FILE - This April 23, 2018 file photo shows the logo for ExxonMobil above a trading post on the floor of the New York Stock Exchange. Massachusetts Attorney General Maura Healey has been methodically working on a case to find out what Exxon Mobil Corp. knew about the impact of burning fossil fuels _ and when. In January 2019, Healey inched closer to that goal when the U.S. Supreme Court refused to hear a bid by the company meant to block the investigation by the Massachusetts Democrat into whether the company misled investors and consumers about what it knew about the link between fossil fuels and climate change. (AP Photo/Richard Drew, File)