T homas "Tom" Steyer is an American billionaire hedge fund manager who has become one of the most prominent and influential philanthropists and political activists in the United States. He began his finance career at Goldman Sachs and, in 1986, founded the hedge fund Farallon Capital Management. He built Farallon into one of the largest and most successful hedge funds in the world, with a multi-strategy, event-driven investment approach that made him a multi-billionaire.

In 2012, Steyer retired from his firm to dedicate his time and fortune to philanthropy and political and environmental advocacy. He has since become one of the largest financial donors to the Democratic party and to causes related to combating climate change. He founded the non-profit organization NextGen America, which is focused on mobilizing young voters around progressive issues like climate, healthcare, and immigration. In 2020, he spent over $300 million of his own money on an unsuccessful bid for the Democratic nomination for President of the United States. He and his wife have signed the Giving Pledge.