402 U.S. 313, 324–25 (1971)
Respondent University of Illinois Foundation is the owner by assignment of U.S. Patent No. 3,210,767, issued to Dwight E. Isbell on October 5, 1965, for Frequency Independent Unidirectional Antennas, with the application filed on May 3, 1960.1 The antennas covered are designed for transmission and reception of electromagnetic radio frequency signals used in many types of communications, including the broadcasting of radio and television signals.2 The patent has been much litigated since it was granted, primarily because it claims a high quality television antenna for color reception.3 Petitioner Blonder-Tongue Laboratories, Inc. manufactures antennas, and respondent JFD Electronics Corp. is a licensee of the Foundation.4
One of the first infringement suits brought by the Foundation was filed in the Southern District of Iowa against the Winegard Co., an antenna manufacturer.5 After trial to the court and inquiry under Graham v. John Deere Co., Chief Judge Stephenson held the patent invalid as obvious and entered judgment for the alleged infringer.6 The Court of Appeals for the Eighth Circuit unanimously affirmed, and the Supreme Court denied the patentee's petition for certiorari.7 The Foundation has filed six infringement actions based on the Isbell patent.8
In March 1966, well before the ruling in the Winegard case, the Foundation filed suit in the Northern District of Illinois charging a Chicago customer of petitioner Blonder-Tongue Laboratories, Inc. with infringing the Isbell patent and U.S. Patent No. Re. 25,740, reissued March 9, 1965, to P. E. Mayes et al.9 Blonder-Tongue chose to subject itself to the jurisdiction of the court to defend its customer and filed an answer and counterclaim asserting that the patents were invalid, that its antennas did not infringe if valid, and other claims including unfair competition, antitrust, and infringement by JFD models.10
Trial was to the court, and on June 27, 1968, Judge Hoffman held that the Foundation's patents were valid and infringed, dismissed the unfair competition and antitrust charges, and found claim 5 of the B-T patent obvious and invalid.11 Before discussing the Isbell patent, Judge Hoffman noted the prior invalidity holding in Winegard but stated the court was free to decide on the evidence before it and determined both patents valid and enforceable.12
Blonder-Tongue appealed, and the Court of Appeals for the Seventh Circuit affirmed the findings that the Isbell patent was valid and infringed, affirmed dismissal of the unfair competition and antitrust counterclaims, affirmed the invalidity of claim 5 of the B-T patent, but reversed the finding that the Mayes patent was valid.13 Blonder-Tongue sought certiorari, assigning as a primary reason the conflict between the Seventh and Eighth Circuits as to the validity of the Isbell patent, and the Supreme Court granted certiorari, subsequently requesting the parties to discuss whether the holding of Triplett v. Lowell should be adhered to and whether the Winegard determination binds the respondents.14
Whether the holding of Triplett v. Lowell that a determination of patent invalidity is not res judicata against the patentee in subsequent litigation against a different defendant should be adhered to?15
The doctrine of mutuality of estoppel is discarded in patent cases. A prior final judgment of invalidity may be asserted defensively against the patentee provided the patentee enjoyed a full and fair opportunity to litigate validity in the earlier action.16
No. The Foundation litigated the Isbell patent through a full trial in the Southern District of Iowa, where the court applied the Graham v. John Deere Co. obviousness standards, entered judgment of invalidity, secured unanimous affirmance in the Eighth Circuit, and suffered denial of certiorari.17 The Foundation selected the forum, conducted discovery, and presented its evidence, satisfying every element of procedural and substantive fairness.18 Continued adherence to Triplett would permit the same patentee to impose repeated, costly defense burdens on different manufacturers while consuming judicial resources on identical technical questions already resolved after a fair hearing.19
The holding of Triplett v. Lowell should not be adhered to.20
Whether the determination of invalidity in the Winegard litigation binds the respondents in this case?21
Collateral estoppel may be pleaded against a patentee on the basis of an earlier invalidity judgment. However, the patentee must receive an opportunity to demonstrate that the prior proceeding lacked full and fair opportunity before the plea is sustained.22
No. Although the Winegard record shows the Foundation received a full and fair opportunity, the respondents have never been permitted to present evidence or argument on whether that opportunity was in fact adequate, because Triplett previously barred assertion of the estoppel defense.23 The case is therefore remanded to permit amendment of the pleadings, supplementation of the record, and a district-court determination whether estoppel should be imposed in light of the specific facts of the Northern District of Illinois action.24
The determination of invalidity in the Winegard litigation does not automatically bind the respondents without further proceedings to assess the fairness of the prior litigation.25