Uber IPO: Here's what 12 of Uber's earliest employees are doing now

10 years after Uber began as a tiny startup called UberCar, it's going public in one of the biggest IPOs ever.Some of Uber's earliest employees, such as former CEO Travis Kalanick and cofounder Oscar Salazar, are no longer at the company.Others, such as Rachel Holt and Austin Geidt, have stayed on and steadily moved up in the company.Here's a look at 12 of Uber's first employees and what they're doing now.Visit Business Insider's homepage for more stories.In 2009, a tiny startup called UberCab was founded; today, it's just called Uber, and it's one of Silicon Valley's most successful companies. Uber operates in more than 700 cities worldwide.Now, Uber is going public in one of the biggest IPOs of all time with an initial market cap of $75.5 billion. Trading opened at $42 per share. Some of Uber's first investors could make up to $1.3 billion in total from the IPO, according to Bloomberg.Read more: Uber is sliding after its IPO, and Main Street traders who struggled to invest dodged a bulletMany of Uber's earliest employees still work at Uber, including former intern Austin Geidt, who's now the Head of Strategy for the company's Advanced Technologies Group and rang the opening bell at the New York Stock Exchange on the day of Uber's IPO.Others have left to pursue other startups and related ventures. At least three of the company's early employees — former CEO Travis Kalanick, Ryan Graves, and Garrett Camp — are now billionaires.Here's what 12 of Uber's earliest employees are doing now.