A federal judge in San Jose handed a victory to fair-use advocates today, refusing to dismiss a lawsuit that a Pennsylvania woman filed after Universal Music Publishing forced YouTube to remove a video of her children cavorting to an old Prince hit. But it may prove Pyrrhic, as the judge expressed doubt that the woman would ultimately be able to prove her case.

The legal skirmish centers on a 29-second video that Stephanie Lenz posted to YouTube last year that features her then-13-month-old son racing around the kitchen. The video includes a decidedly low-fi recording of Prince's "Let's Go Crazy." At Universal's request, YouTube removed the video and kept it off for more than a month, prompting Lenz to sue. Lawyers from the Electronic Frontier Foundation, which represents Lenz, argued that Universal violated the notice and takedown provision of the Digital Millennium Copyright Act, which says copyright holders can demand the removal of their works from the Web if they have "a good faith belief that use of the material in the manner complained of is not authorized by the copyright owner, its agent, or the law." Because the video was a fair use of Prince's work, the EFF contended, Universal violated the DMCA.

Universal countered by arguing that no copyright holder should have to consider fair use before sending out takedown notices. Fair use is a defense available to those who infringe, not a right, the publisher claimed. Judge Jeremy Fogel disagreed. Here's his reasoning: