In Masimo Corporation v. Philips Electronics North America Corporation, defendant Philips filed a motion for leave to amend its counterclaims pursuant to Federal Rule of Civil Procedure 15 to add a newly acquired patent. C.A. No. 09-80-JJF-MPT, Memo. Order (D. Del. Apr. 20, 2010). Plaintiff argued that this motion to amend was actually an attempt to supplement the pleadings because it was adding a patent that was unrelated to the asserted patents and further was an attempt by defendants to “‘buy up’ new counterclaims and hinder litigation of [plaintiff’s] claims.” Id. at 4 (internal citations omitted).
The Court did treat the motion as a motion to supplement and not a motion to amend, but found that the standard under Rule 15(d) is “‘essentially the same’ as that under Rule 15(a).” Id. at 5 (internal citations omitted). Using that standard, the court found that the newly-added patent is potentially related and inclusion of the patent in the pending litigation “will promote judicial efficiency” since the accused products were already accused of infringing defendants’ other asserted patents in the pending litigation. Id. at 6-7. Judge Thynge also found that inclusion of the newly-added patent in the pending litigation would not cause undue delay since no scheduling order had been entered and discovery was in its early stages. Id. at 7. Finally, the court found that there was no evidence to support a finding that defendants acted in bad faith when moving to add the newly-acquired patent. Id. at 8.