Legal Definitions - Blonder–Tongue doctrine

The Blonder-Tongue Doctrine is a legal principle that applies to patent law. It states that a patent holder is prevented from relitigating an issue that has already been decided in a previous court case. This is known as collateral estoppel.

For example, if a patent holder sues a company for infringing on their patent and loses the case, they cannot sue another company for the same infringementbased on the same argument. The issue of infringement has already been decided in the previous case, and the patent holder is barred from relitigating it.

The Blonder-Tongue Doctrine helps to prevent patent holders from using the legal system to harass or intimidate companies that they believe are infringing on their patents. It also helps to promote consistency and finality in court decisions.