Chevron closed its $55 billion acquisition of Hess on Friday after winning a landmark legal battle against larger rival Exxon Mobil to gain access to the largest oil discovery in decades.

Arbitrators cleared the way for the long-delayed $53 billion acquisition after Exxon tried to pre-empt the deal.

Chevron struck the deal to acquire Hess in October 2023. Exxon tried to block the move last year, saying it had a right of first refusal to buy Hess’ Guyana assets because of its joint operating agreement with Hess and the China National Offshore Oil Corp., or Cnooc, for the Stabroek Block.