When do the results of claim construction proceedings justify a patent plaintiff in amending its infringement contentions? A court in the Eastern District of Texas allowed the plaintiff to accuse certain software components for the first time following the conclusion of claim construction proceedings. SSL Services, LLC v. Citrix Systems, Inc., No. 2:08-cv-158-JRG (E.D. Texas March 16, 2012).
The court's Local Patent Rule 3-6 allows "a party claiming patent infringement" that "believes in good faith that the Court’s Claim Construction Ruling so requires," to "serve 'Amended Infringement Contentions' without leave of court" within 30 days of the Claim Construction Ruling. The rule further allows amendment of infringement contentions "upon a showing of good cause."
In this case, the court adopted constructions of several claim terms that had been urged by neither party. The plaintiff, SSL, then amended its claim charts to accuse several of Citrix's software components that had not previously been identified in its infringement claim charts, and to add two new theories of infringement under the doctrine of equivalents.
The court allowed SSL to proceed with its amended infringement contentions because "the Court [was] convinced that the constructions adopted by the Court were sufficiently 'different' to justify amendment under the good faith standard of Local Patent Rule 3-6(a)(1)." Further, even if SSL had needed to show cause to amend its infringement contentions, it could have done so. The new claim constructions alone were sufficient to provide SSL cause to amend. In addition, the subject matter at issue was critical to the case. Citrix would not suffer prejudice if the subject matter was included, as evidenced by the fact that Citrix's expert had already submitted a rebuttal report addressing new theories of infringement.