"These court decisions are the product of rank corruption and are a black mark on the judicial system of Mexico," president and CEO Brendan Cahill said.

"The value ascribed in the judgment is impossible based on evidence, facts or law."

The dispute had escalated in 2019, after the owner of a concession within Excellon's Evolucion property sued San Pedro for failing to adhere to a 2006 exploration and exploitation agreement, specifically for not restarting Miguel Auza, which was mothballed before Excellon's acquisition in 2009.

The initial $700,000 in damages had been increased to $23 million on appeal in the district court.

Excellon said yesterday it had received the formal written decision on San Pedro's appeal to the federal court, which appeared to uphold the judgment granting the plaintiff $23 million and was not subject to further legal appeal in Mexico.

"We continue to pursue avenues through our labour, community and government relationships and are investigating remedies under international law," Cahill said.

Eric Sprott-backed Excellon said San Pedro, which employed about 90 people, continued to operate.

It generated "minimal cash flows" from milling fees charged to Excellon's flagship Platosa mine, operated by a separate subsidiary.

San Pedro's fixed assets had a book value of $4.8 million, Excellon said.

It said the subsidiary held the Miguel Auza processing facility and the original Miguel Auza mineral concessions, including the Evolucion mineral resource disclosed in September.

The company believed the plaintiff had no recourse against Excellon's other assets in Mexico, Idaho, Germany or Canada.

Excellon had $6.6 million in working capital at June 30.

Its shares (TSX: EXN) returned towards a one-year low yesterday, closing down 9.1% to C$2.39, valuing it at $78.3 million (US$62.5 million).