Notoriously litigious paparazzi agency X17 is getting its ass handed to it in a new lawsuit launched by basketball player Tony Parker, husband of Eva Longoria. Filed yesterday, the San Antonio Spurs point guard is seeking $20 million in damages for defamation and invasion of privacy after X17 claimed he cheated, in a series of published text messages, on his now-wife with French model Alexandra Paressant.

“X17 had to know that the story was false, or at the very least, it had to have entertained serious doubts about the credibility of its supposed source,” says Parker in the suit. “No one from X17 attempted to contact Mr. Henry, who … would have told them in no uncertain terms that this woman was not at the wedding.” Nor would they retract their statements when Parker’s camp argued the allegations were false.

This is only the latest in harsh attention X17 – who we’ve had our share of dealings with – has attracted for itself by trying to build a web presence. A number of celebrity weeklies we’ve spoke with have grown wary of the agency because it publishes, on its own website, so many of the photos it then tries to take to market and sell; to tabloid editors, it’s making less and less sense to purchase images (even for a few thousand dollars for the inside pages) that X17 is using to double-dip for revenue.

And X17 is making even fewer friends inside the paparazzi scene. Its egregiously aggressive tactics in stalking celebrities and chasing down photos have resulted in a number of horror stories told to us personally, from driving other photographers off the road to sending threatening emails and phone calls to other paparazzi to stay away from their turf, or else.

Their M.O. is particularly aggressive when it comes to train wreck Britney Spears, who’s long been reported inside the industry to be receiving hundreds of thousands of dollars each month from X17 to constantly alert them to where she’s going to be ahead of other agencies. It’s also turned X17 VP Brandy Navarre into a self-professed Britney expert, and drawn ire (and rolled eyes) from fellow agency chiefs.

On her end, Britney is said to be responsible for changing her look on a near daily basis to ensure each set of photos is marketable. (Celebs who know better will wear the same outfit multiple days in a row, making successive shots essentially worthless, and the business of stalking them not very profitable.)

It came as no surprise when X17 and Britney teamed up to sell a signed CD for “charity”; calls to UNICEF, where the $7,000 winning bid was supposedly destined for, can’t confirm they ever received the donation.