Late Amendment of Contentions: Denied as to New Patent, Granted as to New Prior Art

Plaintiff's motion for leave to serve amended infringement contentions, asserting infringement of an additional patent, was denied because defendant made its source code available a month before plaintiff's supplemental contentions were due and plaintiff waited more than four months after that date to seek leave to amend its infringement contentions. "[Plaintiff] has not shown that its delay in adding [a] Patent was reasonable based on the amount of time it had to inspect [defendant's] source code." However, defendant's motion for leave to supplement its invalidity contentions was granted. "[T]he Court notes that the addition of prior art references post Markman do not have the same implications as the addition of an entirely new patent. Any potential prejudice that [plaintiff] may suffer as a result of [defendant] amending its invalidity contentions would likely arise in connection with the [upcoming] discovery deadline. This potential prejudice can easily be cured with an appropriate continuance of the discovery deadline if needed."

Sybase, Inc. v. Vertica Systems, Inc., 6-08-cv-0024
(TXED November 30, 2009, Memorandum Opinion & Order) (Davis, J.)