Mendell Helium plc

("Mendell Helium" or the "Company")

Exercise of Convertible Loan Notes

Mendell Helium (LON: MDH), the helium production company with operations in Kansas, announces that it has received notice to exercise convertible loan notes ("Conversion") over 9,799,999 new ordinary shares at an exercise price of 3 pence per share ("New Ordinary Shares"), generating cash proceeds for the Company of £280,000.

The New Ordinary Shares issued also reflect the 5% fee due on Conversion (which is itself payable through the issue of New Ordinary Shares). Following Conversion, the Company has no further convertible loan notes outstanding.

The convertible loan notes were issued in December 2025 as part of a fundraising at that time.

Admission

Application has been made for 9,799,999 New Ordinary Shares to be admitted to trading on AIM ("Admission"). Admission is expected to occur at 8:00 a.m. on or around 28 August 2026. The New Ordinary Shares will rank pari passu with the existing Ordinary Shares.

Total Voting Rights

Following Admission, the Company's enlarged share capital will comprise 354,836,937 Ordinary Shares of 1 pence each. Therefore, the total number of voting rights in the Company will be 354,836,937. This figure may be used by shareholders as the denominator for calculations by which they will determine if they are required to notify their interest in the Company, or a change to their interest in the Company, under the Financial Conduct Authority's Disclosure Guidance and Transparency Rules.

ENDS

Engage with the Mendell Helium management team directly by asking questions, watching video
summaries and seeing what other shareholders have to say. Navigate to our Interactive Investor
website here: https://mendellhelium.com/link/PKa6Ve

Enquiries:

Overview of Mendell Helium

Mendell Helium is a helium producer in Kansas, USA where it operates through its wholly owned subsidiary M3 Helium.

M3 Helium's flagship well, Rost 1-26, is in Fort Dodge, just to the east of Dodge City, Kansas. It has been tested as containing 5.1% helium composition and a drill stem test yielded a maximum flow rate of approximately 2,900 Mcf per day. Water removed from Rost 1-26 is delivered to Brobee, a nearby disposal well that has been permitted at 10,000 barrels of water per day at 1,200 psi.  Production at Rost 1-26 commenced in early November 2025 and the most recently recorded flow rate in December 2025 was 250 Mcf per day equating to approximately $1.4 million of helium per year (at $300/Mcf helium).

M3 Helium has subsequently drilled and completed a second well, Rost 2-26, which is currently being de-watered. It also owns additional leases in the Fort Dodge area capable of supporting up to eight new production wells. It has also agreed a joint venture with Ritchie Exploration, Inc. to recomplete the Schneweis Ventures 13A, a well with a drill stem test of over 10,000 Mcf per day and a historic flow rate of 300 Mcf per day.

At the Rost wells in Fort Dodge, M3 Helium treats the raw gas on site to concentrate the helium and has leased two tube trailers which it uses for deliveries to its offtaker.

M3 Helium also has interests in five producing wells (Peyton, Smith, Nilson, Bearman and Dimmitt) within the Hugoton gas field in South-Western Kansas, one of the largest natural gas fields in North America. Significantly these wells are in the proximity of a gathering network and the Jayhawk gas processing plant meaning that producing wells are all tied into the infrastructure.