ExxonMobil, the world’s largest and most powerful oil company, knew everything there was to know about climate change by the mid-1980s, and then spent the next few decades systematically funding climate denial and lying about the state of the science.”

http://www.thenation.com/article/exxon-knew-everything-there-was-to-know-about-climate-change-by-the-mid-1980s-and-denied-it/