10 November 2025

Mosman Oil and Gas Limited

("Mosman" or the "Company")

Results of Annual General Meeting

Mosman Oil and Gas Limited (AIM: MSMN), advancing helium, hydrogen and hydrocarbon projects in the USA, announces that the 2025 Annual General Meeting ("AGM") was held in Sydney earlier today.

The Board is pleased to announce that all Resolutions were passed by way of a show of hands with overwhelming support via proxy.

The following proxies were received:

All resolutions were carried on a show of hands.

With regards to Resolutions 5 to 10, the Company provides notice this day that, in accordance with the approvals granted by shareholders, Mosman will proceed with the issue of shares to certain Directors and Persons Discharging Managerial Responsibilities ("PDMRs").

The number of shares to be issued has been determined based on the five-day volume weighted average price ("VWAP") of 0.0243 pence per share, being the VWAP for Mosman shares on AIM for the five trading days immediately prior to the AGM. As a result, Carl Dumbrell, Graham Duncan, Nigel Harvey, Andrew Scott, Tina Loh and Howard McLaughlin will each receive 60,950,617 shares, being 365,703,702 in total.

These shares will be issued to Directors and PDMRs as approved under Resolutions 5 to 10, and will be subject to a 12-month escrow period from the date of issue.

Admission to AIM and Total Voting Rights

Application will shortly be made to the London Stock Exchange for the PDMR shares, which will rank pari passu with the Company's existing issued ordinary shares, to be admitted to trading on AIM, with dealings expected to commence at 8.00 a.m. on 14 November 2025.

Following the issue of the PDMR shares, the Company's share and total voting rights will comprise 32,980,558,696 Ordinary Shares of no par value and the Company does not hold any shares in treasury.

Consequently, the above figure may be used by shareholders in the Company 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 share capital of the Company in accordance with the Companies' Articles.

Market Abuse Regulation (MAR) Disclosure

The information contained within this announcement is deemed by the Company to constitute inside information as stipulated under the Market Abuse Regulations (EU) No. 596/2014 ('MAR') which has been incorporated into UK law by the European Union (Withdrawal) Act 2018. Upon the publication of this announcement via Regulatory Information Service ('RIS'), this information is now considered to be in the public domain.

Enquiries:

Updates on the Company's activities are regularly posted on its website: www.mosmanoilandgas.com

Notes to editors

Mosman (AIM: MSMN) is a helium, hydrogen and hydrocarbon exploration, development, and production company with projects in the US and Australia. Mosman's strategic objectives remain consistent: to identify opportunities which will provide operating cash flow and have development upside, in conjunction with progressing exploration. The Company has several projects in the US, in addition to royalty interests in Australia.