Chevron Corp. has prevailed in a 20-month fight to buy Hess Corp. for $53 billion, overcoming a challenge by arch rival Exxon Mobil Corp. that was unprecedented in the modern history of Big Oil.

Chevron Corp. won its arbitration battle with Exxon Mobil Corp. and has closed its $53-billion deal to buy Hess Corp. more than 20 months after the takeover was announced.

The conclusion of the saga removes a stock overhang for Chevron and paved the way for the $53 billion deal to close immediately.