It's all fun and games until somebody files a civil complaint.

The U.S. Chamber of Commerce filed suit yesterday in federal district court against The Yes Men, the group of pranksters who perpetrated the fake Chamber press release last week claiming the business group had reversed its climate-change stance and announced support for Democratic cap-and-trade policies in a speech by its president at the National Press Club.

The Chamber says it filed the suit after its lawyers asked The Yes Men to dismantle a fake Chamber website it set up for the prank, which uses the Chamber's logo, and the pranksters refused.

The Yes Men, meanwhile, are in the midst of promoting a new movie. The Chamber pointed to the group's own commercialism, seeking to puncture the aura of an impish jab at Big Business.

"The defendants are not merry pranksters tweaking the establishment.  Instead, they deliberately broke the law in order to further commercial interest in their books, movies, and other merchandise," said Steven Law, the Chamber's chief legal officer.

The Chamber also recognizes that the suit might actually help The Yes Men in those commercial aims.

"Ironically and unfortunately, this lawsuit might even help in that regard, but these acts are nothing less than commercial identity theft masquerading as social activism and must be stopped," Law said.

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