When most people think of legendary hedge fund managers, they picture Wall Street veterans with decades of trading experience. But the most successful quantitative fund in history was built by a retired math professor who didn’t enter finance until he was 40 years old.
This is the story of how Jim Simons and his team of scientists created returns so extraordinary that they eventually stopped accepting outside money.
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Fund That Defied Belief
This fund made so much money, they had to start giving it back. Not to investors—to themselves. Because external investors weren’t even allowed anymore.
Why? Because Medallion, the flagship fund at Renaissance Technologies, was compounding at over 66% annual returns before fees. For decades.
Let that sink in. Wall Street thought it was a myth. But it was real.
The Unconventional Founder
It was built by a retired math professor named Jim Simons—not a banker, not a trader, not a finance guy. The craziest part? Jim Simons didn’t start Renaissance until he was 40 years old.
A Different Approach
He hired physicists, codebreakers, astronomers—people who didn’t think like Wall Street. They didn’t guess. They didn’t bet on vibes. They let the data speak. And it didn’t whisper—it screamed alpha.
The Numbers
In the 2000s, Medallion made more profit in one year than most funds make in a decade. Over 40% of Renaissance staff held PhDs. Simons eventually closed the fund to outsiders so his employees could keep the profits.
While others pitched vision, they printed returns.
The craziest part? Jim Simons didn’t start Renaissance until he was 40 years old.
The Medallion Fund stands as perhaps the greatest example of what’s possible when you replace Wall Street’s traditional approach with pure scientific rigor.