants as in effect at the time. ADS fees and charges in respect of distributions and the ADS service fee are charged to the Holders as of the applicable ADS record date. In the case of distributions of cash, the amount of the applicable ADS fees and charges is deducted from the funds being distributed. In the case of (i) distributions other than cash and (ii) the ADS service fee, Holders as of the ADS record date will be invoiced for the amount of the ADS fees and charges and such ADS fees and charges may be deducted from distributions made to Holders of ADSs. For ADSs held through DTC, the ADS fees and charges for distributions other than cash and the ADS service fee may be deducted from distributions made through DTC, and may be charged to the DTC participants in accordance with the procedures and practices prescribed by DTC and the DTC participants in turn charge the amount of such ADS fees and charges to the beneficial owners for whom they hold ADSs. In the case of (i) registration of ADS transfers, the ADS transfer fee will be payable by the Holders of ADSs whose ADSs are being transferred or by the person to whom the ADSs are transferred, and (ii) conversion of ADSs of one series for ADSs of another series, the ADS conversion fee will be payable by the Holder whose ADSs are converted or by the person to whom the converted ADSs are delivered.

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In the event of refusal to pay the depositary fees, the depositary may, under the terms of the deposit agreement, refuse the requested service until payment is received or may set off the amount of the depositary fees from any distribution to be made to the ADS Holder. Certain of the depositary fees and charges (such as the ADS services fee) may become payable shortly after the closing of the ADS offering. Note that the fees and charges Holders may be required to pay may vary over time and may be changed by us and by the depositary. ADS Holders will receive prior notice of such changes. The depositary may reimburse us for certain expenses incurred by us in respect of the ADR program, by making available a portion of the ADS fees charged in respect of the ADR program or otherwise, upon such terms and conditions as we and the depositary agree from time to time.

Amendments

We may agree with the depositary to modify the deposit agreement at any time without Holders’ consent. We undertake to give Holders 30 days’ prior notice of any modifications that would materially prejudice any of their substantial rights under the deposit agreement. We will not consider to be materially prejudicial to holders’ substantial rights any modifications or supplements that are reasonably necessary for the ADSs to be registered under the Securities Act or to be eligible for book-entry settlement, in each case without imposing or increasing the fees and charges Holders are required to pay. In addition, we may not be able to provide holders with prior notice of any modifications or supplements that are required to accommodate compliance with applicable provisions of law.

Holders will be bound by the modifications to the deposit agreement if they continue to hold their ADSs after the modifications to the deposit agreement become effective. The deposit agreement cannot be amended to prevent Holders from withdrawing the ordinary shares represented by holders’ ADSs (except as permitted by law).

Termination

We have the right to direct the depositary to terminate the deposit agreement. Similarly, the depositary may in certain circumstances on its own initiative terminate the deposit agreement. In either case, the depositary must give notice to the Holders at least 30 days before termination. Until termination, Holders’ rights under the deposit agreement will be unaffected.

After termination, the depositary will continue to collect distributions received (but will not distribute any such property until holders request the cancellation of their ADSs) and may sell the securities held on deposit. After the sale, the depositary will hold the proceeds from such sale and any other funds then held for the holders of ADSs in a non-interest bearing account. At that point, the depositary will have no further obligations to holders other than to account for the funds then held for the holders of ADSs still outstanding (after deduction of applicable fees, taxes and expenses).

In connection with the termination of the deposit agreement, the depositary may, independently and without the need for any action by us, make available to holders of ADSs a means to withdraw the ordinary shares and other deposited securities represented by their ADSs and to direct the deposit of such ordinary shares and other deposited securities into an unsponsored American depositary shares program established by the depositary, upon such terms and conditions as the depositary may deem reasonably appropriate, subject however, in each case, to satisfaction of the applicable registration requirements by the unsponsored American depositary shares program under the Securities Act, and to receipt by the depositary of payment of the applicable fees and charges of, and reimbursement of the applicable expenses incurred by, the depositary.

Books of Depositary

The depositary will maintain ADS holder records at its depositary office. Holders may inspect such records at such office during regular business hours but solely for the purpose of communicating with other holders in the interest of business matters relating to the ADSs and the deposit agreement.

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The depositary will maintain in New York facilities to record and process the issuance, cancellation, combination, split-up, and transfer of ADSs. These facilities may be closed from time to time, to the extent not prohibited by law.

