[2] In addition to exploration and production, the company engaged in petroleum and natural gas gathering, processing, treating, and transportation.

[3] Anadarko was formed in 1959 as a subsidiary of Panhandle Eastern Corporation Pipe Line Company after the discovery of large amounts of natural gas in the Anadarko Basin, which underlies the western part of the state of Oklahoma and the Texas Panhandle, and extending into southwestern Kansas and southeastern Colorado.

[17] In December 2008, the company sold its 50% interest in the Peregrino heavy oil field offshore Brazil to Statoil for $1.4 billion.

[25] In January 2017, the company sold its assets in the Eagle Ford to Sanchez Energy and The Blackstone Group for $2.3 billion.

[29][30][31] In December 2016, Anadarko was ranked as among the 14th best of 92 oil, gas, and mining companies on indigenous rights and resource extraction in the Arctic by the Norwegian Institute of International Affairs.

In early 2010, BP billed Anadarko more than $272 million as a partial payment for its share of cleanup and response costs in the Gulf.

[34] In May 2011, MOEX Offshore, a subsidiary of Mitsui and owner of a 10% non-operating ownership interest in the Macondo Prospect, settled claims with BP for $1.07 billion.

[36][37] In December 2015, U.S. District Judge Carl Barbier ordered Anadarko to pay a civil fine under the Clean Water Act of $159.5 million, or $50 per barrel of oil spilled as a result of the Deepwater Horizon explosion.

Barbier wrote that the $159.5 million fine "strikes the appropriate balance between Anadarko's lack of culpability and the extreme seriousness of this spill.

"[33] The fine came after BP and Anadarko had unsuccessfully appealed to the Supreme Court of the United States to reject Judge Carl Barbier's finding of negligence in the Deepwater Horizon accident.

As background, in 2006, Kerr-McGee spun off its Tronox subsidiary to offload 70 years of environmental dumping of toxic waste across 22 states beginning in the 1920s.

The environmental damages included polluting Lake Mead in Nevada with rocket fuel, leaving behind radioactive waste piles throughout the territory of the Navajo Nation and dumping carcinogenic creosote in communities throughout the East, Midwest and South at its wood-treating facilities.