In the second-largest award ever from a World Bank arbitration tribunal, litigators from Debevoise & Plimpton won nearly $6 billion for mining company Tethyan Copper Co. in a dispute with the Islamic Republic of Pakistan.

The fight involves the Reko Diq mine—a vast and undeveloped deposit of copper and gold in Pakistan's remote province of Balochistan.

Starting in 2006, Tethyan—a joint venture between Antofagasta plc and Barrick Gold Corp.—struck a deal with the province to develop the mine, spending a reported $220 million on extensive exploration and feasibility work.

But in 2011, according to Debevoise, the province with Pakistan's assistance ousted their client from the Reko Diq mine so that it could do the project itself.

The International Centre for Settlement of Investment Disputes panel previously found that Pakistan wrongly denied Tethyan Copper a lease to the mine, breaching multiple treaty obligations regarding fair and equitable treatment, expropriation, and non-impairment.

Now, the ICSID panel slapped the country with more than $4 billion in damages, plus about $1.8 billion in pre-award interest, and $62 million in costs.

“We are enormously pleased with this result,” said Debevoise partner Donald Francis Donovan in a written statement. “It reflects not only the extraordinary lawyering of our team, including partners Mark Friedman, Dietmar Prager, and Natalie Reid, but the commitment of [Tethyan Copper] and its owners, including board, management, and senior internal counsel, in a true collaboration over the course of these proceedings.”

He added that “The decisions at every stage, and the magnitude of the eventual award, all vindicate our strategy, affirm the integrity of TCC's claims, and uphold the rule of law at the international level.”

Still, don't expect the dispute to end with Pakistan simply writing a $6 billion check. According to Reuters, Tethyan Copper after the ruling expressed willingness to reach a negotiated settlement. The office of Pakistan's attorney general responded that it “welcomes this approach to work towards a mutually beneficial solution that works for both sides.” 

The office added that “Pakistan is a responsible state and the Government of Pakistan takes its international legal obligations most seriously.”

Pakistan was represented by Washington, D.C. and Miami-based international dispute boutique GST, as well as Axis Law Chambers in Lahore, Pakistan; URJ & Co in Lahore, Pakistan and the Office of the Attorney General for Pakistan.