THE FOLLOWING ANNOUNCEMENT IS BEING MADE PURSUANT TO THE REQUIREMENTS OF RULE 19.6(C) OF THE CITY CODE ON TAKEOVERS AND MERGERS (THE "CODE"), WHICH, INTER ALIA, REQUIRES A PARTY TO AN OFFER TO MAKE AN ANNOUNCEMENT AT THE END OF A PERIOD OF 12 MONTHS FROM THE DATE ON WHICH THE OFFER PERIOD ENDED CONFIRMING WHETHER IT HAS TAKEN, OR NOT TAKEN, THE COURSE OF ACTION SET OUT IN ITS STATED INTENTIONS

FOR IMMEDIATE RELEASE

CALGARY, Alberta, Oct. 31, 2025 (GLOBE NEWSWIRE) --

Gran Tierra Energy Inc. ( GTE ) ("Gran Tierra")

Rule 19.6(c) confirmation with respect to post-offer intention statements regarding i3 Energy plc ("i3 Energy")

Gran Tierra announces that, further to completion on 31 October 2024 of the recommended cash and shares acquisition of the entire issued and to be issued share capital of i3 Energy plc, which was implemented by way of a Court-sanctioned scheme of arrangement under Part 26 of the Companies Act 2006 and became effective on 31 October 2024, it has duly confirmed in writing to The Panel on Takeovers and Mergers in accordance with the requirements of Rule 19.6(c) of the Code that it has complied with the post-offer intention statements made pursuant to Rule 2.7(c)(viii) and Rule 24.2 of the Code, as detailed in its announcement made under Rule 2.7 of the Code on 19 August 2024 and in the scheme document published by i3 Energy on 29 August 2024.

Important Notices Relating to Financial Advisers

Stifel Nicolaus Europe Limited (“Stifel“), which is authorised and regulated by the FCA in the UK, is acting as financial adviser exclusively for Gran Tierra and no one else in connection with the matters referred to in this announcement and will not be responsible to anyone other than Gran Tierra for providing the protections afforded to its clients or for providing advice in relation to matters referred to in this announcement. Neither Stifel, nor any of its affiliates, owes or accepts any duty, liability or responsibility whatsoever (whether direct or indirect, whether in contract, in tort, under statute or otherwise) to any person who is not a client of Stifel in connection with this announcement, any statement contained herein or otherwise.

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Source: Gran Tierra Energy Inc. ( GTE )