In 1933, Saudi Arabia granted California Standard a concession to find oil, which led to the discovery of oil in 1938. In 1948, California Standard discovered the world's largest oil field in Saudi Arabia, Ghawar Field. California Standard's subsidiary, California-Arabian Standard Oil Company, grew over the years and became the Arabian American Oil Company (ARAMCO) in 1944. In 1973, the Saudi government began buying into ARAMCO. By 1980, the company was entirely owned by the Saudis, and in 1988, its name was changed to Saudi Arabian Oil Company—Saudi Aramco.