Click fraud is a big threat - Google CFO

Google\'s Chief Financial Officer George Reyes was referring to the illegal practice known as \'click fraud\' that occurs when individuals click on ad links in order to force advertisers to pay for the clicks. The paid-search model is now the fastest growing form of Internet advertising, according to Interactive Advertising Bureau. But analysts and fraud experts have warned that the rise of click fraud is a growing concern. While there is little hard data available on the extent of click fraud, Jessie Stricchiola of Alchemist Media estimated that as much as 20% of all clicks on paid search ads are shams. Last month Google filed its first civil suit against Auctions Expert that is said defrauded it and advertisers by systematically clicking on ads. Full CNN/Money report