Gold developer Seabridge Gold has removed one legal hurdle to its KSM project in British Columbia after Tudor Gold abandoned an appeal relating to the Mitchell Treaty Tunnels (MTT). The move resolves this specific challenge, but other hurdles remain. 

According to Seabridge, Tudor filed a notice of abandonment with the Supreme Court of British Columbia, ending its appeal of a 2025 decision by the Chief Gold Commissioner (CGC), who had declined jurisdiction over an application challenging the applicability of a conditional mineral reserve (CMR) linked to the tunnels.

The move effectively upholds the CGC’s earlier ruling.

The dispute centred on whether the CMR governing the MTT – a critical component linking the east and west sides of the project – should apply to mineral claims held by Tudor. About 12.5 km of the twin tunnels are expected to pass through claims owned by Tudor.

Under the CMR, claimholders are required not to obstruct, endanger or interfere with the construction, operation or maintenance of the tunnels.

Seabridge chairperson and CEO Rudi Fronk said the withdrawal confirmed the company’s position.

“We applaud Tudor's decision to abandon its appeal, which lacked any merit from the outset. This action reinforces our position that the authorisations issued in favour of the MTT do not give Seabridge any interest in Tudor's mineral rights.”

Seabridge noted that the legal effect of the CMR has been consistently supported by the British Columbia Ministry of Mines for more than a decade.

However, the abandoned appeal is only one element of a legal dispute between the parties.

In its 2026 strategy update, published on December 17, Tudor highlighted that it is advancing three proceedings in British Columbia courts relating to permitting overlap with Seabridge. These include the appeal of the CGC's jurisdictional decision on the CMR and tunnels, as well as a proceeding against the province of British Columbia regarding the scope of the CMR over the Treaty Creek claims and a judicial review of a licence of occupation granted to Seabridge.

Tudor previously proposed to shift 1 km northward the alignment of the 22-km tunnels that are intended to connect east and west sides of the KSM project. Tudor argued that about 12 km of the current tunnels would traverse its Treaty Creek claims, cutting through the Goldstorm deposit and piercing the under-explored Perfectstorm zone.

Tudor warned the tunnels plus an expected buffer zone would sterilise material ounces and constrain mine design and access, and it framed the modest increase in tunnelling –  about 2.5 km, or roughly a 3.1% rise in KSM’s pre-production excavations – as a small price to preserve the development optionality of a second major project in the region.