Court Refuses to Correct Patent Error that Requires a Multi-Step Analysis to Uncover

The District Court of New Jersey declined Plaintiffs’ Vifor (International) AG and American Regent, Inc. request for judicial correction of what they argued was an obvious error in a patent related to Injectafer®.  Vifor (International) AG v. Mylan Laboratories Limited, 19-cv-13955 (D.N.J. April 26, 2021).  While Vifor may still seek correction at the USPTO, the court held that the alleged mistake in the patent’s independent claim was not the kind of obvious mistake it has the power to correct.

Vifor holds U.S. Patent No. 10,519,252 which covers an iron(III) carboxymaltodextrin complex, used in Injectafer® to treat iron deficiency anemia.  After asserting the patent against Mylan and Sandoz, Vifor sought judicial correction of an allegedly obvious error in claim 1 concerning the stated stereochemistry of the molecule.  The claim indicated the claimed molecule was the “S” enantiomer when in fact it is in an “R” configuration.

The court applied a two-step analysis from the Federal Circuit’s Novo Industries, L.P. v. Micro Molds Corp., where the first step is whether the claim makes sense as written.  If the claim makes sense, the inquiry ends (no correction).  But if not, then the error is evident on the face of the patent and the court must consider the prosecution history to see what interpretation is supported.

Here, even though both sides agreed the characterization of the molecule as being in the “S” configuration was incorrect, the court held that the stereochemical analysis required to make that determination was sufficiently complicated that a POSA would not have “easily . . . recognize[d] it” so as to understand that the claim was actually directed to the “R” enantiomer.  Instead, a “tedious, multi-step analysis requiring the manipulation of three dimensional molecular structures” was necessary to reveal the error.  And there was no “red flag” to suggest to a POSA that they should undertake such an analysis when reading the claim.  Under these circumstances, where a reading of the claim is neither unintelligible nor gives a meaning which is unknown to a POSA, the court held that judicial correction is unavailable.