Limitations on Obligations and Liabilities

The deposit agreement limits our obligations and the depositary’s obligations to Holders. Please note the following:

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Taxes

Holders will be responsible for the taxes and other governmental charges payable on the ADSs and the securities represented by the ADSs. We, the depositary and the custodian may deduct from any distribution the taxes and governmental charges payable by holders and may sell any and all property on deposit to pay the taxes and governmental charges payable by holders. Holders will be liable for any deficiency if the sale proceeds do not cover the taxes that are due.

The depositary may refuse to issue ADSs; to deliver, transfer, split, and combine ADRs; or to release securities on deposit until all taxes and charges are paid by the applicable holder. The depositary and the custodian may take reasonable administrative actions to obtain tax refunds and reduced tax withholding for any distributions on your behalf. However, holders may be required to provide to the depositary and to the custodian proof of taxpayer status and residence and such other information as the depositary and the custodian may require to fulfill legal obligations. Holders are required to indemnify us, the depositary and the custodian for any claims with respect to taxes based on any tax benefit obtained for such holders.

Foreign Currency Conversion

The depositary will arrange for the conversion of all foreign currency received into U.S. dollars if such conversion is practical, and it will distribute the U.S. dollars in accordance with the terms of the deposit agreement. Holders may have to pay fees and expenses incurred in converting foreign currency, such as fees and expenses incurred in complying with currency exchange controls and other governmental requirements.

If the conversion of foreign currency is not practical or lawful, or if any required approvals are denied or not obtainable at a reasonable cost or within a reasonable period, the depositary may take the following actions in its discretion:

Governing Law/Waiver of Jury Trial

The deposit agreement and the ADRs will be interpreted in accordance with the laws of the State of New York. The rights of holders of ordinary shares (including ordinary shares represented by ADSs) is governed by the laws of England and Wales.

As an owner of ADSs, you irrevocably agree that any legal action arising out of the Deposit Agreement, the ADSs or the ADRs, involving the Company or the Depositary, may only be instituted in a state or federal court in the city of New York.

AS A PARTY TO THE DEPOSIT AGREEMENT, YOU IRREVOCABLY WAIVE, TO THE FULLEST EXTENT PERMITTED BY APPLICABLE LAW, ANY AND ALL RIGHT TO TRIAL BY JURY IN ANY LEGAL PROCEEDING AGAINST US AND/OR THE DEPOSITARY ARISING OUT OF, OR RELATING TO, THE DEPOSIT AGREEMENT, ANY ADR AND ANY TRANSACTIONS CONTEMPLATED IN THE DEPOSIT AGREEMENT (WHETHER BASED ON CONTRACT, TORT, COMMON LAW OR OTHERWISE).

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SELLING SHAREHOLDERS

This prospectus covers the offer and resale of up to an aggregate of 26,638,972 of our ordinary shares, in the form of ADSs, consisting of (i) 20,555,067 ordinary shares underlying convertible loan notes and warrants issuable to Novartis under the convertible loan and warrant instruments dated February 10, 2020, as amended on November 24, 2020 and February 10, 2023; (ii) 2,487,816 ordinary shares underlying warrants issuable to Silicon Valley Bank and Kreos Capital V (UK) Limited as lenders under previous loan agreements with them dated August 7, 2017 and September 28, 2018, respectively, as amended on December 15, 2020 that have been fully repaid; (iii) 1,551,699 ordinary shares underlying warrants issuable to TAP under a warrant instrument dated November 2, 2018, as amended on March 29, 2021 and (iv) 2,044,390 ordinary shares issued to AstraZeneca in connection with a subscription deed dated October 28, 2017, as amended on May 21, 2021 and November 8, 2024.

The Novartis Loan Note and Warrants

In July 2015, three of our wholly-owned subsidiaries, Mereo BioPharma 3 Limited, Mereo BioPharma 2 Limited, and Mereo BioPharma 1 Limited (the “Subsidiaries”), entered into asset purchase agreements to acquire from Novartis rights to setrusumab, acumapimod, and leflutrozole (the “Compounds”), respectively, and certain related assets (together with the Compounds, the “Novartis Assets”). As part of our relationship with Novartis, we entered into a convertible loan note instrument dated February 10, 2020 with Novartis pursuant to which we issued 3,841,479 unsecured convertible loan notes at an exercise price of £0.265 and interest payable in the form of ordinary shares at 6% per annum for three years for a total of 17,105,453 ordinary shares (equivalent to 3,421,090 ADSs) and also granted Novartis warrants over 1,449,614 ordinary shares (equivalent to 289,922 ADSs) pursuant to the Deed of Consent and Amendment to Note Instrument, dated November 24, 2020 and the Deed of Consent and Amendment to Warrant Instrument, dated November 24, 2020. On February 10, 2023, we entered into a Deed of Consent and Amendment to Note Instrument with Novartis, pursuant to which we and Novartis agreed to extend the maturity of the convertible loan notes by two years, from February 10, 2023 to February 10, 2025, while increasing the interest rate to 9%. Pursuant to the amendment and a new warrant instrument, interest accrued to the amendment date was paid in cash, and warrants to purchase 2,000,000 ordinary shares (equivalent to 400,000 ADSs) at an exercise price of £0.150 per ordinary share were issued. Following this transaction, Novartis has convertible loan notes and warrants over a total of 20,555,067 ordinary shares (equivalent to 4,111,013 ADSs).

