Phillips 66 PSX.N and activist investor Elliott Investment Management each won two seats on the oil refiner's board at an annual shareholders meeting on Wednesday, capping one of the biggest corporate boardroom battles of the year.

Phillips 66 shareholders are set to elect two of Elliott Investment Management’s nominees to its board, in the first ever US proxy vote for the activist investor.Most Read from BloombergCan Frank Gehry’s ‘Grand LA’ Make Downtown Feel Like a Neighborhood?

Elliott Investment Management, a Florida-based investor that has pushed UK supermajor BP to accelerate its oil and gas pivot, has won two seats on the board of Phillips 66 after a protracted management fight, the US refiner and chemical manufacturer said Wednesday.