Estoppel is a judicial device in common law legal systems whereby a court may prevent or "estop" a person from making assertions or from going back on...

An Estoppel Certificate (or Estoppel Letter) is a document commonly used in due diligence in real estate and mortgage activities. It is based on estoppel...

Collateral estoppel (CE), known in modern terminology as issue preclusion, is a common law estoppel doctrine that prevents a person from relitigating an...

The doctrine of assignor estoppel is a doctrine of United States patent law barring a patent's seller (assignor) from attacking the patent's validity in...

In the common law, judicial estoppel (also known as estoppel by inconsistent positions) is an estoppel that precludes a party from taking a position in...

Prosecution history estoppel, also known as file-wrapper estoppel, is a term used to indicate that a person who has filed a patent application, and then...

Estoppel in English law is a doctrine that may be used in certain situations to prevent a person from relying upon certain rights, or upon a set of facts...

direct estoppel prevents a party to  litigation from relitigating an issue that was decided against that party. Direct estoppel and collateral estoppel are...

similar to acquiescence include: The common law doctrine of estoppel. A claim of estoppel may arise when one party gives legal notice to a second party...

Proprietary estoppel is a legal claim, especially connected to English land law, which may arise in relation to rights to use the property of the owner...