The US treasury department fined Exxon Mobil $2,000,000 for violating government sanctions against Russia in 2014. Trump’s Secretary of State Rex Tillerson was CEO of Exxon Mobil at the time.
The heads of the company's U.S. subsidiaries signed eight documents between May 14 and May 23, 2014 with Igor Sechin, the head of Russia's largest oil producer, Rosneft, Treasury's Office of Foreign Assets Control said in a statement on its website.
Sechin had been blacklisted by the United States just weeks earlier.
The Treasury unit, which enforces sanctions, found ExxonMobil had not voluntarily self-disclosed the violations, "and that the violations constitute an egregious case."
Reuters got a quote from an Exxon Mobil spokesperson which I will paraphrase for you: Exxon Mobil had considered their dealings a loophole and they are totally annoyed that they're getting called out for it now.
According to Exxon Mobil, in 2015 they earned $16.2 billion. To put that into perspective, in 2015 the National Wage Index in the United States was $48,098.63. A $2,000,000 fine is the equivalent of forcing the average wage earner in the United States, in 2015, to fork over $5.94.