UPDATE 1-Samwer brothers buy stake in Facebook

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LONDON, Jan 15 (Reuters) - German Internet entrepreneurs the Samwer brothers have taken a stake in social networking site Facebook, Alexander Samwer told Reuters on Tuesday.

Samwer, who declined to reveal the size of the stake, said the brothers would now become Facebook’s strategic partners in Europe.

“We are going to support the expansion of Facebook in Europe ... We know the online space in Europe extremely well,” Samwer said in a telephone interview.

Samwer would not disclose the size of the investment, except that it was a “significant” amount, and less than the $240 million Microsoft paid for a 1.6 percent stake in Facebook in October, which valued the site at $15 billion.

"We think Facebook is, after Google GOOG.O, the most innovative company to have emerged in the last few years. We think it will be the phenomenon for the Internet that Windows was for the desktop," Samwer said.

Alexander, alongside brothers Oliver and Marc, made their name in 1999 when they sold German Internet auction site to eBay for $50 million in shares.

After a brief spell working for eBay, they then set up ringtone firm Jamba, which they sold to the U.S. company Verisign for $273 million in shares and cash in 2004. (Editing by Will Waterman)