Trading

How Did Jim Simons’s firm make $100bn? He told his secrets to our reporter

The huge gains came both from groundbreaking insights and lots of small innovations. Being way out on Long Island didn’t hurt either.

‘I’m not sure we’re the best at trading,’ Jim Simons, shown in 2007, once told a colleague. ‘But we’re the best at estimating the cost of our trades.’
‘I’m not sure we’re the best at trading,’ Jim Simons, shown in 2007, once told a colleague. ‘But we’re the best at estimating the cost of our trades.’ Photo: ASSOCIATED PRESS

How did Jim Simons do it?

I spent two years researching a book about Simons and his firm, Renaissance Technologies. I had long conversations with Simons — enduring his chain-smoking for hours at a time. I talked to dozens of his executives, researchers and friends. The response to the book was positive, but the question kept coming: What was really behind perhaps the most successful investment firm of all time?

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