The group asks a judge to dismiss a lawsuit filed the day before Adam Yauch died because casual observers won't be able to identify the source of samples.

The Beastie Boys have finally responded to a lawsuit that alleges the group illegally sampled material on the 1986 album License to Ill and the 1989 album Paul's Boutique.

TufAmerica, a record label, filed its complaint the day before Adam Yauch died, which led to delay in a response.

On Monday, the group's lawyers asked a judge to find that the plaintiffs can't establish substantial similarity between original recordings and the Beasties' work, and even if TufAmerica can support copyright infringement claims, to limit the liability thanks to the fact that License to Ill and Paul's Boutique came out more than two decades ago.

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The crux of the dispute is that before the Beastie Boys used copyrighted samples on their hit albums, they allegedly needed but failed to get authorization.

For years, unauthorized sampling in hip-hop was ignored, but that's no longer the case. One explanation might be that record labels are looking for new revenue sources. Another explanation -- with more provocative implications -- is that advancing musicology technologies are giving potential plaintiffs greater power to trace sampling sources.

Whatever the reason, the attorneys for the Beastie Boys hint that a fuller explanation is in order.

"What precipitated Plaintiff to bring this action two decades after the release of the songs in question, and the day before the passing of defendant Adam Yauch, is not explained. Plaintiff is attempting to sidestep the Copyright Act's three-year statute of limitations and the defenses of laches and estoppel in light of its decades-long delay in taking any action."

The lawsuit charges the Beastie Boys with incorporating the recordings "Say What" and "Drop the Bomb," performed by the group Trouble Funk, into songs such as "Shadrack," "Car Thief," "Hold It Now Hit It" and "The New Style."

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TufAmerica says the samples were "effectively concealed" to "the casual listener" and that they were discovered "[o]nly after conducting a careful audio analysis."

If that's true, say the Beastie Boys, it's proof that their own work is different from the material owned by TufAmerica. "Because Plaintiff admits that the casual observer cannot identify Plaintiff's musical compositions and sound recordings... there can be no substantial similarity."

For an inkling of how TufAmerica might respond to such an argument, we'll turn to another illegal sampling war currently being waged.

Madonna is currently being sued for allegedly sampling a 1976 composition owned by VMG Salsoul on the 1990 hit song "Vogue." The plaintiff in that case also alleges that it was only through new technology that the "deliberately hidden" sampling had been detected. In response to those allegations, Madonna's producer is attempting to defeat the lawsuit on grounds that the alleged copying was de minimis, as an ordinary observer cannot detect it.

Late last month, VMG Salsoul had a retort to that defense, saying in court papers that Madonna and her producer integrated the sampled music "in such a way that the fact that it was sampled was disguised, not that the sounds and music of Plaintiff's sound recording itself were somehow hidden."

The ability to detect similarity is not only important to the essential question of whether copying has taken place, but it also factors into potential damages that can be collected. As the Beastie Boys note, the Copyright Act has a three-year statute of limitations, but the clock usually starts when the infringement is or should have been discovered.

In instances where plaintiffs delay in bringing a court action, the law usually only allows them to collect damages for the past three years -- meaning here, from 2009-2012 instead of on the years when the albums were top-sellers. In some instances, when a judge finds that a plaintiff has made an unreasonable delay in a way that prejudices the opposing party, no damages can be collected.

The Beastie Boys say such is the case here.

According to the motion to dismiss:

"Any claim for copyright infringement would accrue when Plaintiff knew or had reason to know of the injury, and Plaintiff's claims would be time-barred because the songs "Hold It Now Hit It," "The New Style," "Shadrach" and "Car Thief" are hip hop classics and have been played for nearly a quarter of a century in concerts, on the radio, by the public and in public venues."

E-mail: eriq.gardner@thr.com; Twitter: @eriqgardner