In Game of Click and Mouse, Advertisers Come Up Empty

"Google is getting a deal," ClickFacts co-founder Michael Caruso said, referring to the Arkansas settlement. "This is chump change to them."

Google reported $6.1 billion in revenue last year.

Caruso said his year-old firm has seen fraud rates for Google ad campaigns range from 20 to 40 percent. Other studies have estimated that bogus clicking accounts for 10 to 30 percent of all clicks on sponsored links.

Click fraud is not new, of course. It has plagued pay-per-click advertising ever since Overture Inc., later bought by Yahoo, pioneered the ad model in the 1990s.

At Yahoo and Google today, merchants compete in online auctions to set pricing for keywords that trigger text links on search-results pages. Radiator.com, for example, pays from 80 cents to $1.20 for each click on sponsored links that appear when someone searches for "radiator," "car radiator" or other phrases.

The two most prevalent types of fraud are competitive sabotage -- rivals clicking to drive up ad costs for competitors -- and affiliate spam -- affiliates clicking on ads appearing on their own sites to boost their share of ad revenue from Google or Yahoo.

Analysts say affiliate spam is more common and really took off after Google launched its AdSense network, which distributes paid links to thousands of non-search sites. They get a share of Google's ad revenue based on clicks, giving unscrupulous publishers an incentive to inflate their clicks.

Yahoo started a similar ad network last summer but limits participation to invited sites to maintain quality and reduce the risk of ad spam, Paez said.

Over the past 18 months, cottage industries have popped up on both sides of this click-and-mouse game.

For $29 or so, anyone can buy fake traffic generator software such as Smart HitBot, Fake Hits Genie and Fakezilla, programs that can send bogus traffic to any Web page or ad.

But click-fraudsters have to watch out because more and more electronic sleuths are trying to catch them. Start-ups with names like Click Tracy, Click Detective and WhosClickingWho analyze traffic and tell advertisers about suspicious activity, such as a surfer in Malaysia repeatedly clicking on ads for a dentist in Baltimore.

Established Web analytic firms are adding fraud-detection capabilities, too. ClickTracks, for example, recently started a service that analyzes 20 variables surrounding each click and compares them with historical data to determine which are legitimate.

Jessie Stricchiola, president of Internet ad consultancy Alchemist Media Inc., said the big stumbling block that search engines face in combating fraud is lack of access to evidence that could prove it -- namely, what customers do after clicking on ads. Bogus visitors almost never buy anything, while a certain percentage of legitimate customers do. Advertisers, however, are reluctant to share sales data with the search engines.

Stricchiola is pushing for standards in Internet ad auditing. She recently teamed with Fair Isaac Corp. to study whether its formulas for detecting credit card fraud might help identify click-fraud.

Cynics fear that the search engines are too afraid of how much revenue they might lose to truly commit to fighting click fraud.

But I can't believe they'd be that stupid. They must know that if they don't find a solution soon, this escalating crisis of confidence could cripple search advertising for years to come.

Leslie Walker welcomes email atwalkerl@washpost.com.