They're a huge outsource/offshore company as well. Nasty business.
By definition, any major petroleum company have major offshore operations--in many cases, quite literally! For example, BP (formerly British Petroleum) owns ARCO and has huge investments in oilfields in Alaska and the Gulf of Mexico--and BP is one of the "smaller" petroleum multinationals compared to bigger ones like Exxon Mobil, Royal Dutch Shell, Chevron, TotalFinaElf, etc.
You kind of have to be if you want to pump much oil.