Silicon Valley Bank and Kreos Capital Warrants

On August 7, 2017, we entered into a loan agreement, with Silicon Valley Bank and Kreos Capital V (UK) Limited (the “Former Lenders”), which provided for total borrowings of £20.0 million and in connection with the borrowings we issued to the Former Lenders warrants to subscribe for our ordinary shares pursuant to a warrant instrument dated August 21, 2017 (the “2017 Warrant Instrument”) and another warrant instrument on substantively similar terms on October 1, 2018 (the “2018 Warrant Instrument”). The 2017 Warrant Instrument and the 2018 Warrant Instrument are referred to as the “Warrant Instruments.”

Under the Warrant Instruments initial allocations of warrants were issued to the Former Lenders with further issues following adjustment of the warrants from time to time resulting in each of the Former Lenders holding 621,954 warrants with each such warrant being exercisable at a subscription price of £2.95 per ordinary share.

The 2017 Warrant Instrument will be capable of exercise until August 21, 2027 and the 2018 Warrant Instrument will be capable of exercise until October 1, 2028.

On December 15, 2020, we prepaid all amounts due and owing to the Former Lenders and also issued additional warrants giving each of the Former Lenders the right to subscribe for 621,954

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ordinary shares at a price of $0.4144 per ordinary share (the “2020 Warrants”). The 2020 Warrants are an adjustment to the 2017 Warrant Instrument and the 2018 Warrant Instrument and the 2020 Warrants issued to each of the Former Lenders were apportioned between the 2017 Warrant Instrument and 2018 Warrant Instrument in the number of 469,575 and 152,379 respectively for each Former Lender and are subject to the same final exercise date as all prior warrants issued to the Former Lenders being August 21, 2027 for the 2017 Warrant Instrument and October 1, 2028 for the 2018 Warrant Instrument.

Following these transactions, the Former Lenders have warrants to purchase a total of 1,243,908 ordinary shares at an exercise price of £2.95 per ordinary share for the 2017 and 2018 Warrant Instruments and a total of 1,243,908 ordinary shares at an exercise price of $0.4144 per ordinary share for the 2020 Warrants. It is our understanding that, following the effectiveness of SVB Financial Group’s reorganization plan on November 7, 2024, the warrants owned by Silicon Valley Bank were vested in the liquidating trust.

The Alpha-1 Project Inc. Warrants

In October 2018, we entered into a funding agreement with TAP, which provided for total payments of $0.4 million, of which the final installment of $0.1 million was received in May 2023. In exchange for funding, we issued warrants allowing TAP to subscribe for ordinary shares in the Company. Under the agreement, TAP is potentially entitled to receive a payment equivalent to the amounts received by us (up to a maximum of $0.4 million) conditional on and within 30 days of the first regulatory approval for alvelestat.

According to the warrant agreement, dated November 2, 2018, and amended on March 29, 2021, we issued TAP (i) on November 16, 2018 warrants over 41,286 ordinary shares; (ii) on April 21, 2022, warrants over 1,101,683 ordinary shares and (iii) on May 10, 2023, warrants over 408,730 ordinary shares.

AstraZeneca Shares

In October 2017, we entered into an exclusive license and option agreement (the “License Agreement”) and subscription deed, with the subscription deed being amended and restated by an amendment deed in May 2021 (the “Subscription Deed” and, together with the License Agreement, the “Original Agreements”) with AstraZeneca AB (“AstraZeneca”). Each of these were amended on November 8, 2024, when the Company entered into an Amendment and Restatement Agreement related to the License Agreement (the “Amended License Agreement”) and a Deed of Amendment and Restatement related to the Subscription Deed (the “Amended Subscription Deed” and, together with the Amended License Agreement, the “Amended Agreements”).

