A recent order the District of New Jersey highlights the importance of diligence in establishing good cause to amend a party’s contentions, and that a claim construction ruling is a not a free pass to amend infringement contentions.  Takeda Pharmaceutical Co. Ltd., et al. v. Sun Pharma Global FZE et al., Case No. 14-cv-4616 (D.N.J.) at Dkt No. 121.*  The Magistrate’s Order was Affirmed by the District Court on appeal.  Id. at Dkt No. 113.

In January, Takeda filed a motion requesting leave to amend its infringement contentions pursuant to L. Pat. R. 3.7.  In an effort to show this request was supported by good cause, Takeda argued that the District Court adopted a claim construction that “was different from that proposed by both parties,” and that the time period for determining diligence in support of a finding of good cause should be measured from the date of the claim construction order.  Takeda suggested that while the District Court had adopted one part of Sun’s proposed construction regarding a claim phrase, it had also rejected two portions of the defendants’ construction, and therefore the District Court’s construction was different than that proposed by either party.  The Court responded that the constructions may be technically different, “but hardly fundamentally so.”  The Court also seized on Takeda’s admission that its request to amend was based on noninfringement positions provided by Sun approximately eight months before the District Court issued its claim construction order.  Therefore, the Court held that Takeda was on notice of Sun’s proposed construction, was “fully equipped to act sooner,” and the timing of Takeda’s motion for leave was the result of its lack of diligence, not an adverse claim construction order.

The Court’s order, coupled with the claim construction ruling, effectively eliminated any infringement claims by Takeda against Sun.  The Court’s order also provides a strong reminder about the importance for a party to vigilantly supplement its infringement and invalidity contentions in response to its adversary’s contentions and other events, such as proposed claim constructions, that may trigger a need to amend contentions related to infringement and invalidity.  Failure to do so may be fatal to any attempts to address those contentions at a later date.

*Sun Pharma Global FZE and Sun Pharmaceutical Industries, Ltd. are represented in this matter by Carlson Caspers.