Microsoft supposed it has exposed a novel kind of click fraud, filing two court cases against people it says are using the scam.

One of the case, filed in the U.S. District Court for the Western District of Washington, blame the Web site RedOrbit.com and the site's president, of using click laundering, a term Microsoft came up with to explain a novel way of boosting the number of clicks on advertisements on a Web site.

"What was at one point thought to be highly or almost impossible to do, we have uncovered it is technically possible to do," said Richard Boscovich, an attorney in Microsoft's digital crimes unit.

Microsoft accuses RedOrbit, which was once an approved site on its AdCenter network, of using botnets and so-called parked sites to dramatically drive up the number of clicks on ads on the RedOrbit site.

But rather than simply use the botnets and sites to direct clicks to ads on RedOrbit.com as fraudsters commonly do, RedOrbit directed the traffic to its own servers where it scraped out the traffic referring information and replaced it with code that made it look like the traffic came directly to the approved RedOrbit site, Microsoft says.

"That was a unique feature. This is the first time we've seen this occur," Boscovich said.