the trader who made $290 million shorting — his own company

David Einhorn's short of Lehman Brothers wasn't just profitable — it was personal. After working as a Lehman partner earlier in his career, Einhorn launched Greenlight Capital in 1996 and became one of Wall Street's most feared short sellers. By early 2008, he'd identified something rotten in Lehman's balance sheet: the bank was hiding billions in bad real estate loans through accounting tricks and repo agreements that made their leverage look safer than it actually was.

In April 2008, Einhorn gave a now-legendary presentation at the Ira Sohn Conference where he systematically dismantled Lehman's financials, arguing they were obscuring massive losses. He called out their 'Repo 105' maneuver — temporarily moving assets off the books before quarterly reports — and questioned why CEO Dick Fuld kept insisting everything was fine while the evidence screamed otherwise. The financial press started paying attention. Lehman's stock began its death spiral.

Greenlight's bet paid off spectacularly. As Lehman cratered through the summer, Einhorn's fund made an estimated $290 million on the short — one of the most profitable single trades of the financial crisis. The irony wasn't lost on anyone: a former insider had called the bluff, and Wall Street's fourth-largest investment bank evaporated in September 2008, taking the global economy with it.

Einhorn later testified before Congress about Lehman's collapse, arguing that regulators had ignored his warnings for months. The short made him a hero to some, a vulture to others — but nobody could argue with the tendies. Diamond hands on that thesis, even when half of Wall Street called him crazy.