On September 1, 2009, an investor group that included Andreessen Horowitz acquired a majority stake in Skype for $2.75 billion, which was considered risky. The deal paid off in May 2011 when Microsoft bought Skype for $8.5 billion. Additionally, Andreessen and Horowitz made personal Investments in headset maker Jawbone in 2006. The firm announced a $49 million investment in Jawbone in March 2011. In February 2011, Andreessen Horowitz’s $80 million investment in Twitter made it the first venture firm to hold stock in all four of the highest-valued, privately held social media companies (at that time): Facebook, Groupon, Twitter, and Zynga.