Eric Lefkofsky knows the public listing rodeo well and is about to enter it for a fourth time. The serial entrepreneur, whose net worth is estimated at nearly $4 billion, has already taken three businesses he’s founded public. Today he’s the founder of Tempus, a genomic testing and data analysis company preparing to IPO. But he’s best known as the cofounder of daily deals pioneer Groupon, which went public at a valuation of nearly $13 billion in 2011, in one of that year’s most high-profile debuts.  Groupo ...