Itaconix : View Circular and Notice of General Meeting – February 2023

Market soundings, as defined MAR, were taken in respect of the Placing with the result that certain persons became aware of inside information, as permitted by MAR. That inside information was set out in the Announcement and in this document and has been disclosed as soon as possible in accordance with paragraph 7 of article 17 of MAR. Therefore, those persons who received information in a market sounding are no longer in possession of inside information relating to the Company and its securities.

Notice convening the General Meeting of the Company to be held at the offices of Fieldfisher LLP, 9th Floor, Riverbank House, 2 Swan Lane, London EC4R 3TT on 22 February 2023 at 11.00 a.m., is set out in Part V of this document.

The accompanying Form of Proxy for use in connection with the General Meeting should be completed by Shareholders and returned as soon as possible but, in any event, so as to be received by Link Group, PXS 1, Central Square, 29 Wellington Street, Leeds LS1 4DL no later than

11.00 a.m. on 20 February 2023 (or, in the case of an adjournment of the General Meeting, not later than 48 hours before the time fixed for the holding of the adjourned meeting) together with any power of attorney or other authority (or a notarially certified copy thereof) under which it is signed. Alternatively, Shareholders who hold their shares in uncertificated form may use the CREST electronic proxy appointment service. In order for a proxy appointment made using the CREST service to be valid, the appropriate CREST message must be properly authenticated and contain

the information required for such instructions as described in the CREST Manual. The message must be transmitted so as to be received by the Company's registrars, Link Group, PXS 1, Central

Square, 29 Wellington Street, Leeds LS1 4DL (ID RA10), by no later than 11.00 a.m. on 20 February 2023.

finnCap Ltd, which is authorised and regulated by the FCA and is a member of the London Stock Exchange, is acting as nominated adviser, sole broker, sole bookrunner and co-lead manager to the Company and no one else in connection with the Placing and Open Offer. finnCap's responsibilities as the Company's nominated adviser, sole bookrunner and co-lead manager are owed solely to the London Stock Exchange and the Company and are not owed to any other person.

Canaccord Genuity Limited, which is authorised and regulated by the FCA and is a member of the London Stock Exchange, is acting as co-lead manager to the Company and no one else in connection with the Placing and Open Offer. Its responsibilities as the Company's co-lead manager are owed solely to the Company and are not owed to any other person.

No representation or warranty, express or implied, is made by finnCap or Canaccord as to any of the contents of this document, for which the Company is responsible (without limiting the statutory rights of any person to whom this document is issued). finnCap and Canaccord have not authorised the contents of, or any part of, this document, and no liability whatsoever is accepted by either of finnCap or Canaccord for the accuracy of information or opinions contained in this document or for the omission of any material information. finnCap and Canaccord will not be offering advice and will not otherwise be responsible for providing customer protections to recipients of this document in respect of the Placing and Open Offer or any acquisition of shares in the Company.

Apart from the responsibilities and liabilities, if any, which may be imposed on each of finnCap or Canaccord by FSMA or the regulatory regime established thereunder, finnCap and Canaccord do not accept responsibility whatsoever for the contents of this document, including its accuracy, completeness or verification or for any other statement made or purported to be made by it, or on its behalf, in connection with the Company or the Placing and Open Offer. finnCap and Canaccord accordingly disclaim all and any liability whether arising in tort, contract or otherwise (save as referred to above) in respect of this document or any such statement.

The distribution of this document and the offer of the Placing Shares, the Subscription Shares and the Open Offer Shares in certain jurisdictions may be restricted by law. Accordingly, this document must not be distributed or published in any jurisdiction except under circumstances that will result in full compliance with any applicable laws and regulations. Persons outside of the UK into whose possession this document comes should inform themselves about and observe any such restrictions.

Neither the Placing Shares nor the Open Offer Shares have been approved or disapproved by the U.S. Securities and Exchange Commission, any state securities commission in the United States or any other United States regulatory authority, nor have the foregoing authorities passed upon or

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endorsed the merits of the Placing or the Open Offer or the accuracy or adequacy of this document. Any representation to the contrary is a criminal offence in the United States.

Until 40 days after Admission, an offer or sale of the Placing Shares or Open Offer Shares within the United States by any dealer (whether or not participating in the Placing or Open Offer) may violate the registration requirements of the US Securities Act if such offer or sale is made otherwise than pursuant to an available exemption from registration under the US Securities Act.

