THIS ANNOUNCEMENT AND THE INFORMATION CONTAINED HEREIN, IS RESTRICTED AND IS NOT FOR RELEASE, PUBLICATION, DISTRIBUTION OR FORWARDING, IN WHOLE OR IN PART, DIRECTLY OR INDIRECTLY, IN OR INTO THE UNITED STATES, AUSTRALIA, CANADA, JAPAN, THE REPUBLIC OF SOUTH AFRICA OR ANY OTHER JURISDICTION IN WHICH SUCH RELEASE, PUBLICATION OR DISTRIBUTION WOULD BE UNLAWFUL.

THIS ANNOUNCEMENT IS FOR INFORMATION PURPOSES ONLY AND IS NOT AN INVITATION, SOLICITATION, RECOMMENDATION, OFFER OR ADVICE TO ANY PERSON TO SUBSCRIBE FOR, OR OTHERWISE ACQUIRE, PURCHASE OR DISPOSE OF SECURITIES IN ANY JURISDICTION. PLEASE SEE THE IMPORTANT NOTICES AT THE END OF THIS ANNOUNCEMENT.

THIS ANNOUNCEMENT CONTAINS INSIDE INFORMATION FOR IMMEDIATE RELEASE.

27 August 2026

Rockhopper Exploration plc

("Rockhopper" or the "Company")

Results of Placing & Restoration of Trading

Rockhopper Exploration plc (AIM: RKH), the oil and gas company with key interests in the North Falkland Basin, is pleased to announce that the Company has raised approximately US$180 million (approximately £132.4 million) through the placing of 189,210,582 New Ordinary Shares (the "Placing Shares") with existing and new institutional investors at a fixed price of 70 pence per share (the "Issue Price") via an accelerated bookbuild (the "Placing").

The Placing attracted strong demand from existing and new institutional investors and was significantly oversubscribed at the Issue Price.

Canaccord Genuity Limited ("Canaccord") and Peel Hunt LLP ("Peel Hunt") acted as Joint Bookrunners in connection with the Placing.

The Placing Shares being issued represent approximately 22% of the existing issued ordinary share capital of the Company prior to the Placing. The Placing was conducted using the Company's existing share authorities.

Open Offer

As detailed in the Company's announcement of 27 August 2026 titled "Proposed Capital Raising", the Company has also launched an Open Offer to provide Qualifying Shareholders with the opportunity to subscribe for New Ordinary Shares at the Issue Price. A circular containing full details of the Open Offer and the expected timetable will be posted to Shareholders on 28 August 2026 and made available on the Company's website shortly thereafter.

Sam Moody, CEO of Rockhopper Exploration plc, said:

"We are delighted with the strong response from investors. The support reflects the compelling opportunity presented by Sea Lion and the value uplift to project Net Present Value, as highlighted in yesterday's announcement. We are also pleased to offer qualifying shareholders the opportunity to participate in this exciting development through the Open Offer."

Capital Access Window & Restoration of Trading

As detailed in the Company's announcement of 24 August 2026 titled "Sea Lion Update & Potential Capital Raise", the Company entered a Capital Access Window at 7:45 a.m. BST on 24 August 2026, in order to reach a broader range of investors during the Placing.

Following the results of the Placing, the Capital Access Window has now closed and normal trading in the Company's existing Ordinary Shares is expected to resume at 7:30 a.m. BST on 28 August 2026.

Admission & Total Voting Rights

Application has been made to the London Stock Exchange for the Placing Shares to be admitted to trading on AIM and admission is expected to become effective on or around 8.00 a.m. on 2 September 2026 ("Admission").

The Company confirms that, upon Admission of the Placing Shares to be issued pursuant to the Placing, the issued ordinary share capital of the Company will consist of 1,051,439,462 Ordinary Shares of 1 pence each in the capital of the Company and there will be no Ordinary Shares held in treasury. This issued share capital figure can be used by Shareholders as the denominator for the calculations by which they will determine if they are required to notify their interest in, or a change to their interest in, the Company under the FCA's Disclosure Guidance and Transparency Rules.

Other than where defined, capitalised terms used in this announcement have the meanings given to them in the announcement titled "Proposed Capital Raising" released by the Company at 7:00 a.m. BST on 27 August 2026.

