Sam Lessin, a key employee at Facebook and former classmate of CEO Mark Zuckerberg, announced Thursday he is leaving the social-networking giant at the end of the month.
Lessin joined Facebook in 2010 as a product manager after the social network acquired file-sharing service Drop.io. Lessin, who worked on key features such as Timeline and served other product development roles at the company, said in a Facebook post that he was leaving the company with "mixed emotions."
"I am extremely proud and thankful to have had the opportunity to play a small role in a chapter or two of the grand adventure that is Facebook," he wrote.
"This is the first time I can think of since middle school where I didn't have a very concrete next step to take in life, and I intend to not squander the opportunity," he wrote.
Facebook declined to comment on Lessin's departure.
Lessin, 31, joined Facebook after fellow Harvard alumnus Zuckerberg bought the New York-based startup Lessin founded, which let users privately share files through a drag-and-drop interface. But before that acquisition, Lessin's connection to Facebook was deep.
According to David Kirkpatrick's 2010 book "The Facebook Effect," Lessin was a crucial player in Facebook's early days: "At the end of the [spring 2004] semester, Lessin, whose father was a well-known investor, took Zuckerberg around New York to meet with venture capitalists and executives in the finance and media industries," Kirkpatrick wrote.
In addition to taking some time to do some kite-surfing, skiing, and "general adventuring," Lessin wrote that he plans to lend a hand at The Information, a tech news site founded by his wife, Jessica Lessin.