Tom Steyer

American billionaire and hedge fund manager Tom Steyer built his fortune through the investment firm Farallon Capital he founded in 1986. Over time the company has grown to the point where it manages $20 billion in assets. He stepped away from the helm in 2012 to focus on advocacy for alternative energy, launching NextGen America, an environmental advocacy nonprofit organization that is heavily involved in campaigning on climate change issues. Steyer even personally divested all of his carbon-polluting investments, although some note that the companies Farallon helped with financing during his tenure went on to greatly increase their carbon emissions, and that he extended their lifespans. Still, he’s on the right side of the fight now.

Location: San Francisco

Age: 60

Twitter: @TomSteyer