At least three US oil companies were the target of a series of previously undisclosed cyberattacks that may have originated in China. Marathon Oil, ExxonMobil, and ConocoPhillips didnt realize the full extent of the attacks until the FBI alerted them in 2008. The attacks were focused on valuable bid data detailing the quantity, value, and location of oil discoveries worldwide. The data included e-mail passwords, messages, and other information tied to executives with access to proprietary exploration and discovery information.”]
Source: https://www.csmonitor.com/USA/2010/0125/US-oil-industry-hit-by-cyberattacks-Was-China-involved