By market cap (or enterprise value), Apple's the largest public company now, worth about $700b, which is about 2x as much as the next biggest (Exxon, Microsoft,

By market cap (or enterprise value), Apple's the largest public company now, worth about $700b, which is about 2x as much as the next biggest (Exxon, Microsoft, etc.). Although Saudi Aramco is probably the world's most valuable company if non-publicly-traded companies are included.