Back in 2007, Eric Lefkofsky and Brad Keywell invested in a struggling Internet startup, Groupon.

FORBES: Lightbank: A Talk With Groupon's VC Backer

Last year, the co-founder of Groupon ( NASDAQ:GRPN), Brad Keywell, gave a keynote speech.

FORBES: Groupon's Accounting Mistake, the Media, Quant Funds and Academic Case Studies