The "dancing baby" of YouTube fame turned 10 years old last month, and he much prefers classical music to Prince.

Yet Holden Lenz's few moments of bouncing to Prince's 1984 hit "Let's Go Crazy" will likely stay with him forever, and not only because of the 1.8 million views of the Pennsylvania boy's 2007 dance performance.

The 29-second video set into motion more than eight years of litigation in federal court that his mother, Stephanie Lenz, hopes will end in victory for the right to free expression online.

If it ever ends.

Like a lot of battles over free expression, we're not talking about censoring Thomas Paine's "Common Sense." Or anything really close to common sense, when it comes to the music industry's overzealous copyright cops.

The story begins on a winter day in Gallitzin, Pa., nine years ago. Stephanie Lenz wasn't trying to make a point with the video. She just wanted to capture her son's bouncy routine whenever he heard the word "music." She had the Purple One on her mind after hearing him perform in the Super Bowl halftime show, and she turned the music up loud so she could hear it over her children's screams of delight.

The star of the video is 13-month-old Holden, high-stepping behind a walker with a big smile. "What do think of the music?" his mother asks, and the boy instantly starts bobbing up and down at the knees. He gives a chirp of happiness, looks around and the video ends.

She uploaded the video to YouTube so her mother in California could see it. Lenz titled the YouTube video " 'Let's go crazy' #1."

That's probably what caught the attention of a legal assistant at Universal Music, Prince's music publisher at the time. Prince has always jealously guarded his music from those who would play it without handing over ­royalties. So his lawyers and record label people are on the constant prowl for copyright violators.

A law called the Digital Millennium Copyright Act (DMCA) requires venues like YouTube to remove content if it receives a "takedown notice" from a copyright holder. Whoever put up the content gets a notification that they have allegedly violated someone's copyright, and it's up to them to make the case that they didn't, if they want their content to go live again.

Lenz's was among more than 200 highlighted in a takedown notice sent to YouTube by Universal. Lenz thought the June 2007 e-mail about the removal of her video was some kind of scam. Then she checked YouTube, and saw that it was gone.

Lenz, a writer and former reporter, feels passionately about free expression issues. So she found her way to the Electronic Frontier Foundation (EFF), a San Francisco group that advocates for civil liberties online.

EFF was already deeply concerned about abuse of the digital copyright law, which requires anyone ordering the removal of content first to consider whether it constituted "fair use." That's the principle that allows such people as artists, journalists and others to use copyrighted material in their own work, as long as it's truly original and not merely a way to profit off someone else's intellectual property.

EFF must have felt it hit the jackpot with the dancing baby video. Could anyone really argue that Stephanie Lenz was stealing Prince's work with 29 seconds of scratchy, distorted music in her kitchen?

Six weeks after it was taken down, the video returned to YouTube. Lenz didn't stop there. She sued Universal in federal court, arguing that it recklessly ignored "fair use" in its digital search and destroy mission.

"It felt wrong to me," she said. "I knew that I had created content, and someone else was claiming it was their copyright."

For a while, the lawsuit stressed her out. Lenz traveled to California for a deposition by Universal's lawyers. She answered calls from reporters. As Holden grew up, his mother had to explain it all to him so he wouldn't be surprised if his name showed up in the news.

The case dragged on and on and on. In September, the Ninth U.S. Circuit Court of Appeals affirmed that Universal must consider fair use before issuing a takedown order, and that it can be sued for damages if it doesn't. At the time, EFF Legal Director Corynne McSherry called it "a strong message that copyright law does not authorize thoughtless censorship of lawful speech."

A strong message, maybe. Hardly the last word. Universal has filed an appeal asking the court to hear the case en banc and dismiss Lenz's claim. EFF has filed its own request for a hearing. Each side has filed answers to the other's motion, and lawyers for Google, Twitter, Tumblr and WordPress have weighed in with an amicus brief.

The dancing baby, meanwhile, went to the Pittsburgh symphony.

Contact James Eli Shiffer at james.shiffer@startribune.com or 612-673-4116.