Under the terms of the Original Agreements, we obtained from AstraZeneca an exclusive worldwide, sub-licensable license under AstraZeneca’s intellectual property rights relating to the product candidate alvelestat, with an option to acquire such intellectual property rights following commencement of a pivotal trial and payment of related milestone payments (the “Option”), together with the acquisition of certain related assets. Upon entering into the Original Agreements, we made a payment of $3.0 million and issued 490,798 ordinary shares (equivalent to 98,159 ADSs) to AstraZeneca, for an aggregate upfront payment equal to $5.0 million. Following execution of the Amended License Agreement, we issued 2,044,390 ordinary shares (equivalent to 408,878 ADSs) and paid $0.5 million to AstraZeneca in respect of an agreed milestone.

Under the terms of the Amended Agreements, we agreed, in connection with certain further development and regulatory milestones, to make potential future payments both in cash and through the issue of a variable number of additional ADSs to AstraZeneca of up to $114.3 million in the aggregate for products included in the Amended License Agreement. The number of ADSs to be

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issued to satisfy equity milestones is determined by dividing a monetary amount by a defined subscription price. In addition, the Company has agreed to make payments to AstraZeneca based on specified commercial milestones of the product. The Company has also agreed to pay a specified percentage of sub-licensing revenue to AstraZeneca and to make royalty payments to AstraZeneca equal to ascending specified percentages of tiered annual worldwide net sales by the Company of licensed products (subject to certain reductions), ranging from the high single digits to low double digits. Royalties will be payable on a licensed-product-by-licensed-product and country-by-country basis until the later of ten years after the first commercial sale of such licensed product in such country and expiration of the last patent covering such licensed product in such country that would be sufficient to prevent generic entry. We have agreed to use commercially reasonable efforts to develop and commercialize at least one licensed product.

The Amended License Agreement will expire on the expiration of the last-to-expire royalty term with respect to all licensed products. Upon the expiration of the royalty term for a licensed product in a particular country, the licenses to the Company for such product in such country will become fully paid and irrevocable. Prior to exercise of the Option, if at all, the Company may terminate the Amended License Agreement upon prior written notice. Either party may terminate the agreement upon prior written notice for the other party’s material breach that remains uncured for a specified period of time or insolvency.

The selling shareholders may sell all, some or none of their Resale Shares included in this prospectus. See “Plan of Distribution.” In the table below, the percentage of shares beneficially owned is based on 775,728,034 of our ordinary shares outstanding as of November 20, 2024, determined in accordance with Rule 13d-3 under the Exchange Act of 1934, as amended. Under such rule, beneficial ownership includes any shares over which the selling shareholders has sole or shared voting power or investment power and also any shares that the selling shareholders has the right to acquire within 60 days of such date through the exercise of any options or other rights.

To our knowledge, except as may be disclosed herein, none of the selling shareholders have, and within the past three years have not had, any position, office or other material relationship with us or any of our affiliates, other than the right to appoint a director and/or an observer to our board of directors and the beneficial ownership of our ordinary shares. To our knowledge, none of the selling shareholders is a broker-dealer, nor at the time of the acquisition of our ordinary shares did any of the selling shareholders have direct or indirect agreements or understandings with any person to distribute any of our ordinary shares.

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PLAN OF DISTRIBUTION

The registration statement of which this prospectus forms a part has been filed in part in respect of, an aggregate of 26,638,972 ordinary shares (including those issuable upon the exercise of warrants or conversion of convertible loan notes), in the form of ADSs, consisting of (i) 20,555,067 ordinary shares underlying convertible loan notes and warrants issuable to Novartis under the convertible loan and warrant instruments dated February 10, 2020, as amended on November 24, 2020 and February 10, 2023; (ii) 2,487,816 ordinary shares underlying warrants issuable to Silicon Valley Bank and Kreos Capital V (UK) Limited as lenders under previous loan agreements with them dated August 7, 2017 and September 28, 2018, respectively, as amended on December 15, 2020 that have been fully repaid; (iii) 1,551,699 ordinary shares underlying warrants issuable to TAP under a warrant instrument dated November 2, 2018, as amended on March 29, 2021 and (iv) 2,044,390 ordinary shares issued to AstraZeneca in connection with a subscription deed dated October 28, 2017, as amended on May 21, 2021 and November 8, 2024. The holders of such ordinary shares are identified in this prospectus as selling shareholders. Any ordinary shares offered and sold in the United States by the selling shareholders will be in the form of ADSs. The selling shareholders are also permitted to sell ordinary shares not represented by ADSs in private or offshore transactions, which resales are not covered by this prospectus. The Selling Shareholders may, or may not, elect to sell their ordinary shares represented by ADSs as and to the extent that each may individually determine. Such sales, if any, will be made through brokerage transactions on Nasdaq or other securities exchange in the United States at prevailing market prices.

