Gran Tierra Energy

A portion of the Net Cash Proceeds is expected to be used to return capital to stockholders through a repurchase of the Company’s outstanding common shares (the “Share Repurchase” ), the structure, size and terms of which will be determined by the Board of Directors and announced separately, with the balance retained to fund the Company’s Canadian and Azerbaijan programs and for general corporate purposes.

SEC original ↗Gran Tierra Energy — Earnings release (8-K exhibit)EX-99Aug 5, 2026

Return of capital to stockholders The Transaction positions the Company to deliver significant value to stockholders through the potential Share Repurchase.

SEC original ↗Gran Tierra Energy — Earnings release (8-K exhibit)EX-99Aug 5, 2026

By repurchasing and canceling a number of its outstanding common shares, the Company expects to provide stockholders seeking liquidity with a tax-efficient opportunity to monetize a portion of their investment while enhancing per-share value for continuing stockholders.

SEC original ↗Gran Tierra Energy — Earnings release (8-K exhibit)EX-99Aug 5, 2026

Any contemplated Share Repurchase is conditional on the closing of the Transaction and the receipt of the stockholder approval described above.

SEC original ↗Gran Tierra Energy — Earnings release (8-K exhibit)EX-99Aug 5, 2026

If such stockholder approval is not obtained, the Company will not be able to proceed with the Share Repurchase as described, and the amount, nature and timing of any alternative return of capital to stockholders would need to be reconsidered and redetermined by the Company.

SEC original ↗Gran Tierra Energy — Earnings release (8-K exhibit)EX-99Aug 5, 2026

This figure includes the assumption by the Purchaser of the Company’s 9.750% Senior Secured Amortizing Notes due 2031 (the “ 2031 Notes ”) and 9.500% Senior Notes due 2029 (the “ 2029 Notes ” and, together with the 2031 Notes, the “Assumed Notes” ), as well as the prepayment facility (the “Prepayment Agreement” ).

SEC original ↗Gran Tierra Energy — Earnings release (8-K exhibit)EX-99Aug 5, 2026

Strategic Rationale Attractive valuation of the Divested Business The total consideration represents $1.33 billion which aligns to an after-tax net present value (discounted at 10%) of the Divested Business’s proved-plus-probable (2P) reserves of approximately $1.37 billion, as derived from the GTE McDaniel Reserves Report.

SEC original ↗Gran Tierra Energy — Earnings release (8-K exhibit)EX-99Aug 5, 2026

Opportunity to redefine the Company’s strategic priorities The Transaction is the result of Gran Tierra’s continuous strategic portfolio review and results in a step-change in the Company’s financial position and provides stockholders with a fully funded growth vehicle.

SEC original ↗Gran Tierra Energy — Earnings release (8-K exhibit)EX-99Aug 5, 2026

The Company believes the Transaction is strategically significant for Maurel & Prom, materially increasing its working-interest production and establishing Colombia and Ecuador as a core pillar of its portfolio.

SEC original ↗Gran Tierra Energy — Earnings release (8-K exhibit)EX-99Aug 5, 2026

, together with its subsidiaries, is an independent international energy company currently focused on oil and natural gas exploration and production in Canada, Colombia, Ecuador and Azerbaijan.

SEC original ↗Gran Tierra Energy — Earnings release (8-K exhibit)EX-99Aug 5, 2026

Upon completion of the Transaction described in this press release, the Company’s producing operations will be focused on Canada, and the Company will continue to pursue its exploration interests in Azerbaijan and additional new growth opportunities that would further strengthen the Company’s portfolio.

SEC original ↗Gran Tierra Energy — Earnings release (8-K exhibit)EX-99Aug 5, 2026

These statements are subject to risks and uncertainties.

SEC original ↗Gran Tierra Energy — Earnings release (8-K exhibit)EX-99Aug 5, 2026

Gran Tierra believes these assumptions to be reasonable at this time, but the forward-looking statements are subject to risks and uncertainties, many of which are beyond Gran Tierra’s control, which may cause actual results to differ materially from those implied or expressed by the forward-looking statements.

SEC original ↗Gran Tierra Energy — Earnings release (8-K exhibit)EX-99Aug 5, 2026

There are numerous uncertainties inherent in estimating quantities of crude oil and natural gas reserves and the future cash flows attributed to such reserves.

SEC original ↗Gran Tierra Energy — Earnings release (8-K exhibit)EX-99Aug 5, 2026

Complete disclosure regarding these resources, including the summary tables, the associated risks and level of uncertainty, the significant positive and negative factors relevant to the estimates, the specific contingencies, the chance of discovery, chance of development and chance of commerciality, and a description of the applicable projects, is contained in the Company’s press release dated August 4, 2026.

SEC original ↗Gran Tierra Energy — Earnings release (8-K exhibit)EX-99Aug 5, 2026

Given the uncertainty of discovery associated with the prospective resources, costs and timelines to production, as well as recovery technologies, cannot be determined at this time.

SEC original ↗Gran Tierra Energy — Earnings release (8-K exhibit)EX-99Aug 5, 2026