Osisko intercepts 256 m averaging 0.85% Cu at Gaspé

Includes 28.5 Metres Averaging 4.74% Cu and 27.4 g/t Ag

MONTREAL, Sept. 10, 2026 (GLOBE NEWSWIRE) -- Osisko Metals Incorporated (the “ Company ” or “ Osisko Metals ”) ( TSX: OM ; OTCQX: OMZNF ; FRANKFURT: 0B51 ) is pleased to announce additional new analytical results from the 2026 drill program at the Gaspé Copper Project, located in the Gaspé Peninsula of Eastern Québec.

New results are presented below ( see Table 1 ), including 28 mineralized intercepts from 12 drill holes. Reported “infill” intercepts are located within the 2026 MRE model ( see April 14, 2026 news release ), focused on upgrading Inferred Mineral Resources to Measured or Indicated categories, as applicable. “Expansion” intercepts are located outside the 2026 MRE model and comprise either i) in-pit expansion, which offers potential to convert in-pit waste into additional resources within the 2026 MRE Whittle pit; or ii) out-of-pit expansion, consisting of mineralization located outside the 2026 MRE Whittle pit, which may potentially lead to the definition of new resources. Some of the reported intercepts may have contiguous shallower infill as well as deeper expansion (noted as “Both”). Maps showing hole locations are available at www.osiskometals.com .

Osisko Metals Chief Executive Officer Robert Wares commented: “We are very pleased with these excellent new results from the current drilling, particularly the high-grade intercept in hole 30-1228 located 800 metres west of the 2026 MRE model. The mineralized system continues to expand beyond the current pit limits with noticeable grade improvement in the area around Needle Mountain. Additionally, infill holes 30-1233 and 30-1235 produced better-than-average grades at the south end of the 2026 MRE model. New assay results are now being received at a faster pace, and we expect to provide continuous updates throughout the fall.”

Highlights

256.5 metres averaging 0.85% Cu (Out-of-p