The selling shareholders may dispose of all or a portion of their ordinary shares in the form of ADSs from time to time directly or through one or more underwriters, broker-dealers or agents. If ADSs representing our ordinary shares are sold through underwriters or broker-dealers, the selling shareholders will be responsible for any applicable underwriting discounts or commissions or agent’s commissions. ADSs representing our ordinary shares may be sold on Nasdaq or any other national securities exchange or quotation service on which the securities may be listed or quoted at the time of disposition, in the over-the-counter market or in transactions otherwise than on these exchanges or systems or in the over-the-counter market and in one or more transactions at fixed prices, at prevailing market prices at the time of the disposition, at varying prices determined at the time of disposition, or at negotiated prices. These dispositions may be effected in transactions, which may involve crosses or block transactions. The selling shareholders may use any one or more of the following methods when disposing of their ADSs:

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The selling shareholders also may resell all or a portion of their ordinary shares in offshore transactions or open market transactions in reliance upon Regulation S under the Securities Act, if available, rather than under this prospectus, provided that they meet the criteria and conform to the requirements of those provisions.

Broker-dealers engaged by the selling shareholders may arrange for other broker-dealers to participate in dispositions. If the selling shareholders effects such transactions by selling ADSs representing our ordinary shares to or through underwriters, broker-dealers or agents, such underwriters, broker-dealers or agents may receive applicable commissions in the form of discounts, concessions or commissions from the selling shareholders or commissions from purchasers of ADSs representing our ordinary shares for whom they may act as agent or to whom they may sell as principal. Such commissions, which shall be payable by the selling shareholders, will be in amounts to be negotiated, but, except as set forth in a supplement to this prospectus, in the case of an agency transaction will not be in excess of a customary brokerage commission in compliance with applicable FINRA rules and regulations.

In connection with dispositions of ADSs representing their ordinary shares, the selling shareholders may enter into hedging transactions with broker-dealers or other financial institutions, which may in turn engage in short sales of ADSs representing their ordinary shares in the course of hedging in positions they assume. The selling shareholders may also sell ADSs representing their ordinary shares short and, if such short sale shall take place after the date that the registration statement of which this prospectus forms a part is declared effective by the Securities and Exchange Commission, the selling shareholders may deliver ADSs representing such shares to close out short positions and to return borrowed shares in connection with such short sales. The selling shareholders may also loan or pledge ADSs representing their ordinary shares to broker-dealers that in turn may sell such shares, to the extent permitted by applicable law. The Selling Shareholders may also enter into option or other transactions with broker-dealers or other financial institutions or the creation of one or more derivative securities which require the delivery to such broker-dealer or other financial institution of ADSs, which ADSs such broker-dealer or other financial institution may resell pursuant to this prospectus (as supplemented or amended to reflect such transaction). Notwithstanding the foregoing, the selling shareholders have been advised that it may not use their ADSs to cover short sales of our ADSs made prior to the date the registration statement of which this prospectus forms a part has been declared effective by the SEC.

The selling shareholders and any broker-dealer or agents participating in the distribution of the ADSs representing their ordinary shares may be deemed to be “underwriters” within the meaning of Section 2(a)(11) of the Securities Act in connection with such dispositions. In such event, any commissions paid, or any discounts or concessions allowed to, any such broker-dealer or agent and any profit on the resale of the ADSs representing our ordinary shares purchased by them may be deemed to be underwriting commissions or discounts under the Securities Act. If the selling shareholders are “underwriters” within the meaning of Section 2(a)(11) of the Securities Act they will be subject to the applicable prospectus delivery requirements of the Securities Act including Rule 172 thereunder and may be subject to certain statutory liabilities thereof, including but not limited to, Sections 11, 12 and 17 of the Securities Act and Rule 10b-5 under the Securities Exchange Act of 1934, as amended, or the Exchange Act.

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LEGAL MATTERS

Mayer Brown LLP will pass upon certain legal matters relating to the issuance and sale of the securities offered hereby on behalf of the Mereo BioPharma Group plc. The validity of the ordinary shares underlying the ADSs to be offered pursuant to this prospectus will be passed upon for us by Latham & Watkins (London) LLP.

