Eni S p A : Sub-Proxy form Designated representative art. 135-novies TUF

Eni S.p.A.

Ordinary and Extraordinary Shareholders' Meeting called for 15 May 2024 at 10:00 a.m., on single call in Rome, Piazzale Enrico Mattei, 1

FORM FOR GRANTING A SUB-PROXY TO THE SHAREHOLDERS'

REPRESENTATIVE

STUDIO LEGALE TREVISAN & ASSOCIATI 1

pursuant to Article 135-novies of the Consolidated Law on Finance (Legislative Decree 58/98)

The undersigned

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Company name - Surname and name

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Tax ID no.Date of birthP l a c e o f b i r t hProvince of birth

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no. ____________voting Shareholders, as per copy of proxies granted by each entitled Shareholder,

declaring, under his own responsibility, the compliance of the proxy form to the original and the identity of the delegating parties, in name of and on behalf of the same.

SUB-DELEGATES

Studio Legale Trevisan & Associati, with registered office in Milan, Viale Majno 45, in the person of Dario Trevisan, attorney, born in Milan on 4 May 1964 (Tax ID no. TRVDRA64E04F205I), who may be replaced by Camilla Clerici, attorney, born in Genoa on 19 January 1973 (Tax ID no. CLRCLL73A59D969J), or by Giulio Tonelli, attorney, born in La Spezia on 27 February 1979 (Tax ID no. TNLGLI79B27E463Q), or by Alessia Giacomazzi, attorney, born in a Castelfranco Veneto (TV) on 5 September 1985 (Tax ID no. GCMLSS85P45C111T), or by Gaetano Faconda, attorney, born in Trani (BT) on 2 October 1985 (Tax ID no. PRLVLR84R64F952S) or by Valeria Proli, attorney, born in Novara on 24 October 1984 (Tax ID no. PRLVLR84R64F952S) or by Raffaella Cortellino, born in Barletta (BT) on 4 June 1989 (Tax ID no.

1 All persons entitled to participate in the Shareholders' meeting must be represented by way of a written proxy or sub-proxyin accordance with applicable law and for this purpose may use this sub-proxyform available on the Company's website at www.eni.com, in the section "2024 Shareholders' Meeting". Sub-proxies, with attachments, should be received by 12 noon on 14 May 2024 at

Studio Legale Trevisan & Associati by post at the address Viale Majno n. 45, 20122 - Milan - Italy or by certified e-mail to: rappresentante-designato@pec.it or to the e-mail address: rappresentante-designato@trevisanlaw.it. For organisational reasons, proxy, with attachments, should also be notified to the Company, without voting instructions, by certified e-mail at the following address: corporate_sesocorp@pec.eni.com or b) through the appropriate above-mentioned section of the Company's website dedicated to the Shareholders' Meeting, in accordance with the procedures specified therein.

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CRTRFL89H44A669V), or by Andrea Ferrero, attorney, born in Torino on 5 May 1987 (Tax ID no. FRRNDR87E05L219F), or by Marcello Casazza, attorney, born in Vigevano (PV) on 3 September 1991 (Tax ID no. CSZMCL91P03L872S), or by Serena Larghi born in Varese (VA) on 27 November 1992 (Tax ID no. LRGSRN92S67L682Q), or by Massimo Rosica born in Roma on 12 March 1985 (Tax ID no. RSCMSM85C12H501S), or by Mollicone Marta Mariolina born in Roma on 1 October 1991 (Tax ID no. MLLMTM91R41H501V), or by Lorenzo De Santis born in Roma on 10 October1987 (Tax ID no. DSNLNZ87R10H501B), all domiciled for the purposes of this proxy at Studio Legale Trevisan & Associati, Viale Majno n. 45, 20122 - Milan (hereinafter, individually or collectively, the "Sub-Proxyholder") to represent me/us for all the above-mentioned shares for which I/we am/are entitled to vote in the Shareholders' Meeting of Eni S.p.A. called in Rome, Piazzale Enrico Mattei, 1, for 15 May 2024, at 10:00 a.m., on single call, granting him/her the powers necessary to exercise the voting rights in my name and on my behalf in conformity with the instructions given.

