The Greatest Fund Ever? Why Jim Simons' Medallion Fund Keeps Winning Without Him

The article revisits Jim Simons’ Medallion Fund and argues it has delivered exceptional performance even after Simons stepped away from day-to-day management. It contrasts long-run returns at Renaissance Technologies’ flagship strategy with well-known investors such as Warren Buffett, whose Berkshire Hathaway posted average annual returns of about 20% over roughly six decades. The core comparison is durability: the article notes that sustaining market-beating returns for 60 years is rare, positioning Medallion as an outlier. Renaissance data cited estimates the Medallion Fund generated a 39.9% compound annual growth rate since its March 1988 launch after fees, and 66.1% before fees.

The piece also describes Medallion’s unusually high fee structure, noting it charged more than typical hedge funds’ standard 2% management fee and 20% performance fee, yet still produced nearly four decades without a losing year. Before Simons reduced involvement in 2010, the fund generated about 38.5% net annual returns and 62% gross returns. Afterward, net returns stayed around 39% annually while gross returns increased into a 75% to 80% range. It attributes ongoing success to a strategy designed to evolve, including changes in algorithms and expansion into alternative datasets such as machine learning models and text analysis, as markets shifted with social media volatility and crowded traditional signals.