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Merely Stating That Testing of Potentially Infringing Products Is Expensive Is Not Good Cause To Amend Infringement Contentions Under Northern District of California’s Patent Rules

Recently, a Court in the Central District of California, applying the Patent Rules from the Northern District of California, held that the plaintiff failed to demonstrate the requisite good cause to amend its infringement contentions to add additional accused products. In particular, Plaintiff Kruse Technology Partnership (“Kruse”) sought to add new engines to its infringement contentions based on its recent testing of the engines. In denying Kruse’s motion for leave to amend its infringement contentions, the Court took issue with Kruse for failing to explain why it had not tested the accused engines before it filed its infringement contentions. In doing so, the Court held that “[m]erely stating the tests are expensive is insufficient,” particularly where Kruse was able to later acquire and test the engines at issue. The Court also noted that Kruse never did disclose the cost of the testing. The Court further rejected Kruse’s argument that any disruptions caused by its amended contentions were contemplated by the Patent Rules. The Court found that, while the Patent Rules allow for disruptions caused by timely amending infringement contentions, the disruptions resulting from Kruse’s proposed amendments were not contemplated because Kruse was not diligent in discovering the engines it now seeks to add, and thus its amendments were not justified. The Court found that Kruse’s failure to move to compel discovery on these engines was further evidence of Kruse’s lack of diligence.

Finally, the Court rejected Kruse’s argument that the defendants were put on notice of the engines by listing in its contentions the additional engines and engine families about which it intended to take discovery. Based on Kruse’s lack of diligence coupled with the fact that allowing the amendments would prejudice the defendants in terms of imposing additional discovery obligations and forcing them to develop responsive non-infringement and invalidity contentions in the month and a half that remains before opening claim construction briefs are due, the Court denied Kruse’s motion for leave to include additional engines.

On a related issue, the Court determined that objections to the sufficiency of the infringement contentions were not properly reviewable in connection with Kruse’s motion for leave. Instead, the sufficiency should be litigated on the merits of the claims.

Kruse Technology Partnership v. Daimler AG, et al., Case No. 10-1066 JVS (RNBx) (C.D. Cal. June 17, 2011)
The authors of are patent litigation lawyers at Jeffer Mangels Butler & Mitchell LLP. We represent inventors, patent owners and technology companies in patent licensing and litigation. Whether pursuing patent violations or defending infringement claims, we are aggressive and effective advocates for our clients. For more information contact Greg Cordrey at 949.623.7236 or