Studio Legale Trevisan & Associati, declares not to have any interest on our own behalf in respect of the proposed resolutions. Nevertheless, in view of the contractual relationship with the Company, for all statutory purposes expressly declares that if unknown circumstances should arise or changes or additions made to the items submitted to the Shareholders Meeting, he and/or his replacements will not vote differently from the voting instructions received.

The undersigned DECLARES that he/she is aware:

1. of the fact that the proxy may contain voting instructions for only some of the proposed resolutions on the agenda and that, in this case, the vote shall be exercised only for those proposals for which voting instructions are given;
2. of the fact that in any case the shares for which the proxy has been granted, even partially, are calculated for the purposes of determining the due constitution of the meeting and, in relation to proposals for which no voting instructions have been conferred, the shares are not counted in the calculation of the majority and the share of capital required for the approval of the resolutions;
3. of the fact that the validity of the proxy form is subject to receipt by Eni S.p.A. of the notice of the authorised intermediary, at the request of the person entitled.

By granting this proxy, the person granting proxy declares that he/she is not subject to any prohibitions that prevent or limit in any way the right to attend and vote in the Shareholders' meeting, also within any sanctions and restrictive measures adopted at national and international level.

2 In the case of a legal person, indicate the appropriate stamp.

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Attachments:

1. Copy of the credit certification issued by bank or intermediary;
2. Copy of ID card or equivalent document of the proxyholder granting the sub-proxy and, in the case of a legal person, documentation demonstrating signature powers;
3. Copy of proxies granted by each entitled Shareholder and subject to sub-proxy;
4. Voting instructions.

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It is recommended that the following documents:

1. Sub-Proxy;
2. Copy of the credit certification issued by bank or intermediary;
3. Copy of ID card or equivalent document of the proxyholder granting the sub-proxy and, in the case of a legal person, documentation demonstrating signature powers;
4. Voting instructions,

will be delivered by 12 noon on 14 May 2024 to Studio Legale Trevisan & Associati by post at the address: Viale Majno n. 45, 20122 - Milan - Italy or by certified e-mail to: rappresentante-designato@pec.it or to the e-mail address: rappresentante-designato@trevisanlaw.it.

For organisational reasons, the proxies and sub-proxies, without voting instructions, should also be delivered to the Company by 12 noon on 14 May 2024 a) by certified e-mail to: corporate_sesocorp@pec.eni.com or b) using the above-mentioned section of the Company's website dedicated to the Shareholders' Meeting, in accordance with the procedures indicated therein.

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VOTING

INSTRUCTIONS

(Information for the Sub-proxyholder- check the appropriate box)

Mr./Mrs./Ms.

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(insert name of person granting sub-proxy or, if more than one, please attach list of the persons granting sub-proxy voting in the same way for all proxies granted to the proxyholder who will subscribe this form on behalf of them)

or in the case of a legal person

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(insert name of company/entity granting sub-proxy) (see above)

AUTHORISES

the Sub-Proxyholder3 to vote in accordance with the voting instructions for the Ordinary and Extraordinary Shareholders' Meeting of Eni S.p.A. in respect of_____________ Eni S.p.A. shares ISIN IT0003132476

called in Rome, Piazzale Enrico Mattei, 1, for 15 May 2024 at 10:00 a.m., on single call.

DECLARES

that he/she is aware:

1. of the fact that the proxy may contain voting instructions for only some of the proposed resolutions on the agenda and that, in this case, the vote shall be exercised only for those proposals for which voting instructions are given;
2. of the fact that in any case the shares for which the proxy has been granted, even partially, are calculated for the purposes of determining the due constitution of the meeting and, in relation to proposals for which no voting instructions have been conferred, the shares are not counted in the calculation of the majority and the share of capital required for the approval of the resolutions;
3. of the fact that the validity of the proxy form is subject to receipt by Eni S.p.A. of the notice of the authorised intermediary, at the request of the entitled person.

3 Note that the person granting the sub-proxy may participate in the Shareholders' Meeting and exercise the right to vote exclusively through the Shareholders' Representative (Studio Legale Trevisan & Associati, as indicated above) only if the Company has received the notice of the authorised intermediary referred to in Article 83-sexies of Legislative Decree 58/1998.

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Space for any other instructions and declarations.

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