The recent Supreme Court ruling in Petrella v. MGM sent shockwaves through the copyright world—at least for those of us in the Ninth Circuit, where laches has long been available as an affirmative defense against purportedly stale claims. Indeed, this decision has already opened the door to a new (or old) crop of copyright infringement cases, including a lawsuit over Led Zeppelin’s “Stairway to Heaven.”

In Petrella, the daughter of “Raging Bull” author Frank Petrella brought an infringement suit against Metro-Goldwyn-Mayer in 2009, some 19 years after she became aware of her potential claims. Rights in Petrella’s 1963 screenplay had been assigned to MGM and other studios, but after the author’s death in 1981, these rights allegedly reverted to his estate. While Paula Petrella learned in 1991 that she could potentially recover her father’s rights to the script, she did not bring suit until 2009, when a Blu-ray disc version of “Raging Bull” was released by MGM.

The lower courts had rejected the Petrella suit based on laches—a doctrine that gives judges discretion to bar a plaintiff from bringing suit due to unreasonable delay. The Supreme Court, however, following the established precedent in the Fourth Circuit, ruled that the only permitted time limit on a copyright action is the three year statute of limitations set forth in the Copyright Act. The Court found that Congress clearly intended to enact the three year limitation period and so despite the potential prejudice to MGM’s business expectations and access to evidence, a judge’s determination of laches cannot override the statute. One obvious implication of this Supreme Court decision is the potential for other rights-holders to bring claims long after discovering the first instance of alleged infringement, provided that the infringement is ongoing.

This doctrine of “separate accrual” is what allows copyright holders to sue for continuing infringement, provided that the last act constituting infringement has occurred within three years. With Petrella removing laches as an affirmative defense, plaintiffs are now potentially able to bring suit many years after initially becoming aware of copyright infringement. Although this may or may not help the plaintiff in Petrella—the case is remanded to the district court—the decision has already apparently motivated potential plaintiffs who have been aware of their potential copyright infringement claims for decades.

The threat of a copyright infringement suit against Led Zeppelin over its legendary 1971 hit “Stairway to Heaven” just became a reality, with the estate of a member of California rock band Spirit having filed its lawsuit less than two weeks after the Petrella decision. The suit, 43 years in the making, has at least one less obstacle to overcome. Led Zeppelin is now releasing an extensive reissue of all nine of its studio albums in chronological order, which provides the alleged “continuing infringement” on which the plaintiff now can to hang its hat. If this latest suit is any indication, we may soon witness a resurgence of dormant copyright infringement claims, long thought unwinnable due to laches.