Skip to content
Yavqo
Billionaire Index

A daily ranking of the world's richest people

Last updated: November 11, 2026 · $11.70T tracked

Methodology

No. 63United States

Marilyn Simons & family

Hedge funds · East Setauket, New York

Net worth

$36.6B

Today

−$66−0.00%

Past month

+$100K+0.00%

As of Nov 11, 2026, 1:50 PM EST

Marilyn Simons is the widow of Jim Simons, the founder of quantitative hedge fund Renaissance Technologies, who died in 2024 at age 86. She got a Ph.D. in economics from Stony Brook University, where she met Jim. She chairs the $4.5 billion (assets) Simons Foundation, which is the primary funder of Math for America. Simons also sits on the boards of her alma mater Stony Brook University's foundation and Rockefeller University, and she chairs the board of Cold Spring Harbor Laboratory. The Simons family has given more than $10 billion to philanthropic causes including Math for America, autism research and Stony Brook.

Net worth over time

+0.00%+$100K over the past month
$37B$37B$37B
Oct 12Nov 11

Principal holdings

1 positions
CompanyShareValue

Private holdings

100.0%$36.6B