Ranked by Forbes as the 83rd richest billionaire in the world, James Simons is known as the founder of Renaissance Technologies with an estimated net worth amounting to $16.7 billion in May 2019. James Harris Simons is actually a mathematician, a successful hedge fund manager and a well known philanthropist.

Renaissance Technologies is a private investment firm which is currently based in New York. It is considered as the most successful hedge funds in the world. He was the company's CEO until his retirement in 2009.

Born and raised in Massachusetts, James Simons came from a Jewish family. He attended  Massachusetts Institute of Technology  where he finished his bachelor's degree on Mathematics. He obtained his PhD at the University of California, Berkeley 3 years later.

After graduation, he worked as a research staff at Institute for Defense Analyses. Later on, he was hired to teach mathematics at Harvard University and Massachusetts Institute of Technology. In 1978, he decided to leave the academe to pursue a career on managing hedge funds.

He then established the Renaissance Technologies' hedge funds. The company employs mathematical models to execute and analyze trades, wherein most of which are automated. In 2006, he was named by the International Association of Financial Engineers as Financial Engineer of the Year. On the same year, he was named as the World's Smartest Billionaire by the Financial Times. By that time, he was already earning $1.7 billion annually. In 2004, he earned $670 million, $1.5 billion in 2005 and in 2007, he earned a total of $2.8 billion.

Currently, James Harris Simons lives in Long Island and Manhattan with his wife, Barbara.  He has five children but two of them died at an early age due to an auto accident and drowning.