Today, in SCA v. First Quality, the Federal Circuit sitting en banc ruled that the equitable doctrine of laches remains a valid defense in patent infringement actions notwithstanding the Supreme Court’s recent decision in Petrella v. MGM, 134 S. Ct. 1962 (2014), that precludes laches as a defense for copyrights.  This decision was not too surprising given the wording and history of the patent statute and laches defense as compared to copyright law.  But the Federal Circuit did make some changes as to the applicability of laches for on-going infringement after the patent suit is filed:

Specifically, as to injunctions, considerations of laches fit naturally within the eBay framework.  In contrast, Menendez v. Holt, 128 U.S. 514 (1888), and Petrella counsel that laches will only foreclose an ongoing royalty in extraordinary circumstances.

That is the key take-away from this decision.  You may find it to be a lengthy, but interesting, read on the history of the laches defense in patent cases.  We will see how the twist on applying laches post-suit for on-going infringement will develop.

With respect to an on-going royalty post-suit in the absence of an injunction, the Federal Circuit’s decision was premised on maintaining the distinction between laches, which focuses on the patent owner’s delay in filing suit, and equitable estoppel, which focuses on misleading acts by the patent owner that led the accused infringer to believe it could proceed with what later is alleged to infringe:

With respect to ongoing royalties, while the principles of equity apply, equity normally dictates that courts award ongoing royalties, despite laches.  Menendez, an influential case contrasting laches and equitable estoppel in the trademark context, guides us here.  According to Menendez, delay in exercising a patent right, without more, does not mean that the patentee has abandoned its right to its invention.  Rather, the patentee has abandoned its right to collect damages during the delay.  Equitable estoppel, on the other hand, is different–the patentee has granted a license to use the invention that extends throughout the life of the patent …

… Menendez and Petrella caution against erasing the distinction between laches and estoppel.  As Petrella stated, “the doctrine of estoppel may bar the copyright owner’s claims completely, eliminating all potential remedies.  The test for estoppel is more exacting than the test for laches, and the two defenses are differently oriented.  The gravamen of estoppel … is misleading and consequent loss.  Delay may be involved, but is not an element of the defense.  For laches, timeliness is the essential element.  For that reason, absent egregious circumstances, when injunctive relief is inappropriate, the patentee remains entitled to an ongoing royalty. [internal citations omitted]

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