BLONDER–TONGUE DOCTRINE

Blonder–Tongue doctrine.Patents. The rule that a patentee is barred by collateral estoppel from relitigating the validity of a patent that has been held invalid in an earlier proceeding in which the patentee had a full and fair opportunity to litigate the patent’s validity. • The rule was adopted by the U.S. Supreme Court in Blonder–Tongue Laboratories, Inc. v. University of Illinois, 402 U.S. 313, 91 S.Ct. 1434 (1971). — Also termed Blonder–Tongue rule. [Cases: Patents  327(13).][Blacks Law 8th]