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EXPERTS

The financial statements incorporated in this prospectus by reference to the Annual Report on Form 10-K for the year ended December 31, 2023 have been so incorporated in reliance on the report of PricewaterhouseCoopers LLP, an independent registered public accounting firm, given on the authority of said firm as experts in auditing and accounting.

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WHERE YOU CAN FIND MORE INFORMATION; INCORPORATION BY REFERENCE

Available Information

We file reports, proxy statements and other information with the SEC. The SEC maintains a web site that contains reports, proxy and information statements and other information about issuers, such as us, who file electronically with the SEC. The address of that website is http://www.sec.gov.

Our web site address is www.mereobiopharma.com. The information on our web site, however, is not, and should not be deemed to be, a part of this prospectus.

This prospectus and any prospectus supplement are part of a registration statement that we filed with the SEC and do not contain all of the information in the registration statement. The full registration statement may be obtained from the SEC or us, as provided below.

You should review the information and exhibits in the registration statement for further information about us and our consolidated subsidiaries and the securities we are offering. Statements in this prospectus concerning any document we filed as an exhibit to the registration statement or that we otherwise filed with the SEC are not intended to be comprehensive and are qualified by reference to these filings. You should review the complete document to evaluate these statements.

Incorporation by Reference

The SEC’s rules allow 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 this prospectus or 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 or a subsequently filed document incorporated by reference 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:

All reports and other documents we subsequently file pursuant to Section 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934, as amended, which we refer to as the “Exchange Act” in this prospectus, prior to the termination of this offering, including all such documents we may file with the SEC after the date of the initial registration statement and prior to the effectiveness of the registration statement, but excluding any information furnished to, rather than filed with, the SEC, will also be

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incorporated by reference into this prospectus and deemed to be part of this prospectus from the date of the filing of such reports and documents.

You may request a free copy of any of the documents incorporated by reference in this prospectus by writing or telephoning us at:

Mereo BioPharma Group plc

One Cavendish Place, 4^th Floor

London, W1G 0QF

United Kingdom

+44 333 023 7300

Exhibits to the filings will not be sent, however, unless those exhibits have specifically been incorporated by reference in this prospectus or any accompanying prospectus supplement.

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PART II

INFORMATION NOT REQUIRED IN PROSPECTUS

Item 14. Other Expenses of Issuance and Distribution

The following is an estimate, other than with respect to the SEC registration fee, of the expenses (all of which are to be paid by the registrant) that we may incur in connection with the securities being registered hereby.

Item 15. Indemnification of Directors and Officers

The Articles of Association of Mereo BioPharma Group plc (“Mereo,” the “Company” or the “registrant”) provide that Mereo may indemnify the directors and other officers of Mereo in respect of any proceedings, whether civil or criminal, brought against them by reason of their being directors or officers of Mereo and to the fullest extent permitted by the Companies Act 2006 of the United Kingdom (“CA 2006”).

Generally, under CA 2006, any provision by which Mereo directly or indirectly provides an indemnity (to any extent) for a director of Mereo or of an “associated company” (i.e., a company that is a parent, subsidiary or sister company of Mereo) 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 (subject to certain exceptions specified under CA 2006) void.

Mereo has entered into a deed of indemnity with each of its directors. Except as prohibited by applicable law, these deeds of indemnity may require Mereo, among other requirements, to indemnify its directors and executive officers for certain expenses, including attorneys’ fees, costs and expenses incurred by such directors and executive officers with the prior written consent of Mereo in any action or proceeding arising out of their service as a director or executive officer of Mereo, or one of its subsidiaries.

Mereo maintains directors’ and officers’ insurance coverage, which, subject to policy terms and limitations, is expected to include coverage to reimburse Mereo for amounts that it may be required or permitted by law to pay directors or officers of Mereo.

Insofar as indemnification for liabilities arising under the Securities Act of 1933, as amended (the “Securities Act”), may be permitted to directors, officers or persons controlling Mereo pursuant to the foregoing provisions, Mereo has been informed that in the opinion of the Securities and Exchange Commission such indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable.

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Item 16. Exhibits

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Item 17. Undertakings

(a) The undersigned registrant hereby undertakes:

(1) To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement:

(i) To include any prospectus required by Section 10(a)(3) of the Securities Act of 1933;

(ii) To reflect in the prospectus any facts or events arising after the effective date of the registration statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the registration statement. Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the Commission pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than 20 percent change in the maximum aggregate offering price set forth in the “Calculation of Registration Fee” table in the effective registration statement; and

(iii) To include any material information with respect to the plan of distribution not previously disclosed in the registration statement or any material change to such information in the registration statement; provided, however, that paragraphs (a)(1)(i), (a)(1)(ii), and (a)(1)(iii) above do not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in reports filed with or furnished to the SEC by the registrant pursuant to section 13 or section 15(d) of the Securities Exchange Act of 1934 that are incorporated by reference in the registration statement, or is contained in a form of prospectus filed pursuant to Rule 424(b) that is a part of the registration statement.

