Judge Andrews Adopts Magistrate Judge Recommendation to Dismiss Claim on Grounds of Claim Preclusion

November 11, 2022

Publication| Intellectual Property

In Sanofi-Aventis U.S. LLC v. Apotex Corp., No. 20-804-RGA (Sept. 15, 2022), Judge Andrews adopted the recommendation of Magistrate Judge Hall that claim preclusion should bar the plaintiff’s assertion of infringement of one of the asserted patents.  The parties had litigated the patent at issue in an earlier case, after which the plaintiff had amended claims of that patent during an inter partes review proceeding. 

The plaintiff argued that the magistrate judge erroneously concluded that this suit and the earlier litigation between the parties were based on the same claim (a requirement for claim preclusion), contrary to the Federal Circuit’s holding in Senju Pharmaceuticals Co. v. Apotex Inc., 746 F.3d 1344 (Fed. Cir. 2014), that not all narrowed patent claims automatically amount to the same cause of action as their original, unamended versions.  Judge Andrews disagreed, noting that the recommended finding was based on the insignificant differences in scope between the original and amended claims, in addition to finding that the amended claims were narrower. 

The plaintiff also objected to the recommended finding that the amended claims were indeed narrower.  Judge Andrews found that the added limitations (for a premedication routine and to avoid prior art) were necessarily narrowing, and that adding a limitation to avoid prior art does not in itself create a new cause of action.

Finally, the plaintiff argued that claim preclusion did not apply because in the earlier case the plaintiff had withdrawn before trial those claims that were subsequently amended and asserted here, such that they formed no part of the judgment.  Judge Andrews stated, however, that claim preclusion also bars claims that could have been asserted, not just those that were asserted. 

The decision is available here.     

Key Point:  Judge Andrews stated that a “detailed factual analysis” of the materiality of the amendments is unnecessary for the claim preclusion inquiry if it is clear that the amended claims are largely the same as the original claims but with additional limitations added to avoid prior art.

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