Synthomer : Form of Proxy - AGM 2024

Please detach this portion before posting this proxy form.

Attendance Card

Please bring this card with you to the Meeting and present it at Shareholder registration/accreditation.

The Chair of Synthomer plc invites you to attend the Annual General Meeting of the Company to be held at the offices of the Company, 45 Pall Mall, London SW1Y 5JG on 9 May 2024 at 11.00 am.

Shareholder Reference Number

Form of Proxy - Annual General Meeting to be held on 9 May 2024

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You will be asked to enter the Control Number, Shareholder Reference Number (SRN) and PIN shown opposite and agree to certain terms and conditions.

View the Annual Report online:www.synthomer.com

Control Number: 919023

SRN:

PIN:

Register atwww.investorcentre.co.uk- elect for electronic communications & manage your shareholding online!

To be effective, all proxy appointments must be lodged with the Company's Registrars at: Computershare Investor Services PLC, The Pavilions, Bridgwater Road, Bristol BS99 6ZY by 7 May 2024 at 11.00 am.

Explanatory Notes:

• 1. Every holder has the right to appoint some other person(s) of their choice, who need not be a shareholder, as his or her proxy to exercise all or any of his or her rights, to attend, speak and vote on their behalf at the meeting. If you wish to appoint a person other than the Chair, please insert the name of your chosen proxy holder in the space provided (see reverse). If the proxy is being appointed in relation to less than your full voting entitlement, please enter in the box next to the proxy holder's name (see reverse) the number of shares in relation to which they are authorised to act as your proxy. If returned without an indication as to how the proxy shall vote on any particular matter, the proxy will exercise his or her discretion as to whether, and if so how, he or she votes (or if this proxy form has been issued in respect of a designated account for a shareholder, the proxy will exercise his or her discretion as to whether, and if so how, he or she votes).

• 2. To appoint more than one proxy, an additional proxy form(s) may be obtained by contacting the Registrar's helpline on 0370 707 1421 or you may photocopy this form. Please indicate in the box next to the proxy holder's name (see reverse) the number of shares in relation to which they are authorised to act as your proxy. Please also indicate by marking the box provided if the proxy instruction is one of multiple instructions being given. All forms must be signed and should be returned together in the same envelope.

• 3. The 'Vote Withheld' option overleaf is provided to enable you to abstain on any particular resolution. However, it should be noted that a 'Vote Withheld' is not a vote in law and will not be counted in the calculation of the proportion of the votes 'For' and 'Against' a resolution.

• 4. Pursuant to Regulation 41 of the Uncertificated Securities Regulations 2001, entitlement to attend and vote at the meeting and the number of votes which may be cast thereat will be determined by reference to the Register of Members of the Company at close of business on the day which is two days before the day of the meeting. Changes to entries on the Register of Members after that time shall be disregarded in determining the rights of any person to attend and vote at the meeting.

• 5. To appoint one or more proxies or to give an instruction to a proxy (whether previously appointed or otherwise) via the CREST system, CREST messages must be received by the issuer's agent (ID number 3RA50) by 11.00 am on 7 May 2024. For this purpose, the time of receipt will be taken to be the time (as determined by the timestamp generated by the CREST system) from which the issuer's agent is able to retrieve the message. The Company may treat as invalid a proxy appointment sent by CREST in the circumstances set out in Regulation

• 35(5)(a) of the Uncertificated Securities Regulations 2001.

• 6. The above is how your address appears on the Register of Members. If this information is incorrect please ring the Registrar's helpline on 0370 707 1421 to request a change of address form or go towww.investorcentre.co.ukto use the online Investor Centre service.

• 7. Any alterations made to this form should be initialled.

• 8. The completion and return of this form will not preclude a member from attending the meeting and voting in person.

Kindly Note: This form is issued only to the addressee(s) and is specific to the unique designated account printed hereon. This personalised form is not transferable between different: (i) account holders; or (ii) uniquely designated accounts. The Company and Computershare Investor Services PLC accept no liability for any instruction that does not comply with these conditions.

187726_231802_RUN_ONS/000001/000001/SG625//i

Form of Proxy

Please complete this box only if you wish to appoint a third party proxy other than the Chair. Please leave this box blank if you want to select the Chair. Do not insert your own name(s).

*

I/We hereby appoint the Chair of the Meeting OR the person indicated in the box above as my/our proxy to attend, speak and vote in respect of my/our full voting entitlement* on my/our behalf at the Annual General Meeting of Synthomer plc to be held at the offices of the Company, 45 Pall Mall, London SW1Y 5JG on 9 May 2024 at 11.00 am, and at any adjourned meeting.

* For the appointment of more than one proxy, please refer to Explanatory Note 2 (see front).

Please mark here to indicate that this proxy appointment is one of multiple appointments being made.

Please use a black pen. Mark with an X inside the box as shown in this example.

Vote

Ordinary Resolutions

• 1. To receive the Annual Report and Accounts for the year ended 31 December 2023.

  For Against WithheldVoteForAgainst Withheld

  • 11. To elect as a director Ms M Flöel.

• 2. To approve the Annual Report on Remuneration for the year ended 31 December 2023.

  • 12. To re-appoint PricewaterhouseCoopers LLP as auditor.

• 3. To re-elect as a director Mrs CA Johnstone.

  • 13. To authorise the Audit Committee to determine the remuneration of the auditor.

• 4. To re-elect as a director Mr M Willome.

• 5. To re-elect as a director Ms L Liu.

  • 14. To renew the authority of the directors to allot shares.

  Special Resolutions

  • 15. To authorise the Directors to disapply pre-emption rights.

• 6. To re-elect as a director the Hon AG Catto.

  • 16. To authorise the Directors to disapply pre-emption rights further for the purposes of financing an acquisition or other capital investment.

• 7. To re-elect as a director Mr RC Gualdoni.

  • 17. To give the directors authority to purchase the company's shares.

• 8. To re-elect as a director Dato' Lee Hau Hian.

• 9. To elect as a director Mr I Tyler.

• 10 To re-elect as a director Ms HA Van Deursen.

• 18. That a general meeting other than an annual general meeting may be called on not less than 14 clear days' notice.

Intention To Attend

Please indicate if you intend to attend the AGM

I/We instruct my/our proxy as indicated on this form. Unless otherwise instructed the proxy may vote as he or she sees fit or abstain in relation to any business of the meeting.

Signature

Date

H 1 0 4 1

In the case of a corporation, this proxy must be given under its common seal or be signed on its behalf by an attorney or officer duly authorised, stating their capacity (e.g. director, secretary).

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