The equitable defenses of acquiescence and laches are very similar. “Laches is an equitable time limitation on a party’s right to bring suit resting on the maxim that one who seeks the help of a court of equity must not sleep on his rights.” The Ninth Circuit test for laches is two-fold: First, was the plaintiff’s delay in bringing suit unreasonable? Second, was the defendant prejudiced by the delay? The first aspect of that test, in turn, consists of two sub-parts: an assessment of the length of the delay, followed by an assessment of the reasonableness of the delay.
On the other hand, acquiescence, limits a party’s right to bring suit following an affirmative act, by word or deed, by the party that conveys implied consent to another. Although the Ninth Circuit previously had addressed the acquiescence defense in passing, it never had articulated a definition or established a practical test for district courts to apply.
The Court explained that the test for acquiescence test essentially is a modified version of its laches test. Acquiescence differs from laches principally in that it requires some form of active consent. Thus, the Court announced, the elements of a prima facie case test for acquiescence in the Ninth Circuit are now as follows:
The case, Seller Agency Council, Inc. v. Kennedy Center for Real Estate , U.S. Court of Appeals for the Ninth Circuit, Case No. 08-56791 (2010) is available here.(1) the senior user actively represented that it would not assert a right
or a claim;(2) the delay between the active representation and assertion of the right or claim was not excusable; and
(3) the delay caused the defendant undue prejudice.