In 2008, the year the S&P 500 lost 36.6% with dividends reinvested, the Medallion Fund made 7.9 billion dollars of trading profit on 5.2 billion dollars of capital. That is a gross return of 152%. After fees its investors kept about 82% to 83%.
Medallion is the private fund that Renaissance Technologies runs for its own employees. From 1988 to 2018 its gross return averaged 66.0% a year and its net return 39.2%, against 11.5% for the S&P 500. It lost money in one year out of 31. Trading profits over those 31 years add up to 104.5 billion dollars.
The fund publishes nothing. The yearly figures below are Medallion's own numbers as printed in the appendix of The Man Who Solved the Market, Gregory Zuckerman's 2019 biography of Jim Simons. Only a handful of later years have reached the press.
Medallion Fund returns by year, 1988 to 2018
Capital is what the fund held at the start of the year and trading profit is before fees, both in millions of dollars. Gross return is profit divided by capital. Net return is what investors kept after fees.
| Year | Capital at start | Trading profit | Gross return | Net return | S&P 500 with dividends |
|---|---|---|---|---|---|
| 1988 | 20 | 3 | 15.0% | 9.0% | 16.5% |
| 1989 | 20 | 0 | 0.0% | -3.2% | 31.5% |
| 1990 | 30 | 23 | 76.7% | 58.2% | -3.1% |
| 1991 | 42 | 23 | 54.8% | 39.4% | 30.2% |
| 1992 | 74 | 35 | 47.3% | 33.6% | 7.5% |
| 1993 | 122 | 66 | 54.1% | 39.1% | 10.0% |
| 1994 | 276 | 258 | 93.5% | 70.7% | 1.3% |
| 1995 | 462 | 244 | 52.8% | 38.3% | 37.2% |
| 1996 | 637 | 283 | 44.4% | 31.5% | 22.7% |
| 1997 | 829 | 261 | 31.5% | 21.2% | 33.1% |
| 1998 | 1,100 | 628 | 57.1% | 41.7% | 28.3% |
| 1999 | 1,540 | 549 | 35.6% | 24.5% | 20.9% |
| 2000 | 1,900 | 2,434 | 128.1% | 98.5% | -9.0% |
| 2001 | 3,800 | 2,149 | 56.6% | 33.0% | -11.9% |
| 2002 | 5,240 | 2,676 | 51.1% | 25.8% | -22.0% |
| 2003 | 5,090 | 2,245 | 44.1% | 21.9% | 28.4% |
| 2004 | 5,200 | 2,572 | 49.5% | 24.9% | 10.7% |
| 2005 | 5,200 | 2,999 | 57.7% | 29.5% | 4.8% |
| 2006 | 5,200 | 4,374 | 84.1% | 44.3% | 15.6% |
| 2007 | 5,200 | 7,104 | 136.6% | 73.4% | 5.5% |
| 2008 | 5,200 | 7,911 | 152.1% | 83.4% | -36.6% |
| 2009 | 5,200 | 3,881 | 74.6% | 39.0% | 25.9% |
| 2010 | 10,000 | 5,750 | 57.5% | 29.4% | 14.8% |
| 2011 | 10,000 | 7,107 | 71.1% | 37.0% | 2.1% |
| 2012 | 10,000 | 5,679 | 56.8% | 29.0% | 15.9% |
| 2013 | 10,000 | 8,875 | 88.8% | 46.9% | 32.2% |
| 2014 | 9,500 | 7,125 | 75.0% | 39.2% | 13.5% |
| 2015 | 9,500 | 6,582 | 69.3% | 36.0% | 1.4% |
| 2016 | 9,500 | 6,514 | 68.6% | 35.6% | 11.8% |
| 2017 | 10,000 | 8,536 | 85.4% | 45.0% | 21.6% |
| 2018 | 10,000 | 7,643 | 76.4% | 40.0% | -4.2% |
Capital and trading profit are from Zuckerman's appendix as reproduced in Guo and Liu's 2024 paper. Net returns are the published figures compiled by Visual Capitalist, and S&P 500 returns come from Aswath Damodaran's data set at NYU Stern.
Two years carry other net figures elsewhere. Elwyn Berlekamp, who ran the trading company in 1990, gives that year as 55% after fees of 5% of assets and 20% of profits. For 2008, other compilations print 82%, which is what the fee formula below gives on a 152.1% gross return.
Average, compound and risk-adjusted returns
All of these come from the table above, except Cornell's figures.
