Saudi Aramco is the world's largest publicly traded oil company by proven crude-oil reserves.
Saudi Aramco, formally the Saudi Arabian Oil Company, operates the world's largest integrated petroleum system and controls the vast majority of Saudi Arabia's hydrocarbon resources. Its crude-oil reserves are far larger than those of most publicly traded international oil majors.
The company was created from the former Arabian American Oil Company and became fully owned by the Saudi government in 1980. A portion of its shares was listed on the Saudi Exchange in 2019, giving public investors access to a minority stake while the state retained control.
Reserve rankings, daily production rankings, revenue rankings, and market-cap rankings are different measures. Saudi Aramco can lead one measure without leading every other category. Its huge reserves and earnings have nevertheless made it a recurring member of global market-cap rankings.