ARCO

Atlantic Richfield Company (ARCO)
Company type	Private (subsidiary of Tesoro Corporation)
Headquarters	La Palma, California, United States
Number of locations	1,200
Area served	United States
Parent	British Petroleum (2000-2013); Tesoro Corporation (2013-present)
Website	ARCO.com

ARCO (short for Atlantic Richfield Company, the original name) is a United States oil company. It has operations^{n 2} in the United States, Indonesia, the North Sea, and the South China Sea.^[1] As of July 2011, it had more than 1,300 gas stations in the western part of the United States.^[2]

An ARCO filling station in Los Angeles, California

ARCO's original parent companies included:

Atlantic Petroleum, which opened its first gas station in 1915 in Pittsburgh, Pennsylvania.
Richfield Oil Company, which opened its first gas station in 1917 in Los Angeles, California.

The two companies merged in 1966, and bought Sinclair Oil Corporation in 1969. In 1978, ARCO opened its first ampm convenience store.

Between 1970 and 2000, ARCO had a complicated corporate history. By 1985, it sold its Eastern US business to a new Atlantic Petroleum. In 2000, the remaining Western US business was bought by British Petroleum (BP). Finally, in 2013,^[3] BP sold ARCO and the Carson Refinery to Tesoro for $2.5 billion.

Oil discovery

In 1957, Richfield was the first to drill for oil in Alaska.^[4] On July 15 of that year they struck oil with their first well. It was the first major oil discovery in Alaska and tested at 900 barrels a day.^[5] In 1968 they partnered with Exxon for Alaska North Slope oil production.^[6] In 1980, they were the seventh largest oil company in the United States.^[7]

ARCO Media

At one time, ARCO had its headquarters in what is now the City National Plaza complex in Downtown Los Angeles
An ARCO station in St. Clairsville, Ohio in 2021, well out of ARCO's traditional marketing territory and in the home state of Marathon.