Gulf Marine Services PLC

2 June 2025

This announcement contains inside information and is provided in accordance with the requirements of Article 17 of the Market Abuse Regulation (EU) No. 596/2014 (as it forms part of UK law by virtue of the European Union (Withdrawal) Act 2018, as amended).

Gulf Marine Services PLC

('Gulf Marine Services', 'GMS', 'the Company' or 'the Group')

Request to Call a General Meeting

Gulf Marine Services (GMS), a leading provider of self-propelled, self-elevating support vessels to the offshore energy industry, announces that on 30 May 2025 it received a request to convene a general meeting, proposing certain changes to the Board and the payment of a dividend. The Company understands that the request has been shared with certain other shareholders of the Company.

This request follows on from a similar request from the same parties announced on 14 May 2025, determined to be invalid as announced on 23 May 2025, following which the parties making the request were invited to engage in dialogue with the Company. The Company is disappointed to note that those parties have not subsequently engaged in dialogue with the Company before making this further request. The Company is, though, pleased to have received support from more than 96% of shareholders voting on the resolutions at the Company's Annual General Meeting held on 29 May 2025, the full results of which were announced that day.

The Company is seeking legal advice as to the validity of this request and a further announcement will be made in due course. Shareholders are advised to take no action in relation to this matter at this time.

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Notes to Editors:

Gulf Marine Services PLC, a company listed on the London Stock Exchange, was founded in Abu Dhabi in 1977 and has become a world-leading provider of advanced self-propelled self-elevating support vessels (SESVs). The fleet serves the offshore energy industries from its offices in the United Arab Emirates, Saudi Arabia, Qatar and the United Kingdom. The Group's assets are capable of serving clients' requirements across the globe, including those in the Middle East, Europe, South East Asia, West Africa, North and South America, and the Gulf of Mexico.

The GMS fleet of 14 SESVs is amongst the youngest in the industry. The vessels support GMS's clients in a broad range of offshore platform refurbishment and maintenance activities, well intervention work, and offshore wind turbine maintenance work (which are opex-led activities), as well as offshore platform installation and decommissioning and offshore wind turbine installation (which are capex-led activities).

The SESVs are categorised by size - K-Class (Small), S-Class (Mid), and E-Class (Large) - with these capable of operating in water depths of 45m to 80m depending on leg length. The vessels are four-legged and are self-propelled, which means they do not require tugs or similar support vessels for moves between locations in the field; this makes them significantly more cost-effective and time-efficient than conventional offshore support vessels without self-propulsion. They have a large deck space, crane capacity, and accommodation facilities (for up to 300 people) that can be adapted to the requirements of the Group's clients.

Gulf Marine Services PLC's Legal Entity Identifier is 213800IGS2QE89SAJF77 www.gmsplc.com

MAR

This announcement contains inside information and is provided in accordance with the requirements of Article 17 of the Market Abuse Regulation (EU) No. 596/2014 (as it forms part of UK law by virtue of the European Union (Withdrawal) Act 2018, as amended).  Upon the publication of this announcement via a Regulatory Information Service, this inside information will be considered to be in the public domain.

The person responsible for arranging for the release of this announcement on behalf of GMS is Tony Hunter, Company Secretary.

Disclaimer

The content of the Gulf Marine Services PLC website should not be considered to form a part of or be incorporated into this announcement.

Cautionary Statement

This announcement includes statements that are forward‐looking in nature. All statements other than statements of historical fact are capable of interpretation as forward‐looking statements. These statements may generally, but not always, be identified by the use of words such as 'will', 'should', 'could', 'estimate', 'goals', 'outlook', 'probably', 'project', 'risks', 'schedule', 'seek', 'target', 'expects', 'is expected to', 'aims', 'may', 'objective', 'is likely to', 'intends', 'believes', 'anticipates', 'plans', 'we see' or similar expressions. By their nature these forward‐looking statements involve numerous assumptions, risks and uncertainties, both general and specific, as they relate to events and depend on circumstances that might occur in the future.

Accordingly, the actual results, operations, performance or achievements of the Company and its subsidiaries may be materially different from any future results, operations, performance or achievements expressed or implied by such forward‐looking statements, due to known and unknown risks, uncertainties and other factors. Neither Gulf Marine Services PLC nor any of its subsidiaries undertake any obligation to publicly update or revise any forward‐looking statement as a result of new information, future events or other information. No part of this announcement constitutes, or shall be taken to constitute, an invitation or inducement to invest the Company or any other entity and must not be relied upon in any way in connection with any investment decision. All written and oral forward‐looking statements attributable to the Company or to persons acting on the Company's behalf are expressly qualified in their entirety by the cautionary statements referred to above.