John Thaler, the founder of tech-based long/short equity hedge fund JAT Capital, was one of the best performing hedge fund managers in the world last year ending a volatile 2011 up 12.7%.
And at one point last year everyone on The Street was talking about how Thaler was up more than 30% YTD.
This year it has been a completely different story.
Dealbook reports that Thaler's JAT is down ~20% so far this year, according to internal documents from the fund.
According to the report, those losses are tied to his long bet on Tempur-Pedic and his shorts on Alibaba.com and Weigh Watchers.
Still, the year is only half way over.
Thaler was a star at Chris Shumway's fund Shumway Capital Partners where he worked as a tech analyst and eventually a portfolio manager before it closed in 2010.
He left Shumway in 2007 to found JAT Capital with $200 million, the report said. JAT currently has $2.3 billion assets under management.
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