Less than a month after Facebook's (Nasdaq: FB) controversial and in many ways disappointing, IPO, the social-networking kingpin is now seeing its first C-suite exec bail.

Last week, All Things D reported that CTO Bret Taylor is leaving the company this summer to work on a startup with a friend, Kevin Gibbs. Both Taylor and Gibbs used to work for Google (Nasdaq: GOOG), with Taylor helping to build Google Maps in the early days before leaving Big G soon after it went public in 2004 to create social-networking startup FriendFeed. Facebook acquired FriendFeed in 2009 for an estimated $50 million, which is how Taylor ended up at Facebook.

Taylor was named CTO a few years ago and has been a high-profile exec ever since, helping to lead its platform and mobile initiatives. He was at Apple's (Nasdaq: AAPL) Worldwide Developers Conference last week, when the iPhone maker announced that it's integrating Facebook directly into the next major version of its mobile operating system, iOS 6.

Those are two pretty major strategic areas for the company, as investors are banking on its ability to build and further monetize its payment platform as the next leg of growth, while mobile continues to be a rather ominous soft spot as users continue to migrate to mobile usage en masse and Facebook still tries to figure out how to bring in mobile ad dollars.

Two other Facebook execs are taking over these areas, Mike Vernal and Cory Ondrejka. Taylor said that he "had always been upfront with Mark [Zuckerberg]" about eventually wanting to do another startup and that now was a good time to make the transition. He figured that recent unveilings, such as the Apple partnership, Instagram acquisition and subsequent Facebook Camera release, and launch of its own App Center, signaled about as good a time as any for him to take off.

I'd wager he's enjoyed a sizable payout from the IPO, although he isn't listed in the prospectus as a principal selling stockholder and SEC Form 4s aren't available for him. With Facebook's 91-day lockup period soon to expire in August, some other early Facebook employees are reportedly already waiting with itchy trigger fingers to cash in and move on.

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