Britain's top court has refused to hear United Company Rusal's challenge to a London Metal Exchange plan to ease delivery backlogs at warehouses.
The Supreme Court's decision effectively ends Rusal's lawsuit over the proposed rules, which the Russian company said were unfairly implemented and would cost it tens of millions of pounds.
"The application does not raise an arguable point of law," the court said in a statement.
The world's largest metals exchange, which is owned by Hong Kong Exchanges and Clearing, decided to change its rules last year to reduce waiting times for stockpiles held in its network of warehouses. It postponed the plans because of Rusal's lawsuit.
"The LME has a duty to ensure the integrity of its reference prices and the operation of a fair and liquid market for all industry participants," the exchange said in a statement. The new rules will come into force in February, it said.
Rusal said that while it was disappointed with the court's decision, the rule change was likely to have little effect on queues.