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Jim Simons, the renowned quantitative hedge fund manager and mathematician, has died aged 86, according to a statement from his family foundation.

Known as the “quant king”, Simons was a pioneer of quantitative investing, which uses large amounts of market data and computer algorithms to drive trading decisions. He left his mark on the industry with the hugely profitable hedge fund Renaissance Technologies, which he founded in 1982.

Simons relinquished the day-to-day management of Renaissance in 2010. In early 2021, he stepped back from his role as co-chair of the fund and from his family’s Simons Foundation, which sponsors research in mathematics and basic sciences.

“Jim was an exceptional leader who did transformative work in mathematics and developed a world-leading investment company,” Simons Foundation president David Spergel said on Friday when announcing the investor’s death.

Simons was born in Massachusetts in 1938, and liked mathematics from an early age, according to his foundation. He graduated with an undergraduate degree in the subject from MIT in 1958, before getting his doctorate from the University of California, Berkeley in 1961.

Simons worked as a Cold War codebreaker for the US National Security Agency during the mid-1960s, before moving to Stony Brook University later in the decade where he chaired the maths department at the New York-based school.

His academic work with a colleague in the 1970s contributed to the development of knowledge in string theory, quantum field theory and condensed matter physics, according to his foundation.

Simons left academia and in 1978 founded a hedge fund which drew on his mathematical expertise. Renamed Renaissance Technologies in 1982, the business was a pioneer of quantitative trading strategies that paid off famously for its flagship Medallion Fund.

The firm was known for its focus on hiring trained mathematicians, and has about 300 employees with 90 PhDs between them, according to its website.

The flagship Medallion fund ejected external investors in 2005, only allowing investment from its own employees. The secretive firm expanded its assets by tens of billions of dollars over the years, managing $60bn in 2021.

Quantitative investing has become one of the hottest parts of the hedge fund industry for investors, with funds such as DE Shaw, AQR, Two Sigma and others following in Renaissance’s footsteps.

There was some turbulence during the fund’s history, including in 2021 when Simons and other executives at Renaissance agreed to pay about $7bn in back taxes and penalties to US federal authorities to end a dispute over trades made by the flagship fund.

After stepping back from executive responsibilities at his fund, Simons spent more time at the foundation he co-founded with his wife Marilyn in 1994. The Simons Foundation has provided funding in life and physical sciences, autism research, mathematics and other areas, with several grant recipients going on to win Nobel Prizes. Its latest annual report for 2022 put the foundation’s assets at almost $5bn.

Simons is survived by his wife, three children, five grandchildren and a great-grandchild, according to his foundation.

Simons summed up his career at a 2022 event organised by the Abel Prize for mathematics: “I did a lot of math, I made a lot of money, and I gave almost all of it away.”