Included in the purge at least temporarily were Death Cab for Cutie -- a Warner group that embedded YouTube clips on its own site -- and individuals like Will Chatham, who posted a video of himself playing the "Star Wars" theme on his banjo.
Now, Stanford Law professor Lawrence Lessig, author of the book "Remix" and a leading advocate of copyright reform, appears to have joined the ranks of people whose clips have been deleted from the video-sharing site.
Earlier this week, Lessig alleged on Twitter that Warner Music had issued a takedown notice for one of his presentations that had been posted to YouTube. Lessig tweeted that he intended to contest the takedown.
The clip appears to have been of slides Lessig delivered March 24 at a conference in San Diego, according to a subsequent post on Twitter. In that presentation, Lessig advocated for copyright reform and also included examples of other people's remixes.
Lessig is traveling overseas and was not available to comment.
As of Thursday evening, it wasn't clear why the clip had been taken down. Lessig's post alleged that Warner Music requested the takedown. It appears that either YouTube's "digital fingerprint" tool flagged the clip for deletion based on automated settings input by Warner, or that a third party made the request on Warner's behalf.
Either way, copyright reform advocates say the incident illustrates a larger problem of overly aggressive takedowns of user content. "Larry Lessig is not alone," said Corynne McSherry, an attorney with the digital rights group Electronic Frontier Foundation. "Unfortunately, this is one of many, many, many examples where obvious fair uses get taken down."
YouTube's policy is to remove material upon receipt of complaints, but the site also allows users to contest the notices. If users do so, the site reviews clips manually to determine whether they're legitimate under fair use principles.
YouTube counsel Zahavah Levine says the site takes into account the owners' interest in protecting copyright and consumers' interests in expressing themselves. "We don't trample on fair use rights," she said. "We work hard to balance all the legitimate interests at stake here."