The practice, known as "click fraud," began in the early days of the Internet's mainstream popularity with programs that automatically surfed Web sites to increase traffic figures. This led companies to develop policing technologies touted as antidotes to the problem. But some marketing executives estimate that up to 20 percent of fees in certain advertising categories continue to be based on nonexistent consumers in today's search industry.
In one recent example of the problem, law enforcement officials say a California man created a software program that he claimed could let spammers bilk Google out of millions of dollars in fraudulent clicks. Authorities said he was arrested while trying to blackmail Google for $150,000 (£80,164) to hand over the program. He was indicted by a California jury in June.
Matt Parrella, chief of the San Jose branch of the US Attorney's Office in Northern California, said that case was "not unique." The problem "is certainly not shrinking, and we're ready to prosecute people," said Parrella, whose office handled the Google case.
Click fraud is perpetrated in both automated and human ways. The most common method is the use of online robots, or "bots," programmed to click on advertisers' links that are displayed on Web sites or listed in search queries. A growing alternative employs low-cost workers who are hired in China, India and other countries to click on text links and other ads. A third form of fraud takes place when employees of companies click on rivals' ads to deplete their marketing budgets and skew search results.
Although the extent of click fraud is impossible to measure with any certainty, its persistence has exposed a fundamental weakness in the promising business of Internet search marketing. Google's pending initial public offering has been widely anticipated as a barometer of online advertising and the post-apocalyptic dot-com climate in general.
"It's hard to tell how big the problem is, but people are looking at it closer and closer as the cost of search advertising goes up," said John Squire, vice president of business development of Coremetrics, a Web analytics firm. "Click fraud is a fin sticking out of the water: You're not sure if it's a great white shark or a dolphin."
