The U.S. Court of Appeals for the Federal Circuit (CAFC) recently made a significant ruling in a case involving Wisconsin Alumni Research Foundation (WARF) and tech giant Apple, Inc. The CAFC upheld two district court judgments in favor of Apple, finding that WARF had abandoned its doctrine-of-equivalents theory in the first trial (WARF I) and that a subsequent suit (WARF II) claiming infringement of the same patent was barred by the previous decision.
The legal battle between WARF and Apple began in 2014 when WARF accused Apple of infringing a patent (U.S. Patent No. 5,781,752) with its processors. In the first trial, known as WARF I, Apple initially claimed both literal infringement and infringement under the doctrine of equivalents. However, Apple dropped the latter theory after WARF opposed Apple’s motion to exclude evidence related to Apple’s own patent application.
The jury in WARF I found in favor of WARF on literal infringement, but Apple later moved for judgment as a matter of law, arguing that no reasonable jury could find literal infringement based on the interpretation of the term “particular.” The district court ultimately ruled in favor of Apple, leading to a reversal by the CAFC in 2018.
Following the unsuccessful appeal, WARF sought a new trial based on a doctrine of equivalents theory. However, the district court denied the request, noting that WARF had abandoned its doctrine-of-equivalents theory in exchange for Apple’s agreement not to introduce its own patent during the trial. The CAFC affirmed this decision, stating that the record clearly showed WARF’s intentional abandonment of the theory.
In a second suit (WARF II), WARF attempted to argue that Apple’s later processors infringed under the doctrine of equivalents. Apple opposed this, citing issue preclusion and the Kessler doctrine to prevent WARF from pursuing the claim. The CAFC agreed with Apple, citing similarities between the processors in both cases and rejecting WARF’s reliance on a trademark case to support its argument.
The CAFC’s decision clarified that WARF’s understanding of legal precedents was too broad and that the issues in both trials were essentially the same. The court also invoked the Kessler doctrine to prevent what it deemed as “litigation harassment” against Apple by WARF.
Overall, the CAFC’s ruling in favor of Apple in both WARF I and WARF II underscores the importance of strategic legal decisions and the consequences of abandoning legal theories in complex patent infringement cases. The prolonged legal battle between WARF and Apple serves as a reminder of the intricacies of intellectual property law and the need for careful consideration of legal strategies in high-stakes litigation.