MASTERMYNE GROUP LIMITED — Director's Dealing 2025

Nov 30, 2025

Appendix 3Y Change of Director’s Interest Notice

Rule 3.19A.2

Appendix 3Y

Change of Director’s Interest Notice

Information or documents not available now must be given to ASX as soon as available. Information and documents given to ASX become ASX’s property and may be made public.

Introduced 30/09/01 Amended 01/01/11

Name of entity Mastermyne Group Limited ABN 96 142 490 579

We (the entity) give ASX the following information under listing rule 3.19A.2 and as agent for the director for the purposes of section 205G of the Corporations Act.

Name of Director	Andrew Dominic Watts
Date of last notice	31 December 2024

Part 1 - Change of director’s relevant interests in securities

In the case of a trust, this includes interests in the trust made available by the responsible entity of the trust

Note: In the case of a company, interests which come within paragraph (i) of the definition of “notifiable interest of a director” should be disclosed in this part.

Direct or indirect interest	1. Indirect
Nature of indirect interest (including registered holder) Note: Provide details of the circumstances giving rise to the relevant interest.	(a) Interest held by Carm NQ Pty Ltd ATF The Carnhogan Family Trust, of which Mr Watts is sole director/shareholder of the Company and a beneficiary of the trust. (b) Interest held by Circle of Five Pty Ltd ATF Calypso Tours Trust, of which Mr Watts is a director of the Company and has a 1/3 interest in the trust held by his related party Carm NQ Pty Ltd ATF The Carnhogan Family Trust. (c) Interest held by Watty Pty Ltd ATF The Watty Super Fund, of which Mr Watts is director/shareholder of the Company and a member of the super fund.
Date of change	27 November 2025

• See chapter 19 for defined terms.

01/01/2011

Appendix 3Y Page 1

Appendix 3Y Change of Director’s Interest Notice

No. of securities held prior to change	Ordinary Shares: (a) 2,576,475 (b) 119,000 (c) 12,156,919 Options: (a) 179,578 (b) - (c) 538,959
Class	Ordinary Shares
Number acquired	Ordinary Shares: (a) - (b) - (c) 125,690
Number disposed	Ordinary Shares: (a) - (b) - (c) -
Value/Consideration Note: If consideration is non-cash, provide details and estimated valuation	Ordinary Shares: $0.1432 per Ordinary Share
No. of securities held after change	Ordinary Shares: (a) 2,576,475 (b) 119,000 (c) 12,282,609 Options: (a) 179,578 (b) - (c) 538,959
Nature of change Example: on-market trade, off-market trade, exercise of options, issue of securities under dividend reinvestment plan, participation in buy- back	Ordinary Shares issued under NED Plan, as approved by shareholders at the 2025 Annual General Meeting.

Part 2 – Change of director’s interests in contracts

Note: In the case of a company, interests which come within paragraph (ii) of the definition of “notifiable interest of a director” should be disclosed in this part.

Detail of contract

Not Applicable

• See chapter 19 for defined terms.

Appendix 3Y Page 2

01/01/2011

Appendix 3Y Change of Director’s Interest Notice

Nature of interest Name of registered holder (if issued securities) Date of change No. and class of securities to which interest related prior to change Note: Details are only required for a contract in relation to which the interest has changed Interest acquired Interest disposed Value/Consideration Note: If consideration is non-cash, provide details and an estimated valuation Interest after change

Part 3 –[+] Closed period

Were the interests in the securities or contracts detailed Not Applicable above traded during a[+] closed period where prior written clearance was required? If so, was prior written clearance provided to allow the trade to proceed during this period? If prior written clearance was provided, on what date was this provided?

• See chapter 19 for defined terms.

01/01/2011

Appendix 3Y Page 3