(2) That, for the purpose of determining any liability under the Securities Act of 1933, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

(3) To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.

(4) That, for the purpose of determining liability under the Securities Act of 1933 to any purchaser:

(A) Each prospectus filed by the registrant pursuant to Rule 424(b)(3) shall be deemed to be part of the registration statement as of the date the filed prospectus was deemed part of and included in the registration statement; and

(B) Each prospectus required to be filed pursuant to Rule 424(b)(2), (b)(5), or (b)(7) as part of a registration statement in reliance on Rule 430B relating to an offering made pursuant to Rule 415(a)(1)(i), (vii), or (x) for the purpose of providing the information required by section 10(a) of the Securities Act of 1933 shall be deemed to be part of and included in the registration statement as of the earlier of the date such form of prospectus is first used after effectiveness or the date of the first contract of sale of securities in the offering described in the prospectus. As provided in Rule 430B, for liability purposes of the issuer and any person that is at that date an underwriter, such date shall be deemed to be a new effective date of the registration statement relating to the securities in the registration statement to which that prospectus relates, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof. Provided, however, that no statement made in a registration statement or prospectus that is part of the registration statement or made in a document incorporated or deemed incorporated by reference into the registration statement or prospectus that is part of the registration statement will, as to a purchaser with a time

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of contract of sale prior to such effective date, supersede or modify any statement that was made in the registration statement or prospectus that was part of the registration statement or made in any such document immediately prior to such effective date.

(b) The undersigned registrant hereby undertakes that, for purposes of determining any liability under the Securities Act of 1933, each filing of the registrant’s annual report pursuant to Section 13(a) or Section 15(d) of the Securities Exchange Act of 1934 (and, where applicable, each filing of an employee benefit plan’s annual report pursuant to Section 15(d) of the Securities Exchange Act of 1934) that is incorporated by reference in the registration statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

(c) Insofar as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to directors, officers and controlling persons of the registrant pursuant to the foregoing provisions, or otherwise, the registrant has been advised that in the opinion of the Securities and Exchange Commission such indemnification is against public policy as expressed in the Securities Act of 1933 and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the registrant of expenses incurred or paid by a director, officer or controlling person of the registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act of 1933 and will be governed by the final adjudication of such issue.

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, as amended, the registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-3 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in London, the United Kingdom, on November 25, 2024.

POWER OF ATTORNEY

KNOW ALL PERSONS BY THESE PRESENT, that each person whose signature appears below hereby constitutes and appoints Denise Scots- Knight, Ph.D. and Christine Fox, and each of them, as his or her true and lawful attorney-in-fact and agent, with full power of substitution and resubstitution, for him or her and in his or her name, place and stead in any and all capacities, in connection with this registration statement, including to sign in the name and on behalf of the undersigned, this registration statement and any and all amendments thereto (and any additional registration statement related hereto permitted by Rule 462(b) promulgated under the Securities Act of 1933, as amended (and all further amendments, including post-effective amendments, thereto)), and to file the same, with all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, granting unto such attorney-in-fact and agent full power and authority to do and perform each and every act and thing requisite and necessary to be done in and about the premises, as fully to all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that said attorney-in-fact and agent, or his or her substitute, may lawfully do or cause to be done by virtue hereof.

Pursuant to the requirements of the Securities Act of 1933, as amended, this registration statement has been signed by the following persons on November 25, 2024 in the capacities indicated.

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SIGNATURE OF AUTHORIZED U.S. REPRESENTATIVE OF REGISTRANT

Pursuant to the requirements of the Securities Act of 1933, as amended, the undersigned, the duly authorized representative in the United States of Mereo BioPharma Group plc, has signed this registration statement on Form S-3 on November 25, 2024.

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Exhibit 5.1

Mereo BioPharma Group plc

4^th Floor

One Cavendish Place

London W1G 0QF

United Kingdom

We have acted as English legal advisers to the Company, a public limited company incorporated in England and Wales in connection with the preparation and filing of a registration statement on Form S-3 to which this opinion letter is attached as an exhibit (such registration statement, as amended, including the documents incorporated by reference therein, the “Registration Statement”), filed with the United States Securities and Exchange Commission (the “SEC”), pursuant to the United States Securities Act of 1933, as amended (the “Securities Act”), on 25 November 2024.