Enquiries:

Rockhopper Exploration plc

Sam Moody - Chief Executive Officer

Tel. +44 (0)20 7390 0230 (via Vigo Consulting)

Canaccord Genuity Limited (Joint Bookrunner, NOMAD and Joint Broker)

Henry Fitzgerald-O'Connor/James Asensio/Charlie Hammond (Investment Banking)

Sam Lucas/Darren Furby (ECM)

Tel. +44 (0) 20 7523 8000

Peel Hunt LLP (Joint Bookrunner and Joint Broker)

Richard Crichton/ Georgia Langoulant

Sohail Akbar / Ambika Bose

Tel. +44 (0) 20 7418 8900

Vigo Consulting

Patrick d'Ancona/Ben Simons/Fiona Hetherington

Tel. +44 (0) 20 7390 0234

IMPORTANT INFORMATION

The information contained within this Announcement is deemed by the Company to constitute inside information as stipulated under Article 7 of the Market Abuse Regulation (EU) No. 596/2014 (as amended) as it forms part of the domestic law of the United Kingdom by virtue of the European Union (Withdrawal) Act 2018 (as amended). Upon the publication of this Announcement via the Regulatory Information Service, this inside information is now considered to be in the public domain.

This Announcement contains (or may contain) certain forward-looking statements with respect to certain of the Company's plans and its current goals and expectations relating to its future financial condition and performance and which involve a number of risks and uncertainties. The Company cautions readers that no forward-looking statement is a guarantee of future performance and that actual results could differ materially from those contained in the forward-looking statements. These forward-looking statements can be identified by the fact that they do not relate only to historical or current facts. Forward-looking statements sometimes use words such as "aim", "anticipate", "target", "expect", "estimate", "intend", "plan", "goal", "believe", or other words of similar meaning. By their nature, forward-looking statements involve risk and uncertainty because they relate to future events and circumstances, including, but not limited to, economic and business conditions, the effects of continued volatility in credit markets, market-related risks such as changes in the price of commodities or changes in interest rates and foreign exchange rates, the policies and actions of governmental and regulatory authorities, changes in legislation, the further development of standards and interpretations under International Financial Reporting Standards ("IFRS") applicable to past, current and future periods, evolving practices with regard to the interpretation and application of standards under IFRS, the outcome of pending and future litigation or regulatory investigations, the success of future explorations, acquisitions and other strategic transactions and the impact of competition. A number of these factors are beyond the Company's control. As a result, the Company's actual future results may differ materially from the plans, goals, and expectations set forth in the Company's forward-looking statements. You should not place undue reliance on forward-looking statements. Any forward-looking statements made in this Announcement by or on behalf of the Company speak only as of the date they are made. Except as required by the FCA, the London Stock Exchange or applicable law, the Company expressly disclaims any obligation or undertaking to release publicly any updates or revisions to any forward-looking statements contained in this Announcement to reflect any changes in the Company's expectations with regard thereto or any changes in events, conditions or circumstances on which any such statement is based.

This Announcement is for information purposes only and shall not constitute an offer to buy, sell, issue, or subscribe for, or the solicitation of an offer to buy, sell, issue, or subscribe for any securities, nor shall there be any offer, solicitation or sale of securities in any jurisdiction in which such offer, solicitation or sale would be unauthorised or unlawful prior to registration or qualification under the securities laws of any such jurisdiction. Any failure to comply with these restrictions may constitute a violation of the securities law of any such jurisdiction.

Neither this Announcement, nor any copy of it, may be released or otherwise forwarded, distributed, transmitted or sent in or into the United States. This Announcement is not an offer of securities for sale in or into the United States. The New Ordinary Shares have not been and will not be registered under the US Securities Act 1933, as amended (the "Securities Act") or with any securities regulatory authority of any state or other jurisdiction of the United States and may not be offered, sold, delivered, transferred, or taken up, directly or indirectly, in or into the United States except pursuant to an exemption from, or in a transaction not subject to, the registration requirements of the Securities Act and in compliance with any applicable securities laws of any state or other jurisdiction of the United States. The Company does not intend to register any portion of the Capital Raising in the United States or to conduct an offering of securities in the United States. The New Ordinary Shares are being offered and sold in "offshore transactions" as defined in, and in reliance on, Regulation S under the Securities Act.

This Announcement does not contain an offer or constitute any part of an offer to the public. This Announcement is not a "prospectus" within the meaning of Regulation 21(1) of the Public Offers and Admissions to Trading Regulations 2024 ("POATR") and a copy of it has not been, and will not be, delivered to any authority which could be a competent authority for the purpose of the Prospectus Regulation (EU) 2017/1129 (the "EU Prospectus Regulation"). The contents of this Announcement have not been examined or approved by the London Stock Exchange, nor has it been approved by an "authorised person" for the purposes of Section 21 of the FSMA. This Announcement is being distributed to persons in the United Kingdom only in circumstances in which section 21(1) of the FSMA does not apply.

