ConocoPhillips Co. added Al Walker, former chairman and CEO of Anadarko Petroleum, to its board of directors, the Houston-based company said in a news release earlier this week.

Walker joins the ConocoPhillips board nearly a year after Anadarko agreed to be acquired by Chevron Corp., which set off a multibillion-dollar takeover battle for The Woodlands, Texas-based independent between the oil major and Occidental Petroleum Corp.

Occidental Petroleum ultimately won out with a sweetened offer that included an up to $10 billion investment from Warren Buffet’s Berkshire Hathaway Inc. Anadarko’s sale to Occidental closed August 2019.

Walker, who had served as CEO of Anadarko since 2012 after joining the company in 2005, also currently serves on the boards of BOK Financial Corp. and Health Care Services Corp. He is vice chairman and a member of the executive committee of the Business Council, and is chairman of the board of trustees of the Houston Museum of Natural Science.

In addition to Walker, ConocoPhillips also added David T. Seaton, the previous head of Fluor Corp., as a director on its board, according to the March 3 release.

The election of Walker and Seaton increases the number of ConocoPhillips directors to 13, of which 12 are independent.

Walker and Seaton will serve on the public policy committee and audit and finance committee of the ConocoPhillips board.