D. Mass. Patent Litigation Update: April 2026

This is part of a series of articles discussing recent orders of interest issued in patent cases by the United States District Court for the District of Massachusetts.

In Maquet Cardiovascular LLC v. Abiomed, Inc., No. 1:17-cv-12311-FDS, Judge Saylor granted-in-part and denied-in-part Plaintiff’s motion for partial summary judgment on Defendant’s affirmative defense of prosecution laches.

This is the second lawsuit between the parties involving intravascular blood pumps, and one asserted claim recited a “pigtail shaped distal tip.” The pigtail feature was originally described in an earlier patent application that was incorporated by reference into a PCT application but was never directly mentioned in the PCT application itself or in any of the continuation applications that followed over the next 15 years. The earlier application was later abandoned and never published. Plaintiff amended a then-pending continuation to claim the pigtail only after litigation with Defendant had begun.