Last week, the U.S. Court of Appeals for the Federal Circuit issued an opinion in Maquet Cardiovascular LLC v. Abiomed Inc. et al., No. 2023-2045 (Mar. 21, 2025), vacating and remanding a district court judgment of non-infringement.
Maquet sued Abiomed and others for infringement of inter alia U.S. Patent No. 10,238,783. The ’783 patent relates to an intravascular blood pump system (for deploying a blood pump to a desired location in a patient’s circulatory system) that eliminated the need for supplemental guide mechanisms by employing “integrated guide mechanisms” located on the device itself. The district court construed certain claim terms, including “guide mechanism” and “guide wire”. To both terms the district court added certain negative limitations advocated by Abiomed and allegedly supported by prosecution history disclaimer. The parties stipulated that under the district court’s constructions Maquet could not prove infringement of the asserted claims, and the district court entered judgment accordingly. Maquet appealed.
The Federal Circuit vacated and remanded the judgment of non-infringement of the ’738 patent. As an initial matter, the Court rejected Abiomed’s invitation to affirm the judgment of non-infringement without reaching the question of claim construction. The Court noted that Maquet’s stipulation of non-infringement was specifically contingent on the Court’s ruling on the disputed portion of the claim construction and could not be properly viewed as an admission that the accused products fail to satisfy the agreed portion of the construction. The Court further declined to address other non-infringement arguments because they had not yet been presented to the district court. Turning to claim construction, the Court concluded that the district court erred in applying prosecution history disclaimer to limit the disputed claim terms. As to the “guide mechanism” term, the Court held the district court erred in finding prosecution history disclaimer because it relied “on an amendment made during the prosecution history of a different patent involving a different claim term.” The Court rejected Abiomed’s suggestion that prosecution history disclaimer can apply “despite differences in the claim language, when patents share ‘common subject matter.’” As to the “guide wire” terms, the Court held the district court erred in finding prosecution history disclaimer because there was no clear and unmistakable disavowal of claim scope. Specifically, the Court noted that an “applicant’s silence in response to an examiner’s notice of allowance will generally not rise to a clear and unmistakable claim disavowal.”