This Announcement is directed only at: (a) persons in member states of the European Economic Area who are qualified investors within the meaning of article 2(e) of the EU Prospectus Regulation, and (b) if in the United Kingdom, persons who (i) have professional experience in matters relating to investments who fall within the definition of "investment professionals" in article 19(5) of the Financial Services and Markets Act 2000 (Financial Promotion) Order 2005, as amended (the "Order"), or are high net worth companies, unincorporated associations or partnerships or trustees of high value trusts as described in article 49(2) of the Order, and (ii) are qualified investors as defined in paragraph 15 of Part 2 of Schedule 1 of the POATR, and (c) otherwise, to persons to whom it may otherwise be lawful to communicate it (all such persons together being referred to as "Relevant Persons"). Any investment in connection with the Placing will only be available to, and will only be engaged with, Relevant Persons. Any person who is not a Relevant Person should not act or rely on this Announcement or any of its contents.

This document does not constitute a prospectus under the Israeli Securities Law, 5728-1968 (the "Israeli Securities Law"), and has not been filed with or approved by the Israel Securities Authority. In Israel, this document is being distributed only to, and is directed only at, and any offer of the Placing Shares is directed only at: (i) a limited number of persons in accordance with the Israeli Securities Law, and (ii) investors listed in the first addendum (the "Addendum") to the Israeli Securities Law, consisting primarily of joint investment in trust funds, provident funds, insurance companies, banks, portfolio managers, investment advisors, members of the Tel Aviv Stock Exchange, underwriters, venture capital funds, entities with equity in excess of NIS 50 million and 'qualified individuals', each as defined in the Addendum (as it may be amended from time to time), collectively referred to as qualified investors (in each case, purchasing for their own account or, where permitted under the Addendum, for the accounts of their clients who are investors listed in the Addendum). Qualified investors are required to submit written confirmation that they fall within the scope of the Addendum, are aware of the meaning of same and agree to it.

This Announcement has been issued by and is the sole responsibility of the Company. No representation or warranty, express or implied, is or will be made as to, or in relation to, and no responsibility or liability is or will be accepted by the Joint Bookrunners (apart from the responsibilities or liabilities that may be imposed by the FSMA or other regulatory regime established thereunder) or by any of their respective affiliates or agents as to, or in relation to, the accuracy or completeness of this Announcement or any other written or oral information made available to or publicly available to any interested party or its advisers, and any liability therefor is expressly disclaimed.

Canaccord Genuity Limited, which is authorised and regulated in the United Kingdom by the FCA, is acting as nominated adviser, joint bookrunner and joint broker for the Company and for no-one else in connection with the Placing, and Canaccord will not be responsible to anyone other than the Company for providing the protections afforded to its customers or for providing advice to any other person in relation to the Placing or any other matter referred to herein.

Peel Hunt LLP, which is authorised and regulated in the United Kingdom by the FCA, is acting as joint bookrunner and joint broker for the Company and for no-one else in connection with the Placing and Peel Hunt will not be responsible to anyone other than the Company for providing protections afforded to its customers or for providing advice to any other person in relation to the Placing or any other matter referred to herein.

The distribution of this Announcement and the offering of the New Ordinary Shares in certain jurisdictions may be restricted by law. No action has been taken by the Company, Canaccord or Peel Hunt that would permit an offering of such securities or possession or distribution of this Announcement or any other offering or publicity material relating to such securities in any jurisdiction where action for that purpose is required. Persons into whose possession this Announcement comes are required to inform themselves about, and to observe, such restrictions.

The Announcement does not constitute a recommendation concerning any investor's options with respect to the Placing. The New Ordinary Shares to which this Announcement relates may be illiquid and/or subject to restrictions on their resale. Prospective purchasers of the New Ordinary Shares should conduct their own due diligence, analysis and evaluation of the business and data described in this Announcement, including the New Ordinary Shares. The pricing and value of securities can go down as well as up. Past performance is not a guide to future performance. The contents of this Announcement are not to be construed as financial, legal, business or tax advice. If you do not understand the contents of this Announcement you should consult an authorised financial adviser, legal adviser, business adviser or tax adviser for financial, legal, business or tax advice.

The information in this Announcement may not be forwarded or distributed to any other person and may not be reproduced in any manner whatsoever. Any forwarding, distribution, dissemination, reproduction, or disclosure of this information in whole or in part is unauthorised. Failure to comply with this directive may result in a violation of the Securities Act or the applicable laws of other jurisdictions.

Neither the content of the Company's website nor any website accessible by hyperlinks on the Company's website is incorporated in, or forms part of, this Announcement.