Laches is an equitable defense that punishes plaintiffs for waiting too long to enforce their rights. Or, put another way, it protects defendants who may have a reasonable expectation not to be sued simply based on the length of time the plaintiff knew about—but did not take action against—an alleged infringement. To invoke it, a defendant must generally show two things: unreasonable delay by the trademark owner in bringing suit after learning of the alleged infringement and that the defendant suffered actual prejudice because of the delay (like by investing in the brand in the interim).
The defense to the laches defense, or at least one of them, is the idea of progressive encroachment. Sometimes infringement starts very small. And sometimes those small infringements burn themselves out (businesses fail, product lines are abandoned, etc.) without the need for aggressive action like a lawsuit. Shouldn't trademark owners have the freedom to make the practical choice to watch-and-see rather than run to court over every start-up that may be infringing? They do.
Progressive encroachment is the idea that a trademark owner's delay in suing should be measured not from the moment the owner first learned of the defendant's use, but from the point at which the infringing activity became serious enough to justify the burden and expense of litigation. A court will look at a few factors, including how minor the initial infringing activity was, whether it later expanded materially (such that the nature of the harm materially changed), and whether the defendant can identify prejudice specifically from the period after the infringement escalated.
Progressive encroachment is seeing more applicability given the popularity of e-commerce. A defendant that was selling a few items here and there out of a basement can open up a drop-ship business and overnight start selling three or four times as much product, with a national or international scope.
That was the case in the recent decision in favor of Birkenstock against alleged infringer White Mountain. Birkenstock had been aware of White Mountain (allegedly) since the 1990s, but didn't file a lawsuit until 2024. White Mountain tried for summary judgment on the basis of laches. A Massachusetts federal judge found too many factual disputes to determine whether Birkenstock waited too long to sue, including around how insignificant sales were prior to 2018 (the alleged date when sales exploded 700% due to initiation of a drop-ship business), details of back-and-forth letters that began in 2021, and whether those tolled the laches period. Unclear whether the laches defense or the defense to the laches defense will carry the day. It will have to be tried.
The takeaway for trademark owners is that vigilance does not always require immediate litigation, and that a successful progressive encroachment theory will rest on strong documented evidence around defendant's growth over time, as well as (possibly) any prior cease and desist activity. For would-be defendants, the warning is that a demand that goes quiet is not necessarily a win. The Catch-22 for a defendant in this scenario is that the kind of success they're dreaming of also means that an early nasty-gram might come back with a vengeance.
