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Agency by Estoppel

A situation in which a reasonable person may assume agency agreement exists when it does not. For example, if a person or company allows another person or company to use proprietary letterhead to send out correspondence, agency by estoppel may exist. Because the agency is assumed, the (presumed) principal may be legally bound by the agent's actions.


A doctrine that stops one from denying facts or taking a course of action because it would be unfair under the circumstances.It may be because someone else relied on former statements regarding the facts or because someone else relied upon a situation allowed to exist by a party, so that the party cannot now be allowed to change that situation.The concept commonly arises in three situations:

1. Before the sale of an income-producing property, the tenants sign estoppel certificates acknowledging they have no claims against the landlord, no defenses to any of the terms or conditions of their lease, and no outside or “side” agreements varying the terms of the lease. After the sale, the tenant cannot claim otherwise, even if all parties agree that there has been a wrong done to the tenant by the prior landlord and the tenant would otherwise be able to cancel the lease if it were not for the estoppel certificate.

2. A subdivision with restrictive covenants grows lax in the enforcement of them and per- mits many violations over the years regarding, for example, parking boats and motor homes in driveways. If one buys a home in the subdivision and keeps a motor home in the driveway, the principle of estoppel will prevent the homeowners association from suddenly deciding to enforce that particular covenant.

3. A government employee tells someone one thing, and it later turns out to be wrong. The citizen has already taken action on the incorrect information. In most circumstances, courts will not allow estoppel against a government or government agency.

References in periodicals archive ?
116(C)(7), concluding that collateral estoppel precluded Dinehart's claim.
The estoppel attaches upon issuance of a final written decision from the PTAB; i.
14) It, therefore, superseded common law liability based on estoppel and unjust enrichment.
28 Although numerous attempts have been made to identify the various components of equitable estoppel, for present purposes, the matters which a plaintiff must establish to found an equitable estoppel may conveniently be summarised, in the present context, as follows:
The board replied, explaining the error; however, in December, Spiewacki appealed that decision under an equitable estoppel argument-i.
Another way in which courts have improperly expanded the federal policy favoring arbitration to give non-signatories broader rights to enforce arbitration clauses than other contract provisions is through the doctrine of equitable estoppel.
This article argues that courts should develop an exception to the doctrine of collateral estoppel in attorney disciplinary proceedings to allow the attorney to have a full and fair opportunity to be heard.
Judicial estoppel is an equitable doctrine designed to protect the integrity of judicial proceedings by preventing litigants from asserting contradictory positions for tactical gain.
These two forms of estoppel, which have differing requirements, themselves give rise to causes of action.
Thus, the requirement of identicality was not met, and collateral estoppel does not apply:'
And there's no estoppel, so if the re-examination upholds the patent, a challenger can still present the same validity attack in another proceeding.