A copyright skirmish is mounting between the Beastie Boys and GoldieBlox, and opinions are divided over which side should blink first.

It all started last week when the privately held GoldieBlox Inc., which makes toys aimed at encouraging young girls to become engineers, posted a video to YouTube advertising its products. The video features three girls creating an imaginative Rube Goldberg-style machine out of their pink teapots, dolls and other toys, and it's set to a parody of the Beastie Boys’ 1987 song “Girls,” in which the band sings cheekily about finding girls “to do the dishes” and “clean up my room,” etc. In the parody version, GoldieBlox reimagines the lyrics as girls “to build the spaceships” and “code the new app,” etc. The final few seconds of the video features a shot of GoldieBlox products, as well as its logo and tagline, “Toys for future engineers.”

The video went viral, with more than 8.2 million views and counting. A few days later, GoldieBlox said the Beastie Boys had threatened to sue the toymaker for copyright infringement. But rather than wait for that to happen, the company filed a legal complaint seeking a declaratory court relief that would rule the parody fair use. In the complaint, posted here by the Hollywood Reporter, GoldieBlox calls the original song “highly sexist” and says the parody “takes direct aim at the song both visually and with a revised set of lyrics celebrating the many capabilities of girls.”

On Monday, in an open letter obtained by the New York Times, the Beastie Boys responded by saying they approve of the video’s message and that they “strongly support empowering young girls, breaking down gender stereotypes and igniting a passion for technology and engineering.” However, they added that they made a “conscious decision” long ago not to permit the use of their music in product ads. “As creative as it is, make no mistake, your video is an advertisement that is designed to sell a product,” the band said.

To complicate matters, founding Beastie Boy Adam Yauch, who died of throat cancer in August 2012, said in his will that “in no event may my image or name or any music or any artistic property created by me be used for advertising purposes.”

The dispute has attracted no shortage of opinions on both sides. Should the Beasties suck it up and take it on the chin or should they take their copyright fight to the courts? The fair use doctrine of U.S. copyright law, which permits the limited use of copyrighted material without permission, is notoriously murky, fraught with gray areas that are often settled on a case-by-case basis. Many fair use cases begin and end with a cease-and-desist letter, with parodists backing off at the threat of possible litigation.

Julie Ahrens, director of copyright and fair use for Stanford University’s Center for Internet and Society, thinks GoldieBlox did the right thing by sticking to its guns. “I think this is a clear parody,” she said in a phone interview. “And I was shocked that the Beastie Boys of all people would be fighting this kind of fight. They’re not copyright maximalists. They’re historical users of copyrighted material that they don’t own and didn’t ask permission for.”

Fair use cases are typically settled using four factors, reposted here by the Electronic Frontier Foundation, which also came out in support of GoldieBlox. The first factor does take into account whether or not the copyrighted material is being used for commercial purposes, but it’s not the defining factor. Ahrens said it’s a misconception that a parody can’t be protected under fair use if it’s used in an advertisement.

“It can be both,” Ahrens said. “Using it as an advertisement may be a small factor, but in this case the product itself and the message they’re using through the product also goes to criticize this whole sexist or misogynist message about what girls should be doing. The product and the company have a social message, and part of that is that girls can do more than wash dishes and do laundry.”

Based in Oakland, Calif., GoldieBlox rose to prominence last year after a Kickstarter campaign to fund a construction set raised more than $285,000 in just a few days. The company declined to comment on the parody skirmish beyond what was said in the legal complaint.

Aside from the letter in the New York Times, Beastie Boys have not commented on the issue. They haven’t filed suit and, in fact, stressed in their letter that it was GoldieBlox that sued them. Given the popularity of the video, and the degree to which its message is resonating, Ahrens said she’d be surprised if the Beastie Boys escalated the quarrel with a copyright lawsuit of their own.

“Call me an optimist, but I can’t imagine this goes very far,” Ahrens said. “It would shock me if they would really care enough to fight this specific use and take the side that this message shouldn’t be out there.”

Watch the GoldieBlox video below.

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