- Average gross return: 66.0% a year
- The simple mean of the 31 gross returns, and the "66%" most often quoted for Medallion.
- Compound gross return: 63.2% a year
- The growth rate if every year's gross return had been reinvested. Bradford Cornell puts it at 63.3%, enough to turn 100 dollars into 398.7 million dollars by 2018.
- Average net return: 39.2% a year
- The mean after fees. The S&P 500 averaged 11.5% over the same 31 years.
- Compound net return: 37.9% a year
- At that rate 100 dollars becomes 2.1 million dollars by the end of 2018. The S&P 500 with dividends compounded at 10.1% and turned 100 dollars into 1,968 dollars.
- Volatility and Sharpe ratio
- Net returns had a standard deviation of 20.4% a year, against 17.0% for the index. With 3-month Treasury bills averaging 3.1%, that gives a Sharpe ratio of 1.77 on annual data, against 0.49 for the S&P 500.
- Link to the stock market
- The correlation between Medallion's net returns and the S&P 500 was -0.49. The fund made money in all six years the index fell: 1990, 2000, 2001, 2002, 2008 and 2018. Cornell found its market beta and its loadings on the standard risk factors were all negative, so the returns cannot be read as payment for carrying market risk.
Medallion returns since 2019
After 2018 the record has gaps. Renaissance does not comment on Medallion, and the figures that exist come from people who have seen investor statements.
| Year | Medallion | S&P 500 with dividends |
|---|---|---|
| 2019 | Not published | 31.2% |
| 2020 | 76% | 18.0% |
| 2021 | Not published (9.7% in the first quarter) | 28.5% |
| 2022 | Not published | -18.0% |
| 2023 | Not published | 26.1% |
| 2024 | 30% | 24.9% |
| 2025 | Not published | 17.8% |
Medallion gained 76% in 2020 while Renaissance's two main outside funds lost more than 20%. It added 9.7% in the first quarter of 2021. In 2024 it returned 30% on about 12 billion dollars of capital.
No figure for 2025 has been published. In October 2025 Renaissance's two outside funds lost 14.4% and 15.6%, which left RIEF down 7.5% and RIDA down 10.3% for the year.
Medallion's fees, from 5% and 44% to 4% and 36% to 44%
Medallion charges roughly double the "2 and 20" long associated with hedge funds, whose mechanics are covered in our guide to hedge fund fees. In 1990 the fee was 5% of assets and 20% of profits. The published net returns fit that 5% fee with an incentive fee of 20% through 2000, 36% in 2001 and 44% from 2002. From 1994 to 2018 the formula matches the published figure to within a tenth of a point in 23 of 25 years, and misses by 0.3 points in 2007 and 1.0 point in 2008.
Net return from gross return
Net return = (gross return − 5%) × (1 − incentive fee)
2018: (76.4% − 5%) × (1 − 0.44) = 40.0%, the published figure.
On those terms, fees took about 48.7 billion dollars of the 104.5 billion dollars of trading profit from 1988 to 2018, close to half. That estimate applies each year's fee to start-of-year capital. Since 2005 the investors have been Renaissance's own people, so the fee moves money from the fund's investors to the firm's owners, and the two groups overlap heavily.
The fee has since come down. Renaissance's brochure dated March 30, 2026 sets Medallion's management fee at 4% a year of each investor's capital account, paid monthly in advance, and the performance allocation at 36% to 44% of net profits, taken every six months. Losses must be recouped before the next allocation. The brochure does not say when the management fee fell from 5% to 4%.
Why the compound figures overstate what investors earned
The 2.1 million dollars that 100 dollars would have become assumes every dollar of profit stayed in the fund. Medallion pays its profits out instead and keeps its capital near a ceiling: about 5.2 billion dollars from 2002 to 2009 and about 10 billion dollars from 2010 to 2018.
A two-year example shows the effect. Cap a fund at 100 dollars and let it earn 50% in each year, paying the profit out at the end of each year. The investor ends with the original 100 dollars plus two payouts of 50, or 200 dollars. That is 41.4% a year. Chaining the two yearly returns gives 50% a year and 225 dollars, which nobody received. Over ten years at 50%, the payout version compounds at 19.6% a year.
Shuxin Guo and Qiang Liu applied that logic to Medallion's capital and profits. Their estimate of the compound return before fees from 1988 to 2018 is 31.8% a year, against the 63% reported by Zuckerman and Cornell. Split in two, it was 51.8% from 1988 to 2001, while capital was still growing, and 19.1% from 2002 to 2018, once it was capped. The method ignores what payouts earn once they leave the fund and can misallocate profit in years when new money came in, so the authors give a range: probably under 35% a year.
