Mr. Chuck Downie reports

EAGLE PLAINS' PARTNER SUN SUMMIT APPROVES 2026 EXPLORATION FOR THE THEORY PROJECT, TOODOGGONE DISTRICT, BC

Eagle Plains Resources Ltd. partner Sun Summit Minerals Corp. has approved the 2026 exploration plan at Eagle Plains' Theory copper-gold project, Toodoggone mining district, north-central British Columbia. The property is owned 100 per cent by Eagle Plains, with 122 hectares of the property subject to an underlying 0.5-per-cent net smelter royalty held by a third party.

The 9,677-hectare Theory project borders Thesis Gold's Ranch project to the north and is located within 10 kilometres to the northwest of Sun Summit's JD project. Sun Summit has an exclusive option agreement with Eagle Plains to earn up to a 100-per-cent interest in the project, located in the highly prospective Toodoggone mining district (see press release dated March 17, 2025).

Theory project 2026 exploration program

The 2026 work program will build on the success from the 2025 field season, the first significant fieldwork on the property in over 30 years (see press release dated Jan. 21, 2026).

The 2026 program will be executed in three phases. Phase 1 work will consist of a property-scale, 250-metre line spaced, airborne magnetotelluric survey to image subsurface resistivity and help locate causative intrusions and possible conduits for mineralization. The MobileMT survey will be completed by Expert Geophysics Surveys Inc. of Newmarket, Ont., under the guidance of geophysicist, Andrei Bagrianski, PGeo.

Phase 2 fieldwork will include mapping/prospecting and rock, soil, silt geochemical sampling with crews based out of temporary, helicopter-supported, camps. Work will focus on the detailed evaluation of targets identified by 2025 fieldwork, assessment of areas of interest generated by the MobileMT survey, and continuing target generation and assessment in underexplored areas of the property.

Phase 3 will include induced polarization (IP) surveys conducted by Peter E. Walcott and Associates Ltd. over high-priority target areas.

The results from the 2026 work program will be analyzed and modelled to identify and prioritize targets for 2027 drill testing. The proposed work program will have a budget of approximately $700,000.

Fieldwork will be managed by TerraLogic Exploration Inc. and is anticipated to begin in early June and continue into September. Eagle Plains is the project operator.

Highlights from 2025 field program

2025 work included:

• Data compilation with rectification and analysis of historical surface sampling and reconnaissance mapping;
• Remote sensing acquisition of district-and property-scale data sets, focusing on VNIR and SWIR bands to identify mineral groups diagnostic of epithermal and porphyry alteration;
• Field program consisting of prospecting, detailed geological mapping, and systematic rock, soil and silt geochemical sampling on targets identified through data analyses.

Saboteur zone: new high-grade copper discovery

• Three-kilometre length zone of copper mineralization associated with coincident magnetic high transition zone and strong radiometric potassic alteration anomaly;
• 15 of the rock samples collected returned over 1 per cent Cu (copper);
• Grab sample LSTHR040: 4.78 per cent copper, 0.635 gram per tonne gold, 49 g/t silver.

BEV zone:

• Broad copper soil and silt geochemical anomaly associated with multiphase alteration;
• Grab sample BLTHR029: 1.44 per cent copper, 0.043 g/t gold and 12.8 g/t silver.

Fred-DM-DMR zone:

• 1.6 km by three km zone of copper mineralization associated with barite veining;
• Grab sample BLTHR051: 6.42 per cent copper, 0.088 g/t gold, 99 g/t silver;
• Grab sample JBTHR008: 0.65 per cent copper, 12.6 g/t gold, 3,150 g/t silver.

Petrographic analyses of 2025 samples identified strong epidote-chlorite-carbonate alteration directly with hypogene copper mineralization (chalcopyrite-bornite-chalcocite). This type of mineralization and alteration assemblage is interpreted to represent the inner shell of a porphyry system, which may indicate a proximal source for some of the Theory mineralization.

About the Theory project

The 9,676 ha Theory project is located in Northern B.C. within the Toodoggone mining district. The district is endowed with both epithermal gold and porphyry copper-gold deposits, most notably the past-producing Kemess mine owned by Centerra Gold. The Omineca Resource Road provides access to the region from Mackenzie, B.C. Recent road upgrades completed in 2023 by Thesis Gold on its Lawyers-Ranch project brought road access to within eight kilometres of the Theory project.

Geology in the Theory region primarily comprises lower Jurassic Hazelton Group volcanics which unconformably overlie late Triassic Takla Group volcanics. The entire package of rocks is intruded by late Triassic and early Jurassic stocks. The majority of the Theory property encompasses the highly prospective Jurassic-Triassic unconformity (about 200 million years ago (Ma), termed by the B.C. Geologic Survey as the Red-Line, which is known to have a high spatial correlation to many of the known deposits throughout the Golden Triangle and Toodoggone.

