What legal principle asserts that a claim will not be enforced if a long delay in asserting it has harmed the other party?

The correct answer, which is laches, is a legal doctrine that prevents a party from asserting a claim after an unnecessary delay that has prejudiced the opposing party. This principle is rooted in fairness and aims to encourage the timely pursuit of legal remedies. If a claimant waits too long to bring a claim, and this delay negatively impacts the other party—potentially affecting their ability to gather evidence or causing their circumstances to change—then the claim may be barred due to laches.

This doctrine is particularly relevant in cases involving property rights, contracts, and equity, emphasizing the importance of diligent action and the need to protect parties from the burden of stale claims. By establishing a time frame for bringing actions, laches seeks to uphold justice and prevent the courts from being burdened with old disputes that have been allowed to linger, causing potential harm to the defendant.

In contrast, other options like reversion relate to the return of property rights under specific conditions, patent ambiguity pertains to unclear terms in legal documents that can be resolved by courts, and salient refers to something that is prominent or stands out, which does not connect to the concept of delaying the enforcement of a claim.