Mast Energy Developments PLC

Major Shareholding Notification • Oct 20, 2025

National Storage Mechanism | Additional information

RNS Number : 0819E

Mast Energy Developments PLC

20 October 2025

Mast Energy Developments PLC

(Incorporated in England and Wales)

(Registration Number: 12886458)

LEI :213800HFVHGJ9YGO9F71

Share code on the LSE: MAST

ISIN: GB00BNG90H86

('MED' or 'the Company')

Dated: 20 October 2025

MAST Energy Developments PLC

TR-1: Standard form for notification of major holdings

1. Issuer Details

ISIN

GB00BNG90H86

Issuer Name

MAST ENERGY DEVELOPMENTS PLC

UK or Non-UK Issuer

UK

2. Reason for Notification

An acquisition or disposal of voting rights

3. Details of person subject to the notification obligation

Name

Peel Hunt LLP

City of registered office (if applicable)

London

Country of registered office (if applicable)

United Kingdom

4. Details of the shareholder

Full name of shareholder(s) if different from the person(s) subject to the notification obligation, above

City of registered office (if applicable)

Country of registered office (if applicable)

5. Date on which the threshold was crossed or reached

17-Oct-2025

6. Date on which Issuer notified

20-Oct-2025

7. Total positions of person(s) subject to the notification obligation

	% of voting rights attached to shares (total of 8.A)	% of voting rights through financial instruments (total of 8.B 1 + 8.B 2)	Total of both in % (8.A + 8.B)	Total number of voting rights held in issuer
Resulting situation on the date on which threshold was crossed or reached	10.861587	0.000000	10.861587	3450284
Position of previous notification (if applicable)

8. Notified details of the resulting situation on the date on which the threshold was crossed or reached

8A. Voting rights attached to shares

Class/Type of shares ISIN code(if possible)	Number of direct voting rights (DTR5.1)	Number of indirect voting rights (DTR5.2.1)	% of direct voting rights (DTR5.1)	% of indirect voting rights (DTR5.2.1)
GB00BNG90H86	3450284		10.861587
Sub Total 8.A	3450284		10.861587%

8B1. Financial Instruments according to (DTR5.3.1R.(1) (a))

Type of financial instrument	Expiration date	Exercise/conversion period	Number of voting rights that may be acquired if the instrument is exercised/converted	% of voting rights
Sub Total 8.B1

8B2. Financial Instruments with similar economic effect according to (DTR5.3.1R.(1) (b))

Type of financial instrument	Expiration date	Exercise/conversion period	Physical or cash settlement	Number of voting rights	% of voting rights
Sub Total 8.B2

9. Information in relation to the person subject to the notification obligation

1. Person subject to the notification obligation is not controlled by any natural person or legal entity and does not control any other undertaking(s) holding directly or indirectly an interest in the (underlying) issuer.

Ultimate controlling person	Name of controlled undertaking	% of voting rights if it equals or is higher than the notifiable threshold	% of voting rights through financial instruments if it equals or is higher than the notifiable threshold	Total of both if it equals or is higher than the notifiable threshold

10. In case of proxy voting

Name of the proxy holder

The number and % of voting rights held

The date until which the voting rights will be held

11. Additional Information

12. Date of Completion

20-Oct-2025

13. Place Of Completion

London

ENDS

This announcement contains inside information for the purposes of the UK version of the Market Abuse Regulation (EU No. 596/2014) as it forms part of United Kingdom domestic law by virtue of the European Union (Withdrawal) Act 2018 ('UK MAR'). Upon the publication of this announcement, this inside information is now considered to be in the public domain.

Pieter Krügel	[email protected]	Mast Energy Developments PLC	CEO
Guy Wheatley, CFA	+44 (0)74 9398 9014	Fortified Securities	Corporate Broker

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