Oreterra Metals Corp. (TSX-V: OTMC) (OTCID: OTMCF) (FSE: D4RO) (WKN: A421RQ)  is pleased to announce that the TSX Venture Exchange has provided final approval for, and the Company has now closed, the amending agreement dated April 27, 2026, as amended by a second amending agreement dated June 12, 2026, amending the terms of the January 31, 2022 royalty agreement between the Company and Enduro Metals Corporation, a TSXV listed Issuer. Pursuant to the Amending Agreement and the Second Amending Agreement, the Optionee has the option to acquire up to 50% of the 2% net smelter returns royalty interest held by the Company in the Optionee’s Newmont Lake Project, located adjacent to Oreterra’s Trek-Andrei property in BC’s Golden Triangle, in exchange for near-term consideration consisting of 3,900,00 shares (issued in full to Oreterra on closing) and cash valued at approximately $1.1 million ($175,000 of which was paid to Oreterra on closing) at current market prices, in addition to a potential future $22 million in staged and advanced royalty payments. Oreterra retains a 1% NSR for future exposure to the Newmont Lake Project.

About the Amending Agreement:

In order to fully exercise the option on the NSR, the Optionee must issue 3,900,000 common shares to the Company (issued on closing) and make aggregate payments of $550,000 to the Company over a period of two years, of which $175,000 was paid on closing, and payments of $375,000, $250,000 of which may be payable in cash or common shares of the Optionee during the Term. In addition, potential future consideration involves: (i) a $500,000 cash payment upon delivery of a maiden NI 43-101 compliant resource estimate (of which up to $300,000 may be satisfied through the issuance of common shares of the Optionee); (ii) a $1,750,000 cash payment and a $1,750,000 advance royalty payment upon completion of the first feasibility study in respect of the property; (iii) a $10,000,000 cash advance royalty payment upon a decision to proceed toward mine permitting; and (iv) a one-time payment of $8,000,000 prior to commencement of extraction to buy back 50% of the existing NSR.

About the Second Amending Agreement

The Second Amending Agreement further modifies the terms of the NSR Agreement, as amended on April 27, 2026 by establishing a deemed floor price of $0.135 for any share consideration that could potentially be payable to Orterra pursuant to the NSR Agreement.

Enduro’s Chief Financial Officer is also a director of Oreterra. The transaction was approved by the disinterested directors of Oreterra.

About Oreterra Metals Corp.

Oreterra Metals Corp. is a TSXV-listed mineral exploration company focused primarily on copper, gold and silver. The Company holds several wholly-owned porphyry copper-gold prospects in British Columbia’s Golden Triangle, the most significant of which is the newly-identified Trek South prospect located to the southeast of Teck-Newmont’s Galore Creek project, currently undergoing pre-feasibility studies. Following a highly successful $9.7 million financing closed in March, a maiden two-phase, approximately 10,000 metre drill program at Trek South is now fully funded, for completion this summer. Drilling will test a 1.6 km wide zone of intense porphyry-style alteration, mineralization and underlying coincident strong IP, MT and magnetic anomalies exposed by recent glacial retreat. In addition, the first significant exploration work since 2007 is now planned for Oreterra’s JW porphyry prospect, located to the northwest of the Galore Creek deposits.

Additional wholly-owned interests include two former producers in Nevada: the Kinkaid claims in the Walker Lane trend covering numerous shallow Au-Cu-Ag workings over what is believed to be one or more porphyry centres, and the Scossa mine property in the Sleeper trend which is a former high-grade gold producer. The Company also holds a 100% interest in the large-scale Lundmark-Akow Lake Au-Cu property adjacent to the northwest of the Musselwhite Mine, where past drilling by the Company returned highly encouraging, broad VMS-style Au-Cu intersections. Oreterra also retains an ongoing interest in several properties including a 2% NSR on McEwen Mining’s Hislop gold property in Ontario and a 2% NSR on Enduro Metals’ Newmont Lake Au-Cu-Ag property in BC. Technical presentations on each of the Kinkaid, Scossa and Lundmark-Akow Lake properties, authored by J. Biczok, P.Geo, are available at https://www.oreterra.com/investors.