In all of the approaches, fraudsters can use a combination of automated software robots, called clickbots, to initiate clicks and people who physically hit clicks. While Google and Overture do proactively inform advertisers of the click fraud they detect, the majority of the burden for finding and proving click fraud has fallen to advertisers, panelists said."Search engines are profiting and have not published rules that speak to an investigation or give those harmed the information to get to the bottom of problem," said Ben Edelman, an Internet privacy research and Harvard University student.Advertisers can analyze click patterns, visitor logs and other information, but Edelman said the search engines themselves should be able to access more detailed information that could help advertisers track down click fraud and even prove it in court. So far, click fraud has yet to be tested in court, but panelists and attendees largely agreed that they expect cases to emerge both against alleged fraudsters and possibly against the search engines. "While we know this is happening, there are no reported cases on this yet," said Peter Raymond, a partner at law firm Reed Smith LLP, in New York. "Obviously theres a real problem in gathering this proof to bring this kind of case." Check out eWEEK.coms for the latest news, views and analysis on enterprise search technology.