The Registration Statement has been filed in connection with the registration for the offer and resale by certain selling shareholders of the Company, as set forth in the Registration Statement (the “Selling Shareholders”), from time to time of up to 26,638,972 ordinary shares in the capital of the Company with a nominal value of £0.003 per share (“Ordinary Shares”) in the form of American Depositary Shares, each representing five (5) Ordinary Shares (“ADSs”).

In connection with the Registration Statement, we have been asked to provide an opinion on certain matters, as set out below. We have taken instructions in this regard solely from the Company.

In this letter:

Latham & Watkins is the business name of Latham & Watkins (London) LLP, a registered limited liability partnership organised under the laws of New York and authorised and regulated by the Solicitors Regulation Authority (SRA No. 203820). A list of the names of the partners of Latham & Watkins (London) LLP is open to inspection at its principal place of business, 99 Bishopsgate, London EC2M 3XF, and such persons are either solicitors, registered foreign lawyers, or managers authorised by the SRA. We are affiliated with the firm Latham & Watkins LLP, a limited liability partnership organised under the laws of Delaware.

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For the purpose of issuing this letter, we have examined such matters of fact and questions of law as we have considered appropriate. We have reviewed only the following documents and conducted only the following enquiries and searches:

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This letter, the opinion given in it, and any non-contractual obligations arising out of or in connection with this letter and/or the opinion given in it, are governed by, and shall be construed in accordance with, English law, and relate only to English law as applied by the English courts as at today’s date. In particular:

The opinion given in this letter is given on the basis of each of the assumptions set out in Schedule 1 (Assumptions) and is subject to each of the reservations set out in Schedule 2 (Reservations) to this letter. The opinion given in this letter is strictly limited to the matters stated in paragraph 2 (Opinion) below and does not extend, and should not be read as extending, by implication or otherwise, to any other matters.

Based on the documents referred to in paragraph 1 (Introduction) and subject to the other matters set out in this letter and its Schedules and to any matters not disclosed to us, it is our opinion that, as of today’s date:

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the Underlying Shares, if and when allotted and issued, registered in the name of the recipient in the register of members of the Company and delivered in accordance with the terms of the Registration Statement and the relevant Instrument, and as described therein, will be duly and validly authorised and issued, fully paid or credited as fully paid (subject to the receipt of valid consideration by the Company for the issue thereof) and will not be subject to any call for payment of further capital.

We express no opinion as to any agreement, instrument or other document other than as specified in this letter or as to any liability to tax which may arise or be suffered as a result of or in connection with the transactions contemplated by the Registration Statement.

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 our opinion.

This letter is addressed to you solely for your benefit in connection with the Registration Statement. 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.

This letter may not be relied upon by you for any other purpose, and, other than as set out in this paragraph 4, may not be furnished to, or assigned to or relied upon by, any other person, firm or entity for any purpose (including, without limitation, by any person, firm or other entity that acquires Shares from the Company), without our prior written consent, which may be granted or withheld in our discretion.

Sincerely

/s/ LATHAM & WATKINS

LATHAM & WATKINS

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SCHEDULE 1

ASSUMPTIONS

The opinion in this letter has been given on the basis of the following assumptions:

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7

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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 and will not become unable to pay its debts within the meaning of that section as a result of any of the transactions contemplated herein, is not insolvent and has not been dissolved or declared bankrupt (although the Searches gave no indication that any winding-up, dissolution, moratorium or administration order, application or filing or appointment of a liquidator, receiver, administrator, administrative receiver, monitor or similar officer has been made with respect to the Company) and such actions and steps will not have been taken as at any Allotment Date.

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SCHEDULE 2

RESERVATIONS

The opinion in this letter is subject to the following reservations:

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Exhibit 23.3

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We hereby consent to the incorporation by reference in this Registration Statement on Form S-3 of Mereo BioPharma Group plc of our report dated March 27, 2024 relating to the financial statements, which appears in Mereo BioPharma Group plc’s Annual Report on Form 10-K for the year ended December 31, 2023. We also consent to the reference to us under the heading “Experts” in such Registration Statement.

/s/PricewaterhouseCoopers LLP

Reading, United Kingdom

November 25, 2024

Exhibit 107

Calculation of Filing Fee Tables

Form S-3

(Form Type)

Mereo BioPharma Group plc

(Exact Name of Registrant as Specified in its Charter)

Table 1: Newly Registered and Carry Forward Securities