The yearly returns themselves are unaffected. Each one is profit divided by the capital at risk that year.
How big the Medallion Fund is
Medallion started in 1988 with 20 million dollars. Capital was 1.1 billion dollars at the start of 1998, was held around 5.2 billion dollars from 2002 to 2009 and around 10 billion dollars from 2010. It was about 12 billion dollars in 2024.
The fund is a master-feeder structure. Four feeder funds, Medallion Fund L.P., Medallion Associates L.P. and Medallion USA L.P. in Delaware and Medallion International Ltd. in Bermuda, invest in a master fund, Medallion Holdings LLC. Renaissance's Form ADV, as amended on July 1, 2026, reports for that master fund:
- a gross asset value of 61.2 billion dollars, up from 34.8 billion dollars of regulatory assets at the end of 2020
- about 549 beneficial owners
- 80% of the fund owned by Renaissance and its related persons, and 1% by people outside the United States
- a minimum investment of 25,000 dollars
- PricewaterhouseCoopers as auditor
Gross assets count positions bought with borrowed money. If capital is still near the 12 billion dollars of 2024, 61.2 billion dollars is roughly five dollars of assets for each dollar of the fund's own money, before derivatives. The whole firm reported 96.4 billion dollars of regulatory assets under management and 310 employees in the same filing.
Closed to outside investors since 1993
Medallion stopped accepting new outside money in 1993 and bought out its remaining outside investors in 2005. Since then it has been open to current and former employees and a few people with long ties to the firm. Wealth or status does not change that: an accredited investor or a pension fund cannot buy in.
The cap reflects capacity. Short-term trading signals can absorb only so much money before the fund's own trades move prices against it, so extra capital would dilute returns. Paying out profits keeps the fund at the size its models can trade.
Outside investors have Renaissance's institutional funds, covered below, and other quantitative firms on our list of notable hedge funds.
What is publicly known about how Medallion trades
Medallion runs a short-term quantitative strategy across several asset classes. The most detailed public record of how it trades comes from a 2014 Senate investigation into the "basket options" the fund bought from Barclays and Deutsche Bank. The hearing record shows:
- Volume. More than 100,000 trades a day through the option accounts, about 30 million a year, with about 87% of the portfolio turning over every three months.
- Horizon. Positions based on mispricings that last days or weeks, found by models that researchers keep adjusting. The firm then had 200 to 250 employees, about 90 of them with PhDs in mathematics or science.
- Leverage. In the option accounts the fund put up 10% of the cash and the bank lent the rest. Leverage reached as high as 20 to 1, against the 2 to 1 limit of an ordinary brokerage account.
- Profit. More than 30 billion dollars of Medallion's profit from 1999 to 2013 came through these accounts.
- Tax. Held inside an option for more than a year, short-term trading gains were reported as long-term capital gains. The subcommittee chairman put the tax saved at about 6.8 billion dollars.
In 2021 Renaissance's executives agreed to settle the dispute with the IRS for as much as 7 billion dollars, covering Medallion trades from 2005 to 2015, and Simons agreed to pay a further 670 million dollars.
In the late 1980s Medallion's trading was run by Axcom, a small company whose only business was building computer-based systematic strategies for the fund. Performance fell apart in 1989. Elwyn Berlekamp, a Berkeley mathematician who had consulted for Axcom since 1986, bought its largest share, moved the team to Berkeley and restarted trading late in 1989. Sixteen months later he sold out to Simons at six times what he had paid.
Renaissance's quarterly 13F filings list the firm's long US stock positions across all its funds. They leave out short positions, futures and most derivatives and do not separate Medallion from RIEF and RIDA, so they show little of what Medallion holds on a given day.
Cornell calls Medallion the ultimate counterexample to the efficient market hypothesis and finds no adequate rational market explanation for a 31-year record with one losing year and negative market exposure. Its models look for price patterns that depart from a random walk for days or weeks. Renaissance staffs its research with mathematicians, physicists and computer scientists who model prices from data, an approach close to econophysics, which applies tools from statistical physics to markets.
Jim Simons and the people who run Renaissance
Jim Simons founded the firm in 1978, after a career as a mathematician that included the 1974 paper with Shiing-Shen Chern behind the Chern-Simons forms used in theoretical physics, and years as chair of the mathematics department at Stony Brook. Our guide on how to become a hedge fund manager covers how unusual his route into finance was. He died on May 10, 2024, at 86.
