Jim Simons' Renaissance scored a 39% gain in its flagship Medallion fund as the coronavirus hammered rivals

• Jim Simons' Renaissance Technologies posted a 39% gain before fees at its flagship Medallion fund this year through April 14, The Wall Street Journal reported.
• The Cold War code-breaker's hedge fund scored almost a 10% gain in March, outperforming most of its rivals.
• However, Renaissance's equity fund lost 10% this year through April 10 as its computer models struggled to navigate volatile markets, Bloomberg reported.
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Renaissance Technologies, a secretive hedge fund founded by Cold War code-breaker and maths professor Jim Simons, scored a 39% gain in its flagship Medallion fund this year through April 14, The Wall Street Journal reported.

Medallion gained almost 10% in March, investors told The Journal. An estimated 75% of hedge funds posted losses that month as the coronavirus pandemic shook markets. Medallion's outperformance fueled a 24% gain after fees for the first 15 weeks of this year, The Journal reported.

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The Medallion fund — responsible for about $10 billion of Renaissance's $75 billion in assets under management — has delivered an average post-fees gain of 39% a year since 1988, The Journal said. It performed especially well during the dot-com crash in 2000 and the 2008 financial crisis, the newspaper added.

Renaissance's main equity fund lost 10% between January 1 and April 10, investors told The Journal. Some of its computer models failed to navigate roiling markets, Bloomberg said, citing a recent filing.

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Several other hedge funds capitalized on the coronavirus sell-off.

Bill Ackman's Pershing Square registered an 11% gain in March after scoring a $2.6 billion gain on credit-default swaps that offset losses in its equity portfolio.

Mark Spitznagel's "black swan" fund, Universa Investments, delivered a return of more than 4,000% in the first quarter, according to a client letter obtained by Business Insider.

Ruffer, a fund nicknamed "50 Cent," made a gain of $2.6 billion last quarter by betting on volatility and declines in equities, credit, and gold prices, offsetting its losses elsewhere.

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