Exploration by previous operators has been intermittent since the mid-1960s and regional government surveys are sparse, however encouraging mineralization and alteration commonly associated with both epithermal and porphyry systems has been documented. The most significant documented work was completed in 1988 in the north and west areas of the Theory project area. Work consisted primarily of alpine ridge and subalpine prospecting traverses as well as reconnaissance soil sample lines in areas where no outcrop was present. This work documented occurrences of low-sulphidation epithermal-related mineralization including quartz-barite veins with up to 8.2 g/t Au, 195 g/t Ag and 6.2 per cent Cu at the DM occurrence (B.C. Minfile 094E 231); and a quartz carbonate vein system with up to 6.8 g/t Au and 1,480 g/t Ag at the Fred-1 occurrence (B.C. Minfile 094E 402). The BEV occurrences (B.C. Minfile 094E 259), interpreted as a Cu-Au porphyry target, returned select historical rock results up to 0.47 per cent Cu, 10.5 g/t Ag and 0.13 g/t Au. Detailed soils revealed a 1.6-by-two-kilometre copper-in-soil anomaly with peak soil results to 920 parts per million Cu. Very little work is documented in the south and eastern parts of the property.

Recent exploration success in the area has been highlighted by Thesis Gold's announcement at its Lawyers-Ranch project of a combined measured and indicated mineral resource of 4,564,000 ounces grading 1.21 g/t AuEq (gold equivalent) and inferred resources of 643,000 oz grading 1.23 g/t AuEq (Lawyers-Ranch project National Instrument 43-101 technical report and prefeasibility study British Columbia, Canada, effective date: Dec. 1, 2025) and by Amarc Resources' new high-grade copper-gold-silver discovery at the AuRORA zone of the Joy project (Amarc Resources, Jan. 17, 2025, news release).

In late 2023 Eagle Plains acquired the property through staking and third party agreements. After undertaking initial compilation and interpretation of historical data on the project, Eagle Plains completed a property-wide, high-resolution airborne magnetic and radiometric survey in July, 2024, followed by fieldwork in 2025.

Management cautions that historical results were collected and reported by past operators and have not been verified nor confirmed by a qualified person but form a basis for continuing work on the subject properties. Management cautions that past results or discoveries on proximate land are not necessarily indicative of the results that may be achieved on the subject properties.

Qualified person

Technical information in this news release has been reviewed and approved by C.C. Downie, PGeo, a director and officer of Eagle Plains, hereby identified as the qualified person under National Instrument 43-101.

About Eagle Plains Resources Ltd.

Based in Cranbrook, B.C., Eagle Plains is a well-financed, prolific project generator that continues to conduct research, acquire and explore mineral projects throughout Western Canada, with a focus on critical metals integral to an increasingly electrified, decarbonized economy.

The company was formed in 1992 and is the fourth-oldest listed issuer on the TSX-V (and the only one of these four that has not seen a rollback or restructuring of its shares). Eagle Plains has continued to deliver shareholder value over the years and through numerous spin outs has transferred over $115-million in value directly to its shareholders, with Copper Canyon Resources and Taiga Gold Corp. being notable examples. Eagle Plains latest spinout, Eagle Royalties Ltd. (CSE: ER) was listed on May 24, 2023, and on Oct. 30, 2025, ER shareholders overwhelmingly approved a three-cornered amalgamation that resulted in a reverse takeover of Eagle Royalties by Summit Royalty Corp. The resulting issuer is named Summit Royalties Ltd. and trades under the symbol SUM on the TSX Venture Exchange with a market capitalization of over $100-million.

On Oct. 2, 2024, Eagle Plains announced the formation of a separate division within the company that will give Eagle Plains' shareholders direct exposure to strategic opportunities in Canadian green energy transition. As a wholly owned subsidiary of Eagle Plains, Osprey Power Inc. (OP) will focus on identifying and advancing innovative and diverse clean energy project portfolios in target markets throughout Canada, with an initial focus on Western Canada.

Eagle Plains' core business is acquiring grassroots critical- and precious-metal exploration properties. The company is committed to steadily enhancing shareholder value by advancing the company's diverse portfolio of projects toward discovery through collaborative partnerships and development of a highly experienced technical team.

Expenditures from 2010 to 2025 on Eagle Plains-related projects exceed $41-million, the majority of which was financed by third party partners. This exploration work resulted in approximately 50,000 metres of diamond drilling and extensive ground-based exploration work facilitating the advancement of numerous projects at various stages of development.

Throughout the exploration process, the company's mission is to help maintain prosperous communities by exploring for and discovering resource opportunities while building lasting relationships through honest and respectful business practices.

We seek Safe Harbor.