California Arabian Standard Oil Company (CASOC)

ASC is a wholly owned Saudi Aramco subsidiary that has been headquartered in Houston, Texas, since 1974. Its story dates back to 1950 with the establishment of a Delaware corporation with U.S. offices, just as the size and scale of Saudi Arabia’s energy reserves were being determined.

In 1933, Saudi Arabia signed a now historic Concession Agreement giving Standard Oil of California (Socal) permission to explore its country for oil. Socal’s wholly owned subsidiary, the California Arabian Standard Oil Company (CASOC) with headquarters in San Francisco, was assigned the task. To support this effort, The Texas Company (later Texaco) acquired half of CASOC in 1936, and in 1944, the enterprise was renamed the Arabian American Oil Company, or Aramco.

Standard Oil Company (later Exxon) and Socony-Vacuum Oil Company (later Mobil) became part owners in 1948 to help provide market outlets and capital investment for the immense hydrocarbon reserves of Saudi Arabia. Aramco’s headquarters moved from San Francisco to New York as part of the change in ownership.

The company maintained a number of Aramco offices in Los Angeles, Tulsa, Chicago and Washington, D.C., to carry out various recruiting, purchasing, shipping and other functions in support of the operations in Saudi Arabia.

In 1952, Aramco’s headquarters – including many officers and executive staff – moved to Dhahran, Saudi Arabia, and in 1980, the Saudi government completed its gradual buyout of Aramco’s assets. In 1988, the successor company was established as the Saudi Arabian Oil Company (Saudi Aramco).

Many of the duties of Aramco’s New York office were transferred to ASC when it was established in Houston in 1974.

Source: Saudi Aramco
http://www.aramcoservices.com/Who-We-Are/Our-History.aspx