NEITHER THE PLACING SHARES, NOR THE SUBSCRIPTION SHARES, NOR THE OPEN OFFER SHARES HAVE BEEN REGISTERED AND WILL NOT BE REGISTERED UNDER THE US SECURITIES ACT, OR ANY STATE SECURITIES LAWS, AND MAY NOT BE OFFERED OR SOLD WITHIN THE US OR TO, OR FOR THE ACCOUNT OR BENEFIT OF, US PERSONS EXCEPT PURSUANT TO AN EXEMPTION FROM, OR IN A TRANSACTION NOT SUBJECT TO, THE REGISTRATION REQUIREMENTS OF THE US SECURITIES ACT AND SUCH OTHER APPLICABLE STATE SECURITIES LAWS. ACCORDINGLY, THE PLACING SHARES, THE SUBSCRIPTION SHARES AND THE OPEN OFFER SHARES MAY BE OFFERED AND SOLD ONLY (I) OUTSIDE OF THE UNITED STATES IN RELIANCE UPON REGULATION S UNDER THE US SECURITIES ACT IN OFFSHORE TRANSACTIONS OR (II) TO "ACCREDITED INVESTORS" AS DEFINED IN RULE 501(A) OF REGULATION D OF THE US SECURITIES ACT, IN RELIANCE ON AN EXEMPTION FROM, OR A TRANSACTION NOT SUBJECT TO, THE REGISTRATION REQUIREMENTS OF THE US SECURITIES ACT.

The New Ordinary Shares will rank pari passu in all respects with the Existing Ordinary Shares including the right to receive all dividends and other distributions declared made or paid on the Ordinary Share capital of the Company.

THE OPEN OFFER

This document is being sent to all Qualifying Shareholders. The Open Offer closes at 11.00 a.m. on 21 February 2023. If you are a Qualifying Shareholder and wish to apply for Open Offer Shares under the Open Offer you should follow the procedure set out in Part IV of this document and, if you are a Qualifying NonCREST Shareholder, then complete and return the accompanying Application Form together with your appropriate remittance. Qualifying CREST Shareholders will not receive an Application Form, but will receive instead a credit to their appropriate stock accounts in CREST in respect of their Basic Open Offer Entitlements which will be enabled for settlement on 7 February 2023. If you do not wish to participate in the Open Offer then you should not return your Application Form or send a USE instruction through CREST.

Applications under the Open Offer may only be made by the Qualifying Shareholder originally entitled or by a person entitled by virtue of a bona fide market claim arising out of a sale or transfer of Existing Ordinary Shares prior to the date on which the Existing Ordinary Shares were marked "ex-entitlement" by the London Stock Exchange. If the Basic Open Offer Entitlements are for any reason not enabled by 3.00 p.m. on 7 February 2023 or such later time as the Company may decide on 7 February 2023, an Application Form will be sent to each Qualifying CREST Shareholder in substitution for the Basic Open Offer Entitlements credited to its stock account in CREST. Qualifying CREST Shareholders who are CREST Sponsored members should refer to their CREST Sponsors regarding the action to be taken in connection with this document and the Open Offer. Applications for Excess Shares pursuant to the Excess Application Facility may be made by the Qualifying Shareholder provided that their Basic Open Offer Entitlement has been taken up in full and subject to being scaled back in accordance with the provisions of this document.

Holdings of Existing Ordinary Shares in certificated and uncertificated form will be treated as separate holdings for the purpose of calculating entitlements under the Open Offer.

Whether or not you intend to be present at the General Meeting, please complete the Form of Proxy enclosed with this document in accordance with the instructions printed on the Form of Proxy and return it to Link Group, PXS 1, Central Square, 29 Wellington Street, Leeds LS1 4DL (ID RA10) by no later than 11.00 a.m. on 20 February 2023 in order to be valid. Completion and return of the Form of Proxy will not preclude you from attending and voting at the General Meeting should you so wish.

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FORWARD LOOKING STATEMENTS

This document includes forward looking statements (that is, statements other than statements of historical facts), including (without limitation) those regarding the Group's financial position, business strategy, plans and objectives of management for future operations, and any statement preceded or followed by, or including, words such as "target", "believe", "expect", "aim", "intend", "will", "may", "anticipate", "would" or "could", or negatives of such words. Such forward looking statements involve known and unknown risks, uncertainties and other factors beyond the Group's control that could cause the actual results, performance or achievements of the Company to be materially different to future results, performance or achievements expressed or implied by such statements. Such forward looking statements are based on numerous assumptions regarding the Group's present and future business strategies and the environment in which the Group will operate in the future. They speak only as at the date of this document. The Company expressly disclaims any obligation to disseminate any update or revision to any forward looking statement in this document to reflect any change in the Company's expectations or any change in events, conditions or circumstances on which any such statement is based, unless required to do so by applicable law or the AIM Rules.

Copies of this document will be available free of charge from the Company's registered office during normal business hours on each day (excluding Saturday, Sunday and public holidays) from the date hereof until the date of the General Meeting. Copies will also be available from the Company's website at www.itaconix.com.

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CONTENTS

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