Venture capital player Kleiner Perkins Caufield & Byers has bought US$38m worth of stock from Facebook shareholders in a transaction that values the social networking giant at US$52bn.
This is slightly higher than the investment by DST Global and Goldman Sachs in recent months, which valued Facebook at US$50bn.
Veteran firm Kleiner Perkins Caufield & Byers invested early on in internet success stories Google, Amazon.com and Netscape.
It missed out on investing in Facebook in 2005, investing instead in social networking site Friendster.
Kleiner Perkins Caufield & Byers recently invested in deal-of-the-day website Groupon and microblogging site Twitter, and invested in social network game developer Zynga in 2008.