He had handed over the running of the firm years earlier. In 2010 he made Peter Brown and Robert Mercer co-chief executives and retired, and Mercer announced his resignation in November 2017. The 2026 Form ADV lists:
- Peter Brown as chairman, co-president and co-chief executive.
- David Lippe as director, co-president and co-chief executive.
- Henry Laufer as a director since 1996.
- The estate of James H. Simons as owner of between 25% and 50% of the holding company that owns Renaissance.
The only full-year Medallion figure published since Simons's death is 30% for 2024.
RIEF and RIDA compared with Medallion
Outside investors can use two funds: the Renaissance Institutional Equities Fund (RIEF), launched in July 2005, and Renaissance Institutional Diversified Alpha (RIDA). RIEF is a long-biased stock strategy that aims to beat the S&P 500 with a beta of 0.4 or less and average leverage of about 2.5 to 1. RIDA trades stocks against a volatility target. Both ask outside investors for at least 5 million dollars.
| Year | Medallion | RIEF | RIDA | S&P 500 with dividends |
|---|---|---|---|---|
| 2020 | 76% | -22.6% | -33.6% | 18.0% |
| 2021 | Not published | 20.5% | Not published | 28.5% |
| 2024 | 30% | 22.7% | 15.6% | 24.9% |
| 2025 | Not published | -7.5% to October | -10.3% to October | 17.8% |
The 2020 RIEF and RIDA figures run to December 25. RIEF gained 20.5% in 2021, and in 2024 RIEF made 22.7%, its best year since 2011, and RIDA 15.6%. In October 2025 alone RIEF lost 14.4% and RIDA 15.6%.
The outside funds have shrunk. RIEF held just under 20 billion dollars in late 2025, down from nearly 36 billion dollars at the start of 2020, and RIDA about 2.8 billion dollars. In the 2026 Form ADV, RIEF Trading LLC, the master fund behind RIEF, reports 21.8 billion dollars of gross assets and 705 owners, and GF Trading LLC, the master fund for RIDA's feeders, 4.2 billion dollars and 193 owners. Medallion's master fund reports 61.2 billion dollars.
RIEF is built to carry market exposure, at a beta of up to 0.4, and to hold tens of billions of dollars. Medallion runs short-term strategies on capped capital and pays out what it cannot use. In 2020 the gap between the two was close to 100 percentage points.
Frequently asked questions
Can you invest in the Medallion Fund?
No. Medallion stopped taking new outside money in 1993 and bought out its last outside investors in 2005. Its roughly 549 investors are current and former Renaissance employees and people close to the firm, and Renaissance and its related persons own about 80% of it. Outside investors can only use Renaissance's other funds, RIEF and RIDA, which ask outside investors for at least 5 million dollars.
What is the average annual return of the Medallion Fund?
From 1988 to 2018 the gross return averaged 66.0% a year and the net return, after fees, averaged 39.2%. Compounded, the same yearly returns give 63.2% gross and 37.9% net. Because Medallion pays its profits out instead of reinvesting them, no investor's money actually compounded at those rates, and one estimate that accounts for the payouts puts the compound return before fees at 31.8% a year.
Has the Medallion Fund ever lost money?
Once, in 1989, when the net return was a loss of about 3% to 4% and the gross return was close to zero. Every other year from 1988 to 2018 was positive, including the six years the S&P 500 fell. No losing year has been reported since, although several years after 2018 have no published figure.
What did the Medallion Fund return in 2025?
No 2025 figure for Medallion has been published. Renaissance's outside funds lost 14.4% (RIEF) and 15.6% (RIDA) in October 2025, which left them down 7.5% and 10.3% for the year to the end of October. The S&P 500 returned 17.8% in 2025 with dividends.
How much money is in the Medallion Fund?
The fund's own capital has been held near 10 billion dollars since 2010 and was about 12 billion dollars in 2024, with profits above that level paid out to investors. Counting positions bought with borrowed money, Medallion Holdings LLC, the master fund, reported gross assets of 61.2 billion dollars in Renaissance's 2026 Form ADV.
Who runs Renaissance Technologies now?
Peter Brown is chairman, co-president and co-chief executive, and David Lippe is co-president and co-chief executive. Jim Simons, who founded the firm in 1978, made Brown and Robert Mercer co-chief executives in 2010 and retired. Mercer announced his resignation in November 2017. Simons died on May 10, 2024, and his estate holds between 25% and 50% of the company that owns Renaissance.