Northisle Provides Update on Largest Ever Field Program at North Island

Executive Summary

• Northisle has expanded its 2025 drilling program to ~27,000 m (up from the original 7,000 m), with 11,915 m already completed across 35 holes.
• Completed a C$39.5 million financing and several key project milestones, including an updated Preliminary Economic Assessment and commencement of Phase V exploration.
• The company outlined an extensive schedule of upcoming deliverables (assay results, metallurgical testing, pre‑feasibility study) and announced continued regional exploration, environmental baseline work, and investor outreach events through early 2026.

Key Details

• Drilling Expansion: Original Phase IV plan of 7,000 m increased to >27,000 m for 2025 – a near‑quadruple increase.
• Completed Drilling (as of Sep 30, 2025): 11,915 m in 35 holes; ~8,000 m of exploration drilling completed. Remaining: up to 15,000 m of infill, geotech and condemnation drilling.
• Target Rigs: Plan to operate up to four drill rigs by year‑end 2025.
• Staffing: Exploration office footprint and staff more than doubled to support the expanded program.
• Key Drill Intercepts (West Goodspeed): Thick, economically significant intervals in holes GS25‑17, GS25‑18, GS25‑23 indicating continuity of mineralization; assay results pending for remaining holes.
• Cougar Target: Three holes completed; visual confirmation of copper sulfides and alteration; assays pending.
• Northwest Expo & Goodspeed Exploration Holes: Step‑out hole intersected alteration and sulfide mineralization (assays pending); one exploration hole at Goodspeed returned no significant mineralization.
• Infill Drilling for Resource Upgrade: 4 infill holes at Red Dog and 5 at Northwest Expo completed; all pending assay results, aimed at converting Inferred resources to Indicated.
• Phase IV Results: Final assay results from West Goodspeed and NW Expo expected Q4 2025.
• Baseline & Geotech Studies: Comprehensive baseline studies (aquatics, terrestrial, hydrogeological, geochemical) initiated; geotechnical site investigation underway, slated for completion by end‑2025.
• Metallurgical Testing: PFS‑level testing to commence late Q4 2025; completion targeted Q2 2026.
• Pre‑Feasibility Study (PFS): Targeted completion of PFS on North Island Project by Q4 2026.
• Regional Exploration – Stream Sediment Phase I: 79 heavy mineral concentrate, 74 silt, and 9 moss mat samples collected; results show strong Cu anomalies near known deposits and new prospective areas to the east. Phase II commencing soon.
• 3‑D Geological Modeling: Initial Jurassic pluton model completed with Mira Geoscience Ltd.; further structural integration planned.
• Financing: Completed C$39.5 million financing (August 2025).
• Milestones Completed: Updated Preliminary Economic Assessment, Phase V exploration start, BC Hydro conceptual interconnection review, COO hire, baseline study commencement, etc.
• Upcoming Investor Events (2025‑2026): Gentile European Mining Tour (Oct 6‑10 2025), Swiss Mining Institute (Nov 19‑21 2025), Vancouver Resource Investment Conference (Jan 25‑26 2026), AME Roundup (Jan 26‑29 2026), TD Securities Mining Conference (Jan 27‑20 2026).
• Qualified Person: Dr. Pablo Mejia Herrera, P.Geo., VP Exploration, reviewed and approved technical disclosure.

Notable Quotes

“Upon completion of our financing in August, our team has been hard at work to execute against our vision of unlocking the potential of our 35 km porphyry district as quickly as possible… We are continuing to work in earnest with our First Nations, Provincial, and Federal Governments to ensure the swift realization of this generational opportunity for all rights holders and stakeholders.” – Sam Lee, President & CEO

Materiality Assessment: Material – Positive (significant expansion of drilling program, large financing, multiple project milestones, and forward‑looking schedule toward a pre‑feasibility study.)