Microsoft is buying the parent company of Ciao.com, an online price comparison and product reviews site, as it seeks to improve its European search offering to compete with Google.

Greenfield Online, Ciao's parent company, yesterday agreed to a $486m offer from Microsoft. The company, which is listed on Nasdaq and gains most of its revenues from its internet surveying business, had previously agreed a takeover bid from Quadrangle Group, a private equity firm focused on media and technology, priced at $15.50 a share.