Reissue Corrects Declaration in Previous Reissue

Section 251 of the U.S. Patent Law sets out the requirements for obtaining a reissue patent and provides, in relevant part:

Whenever any patent is, through error without any deceptive intention, deemed wholly or partly inoperative or invalid, by reason of a defective specification or drawing, or by reason of the patentee claiming more or less than he had a right to claim in the patent, the Director shall, on the surrender of such patent and the payment of the fee required by law, reissue the patent for the invention disclosed in the original patent, and in accordance with a new and amended application, for the unexpired part of the term of the original patent.

In Medrad, Inc. v. Tyco Healthcare Group LP, et al. (October 16, 2006), the Federal Circuit expanded the meaning of "error" under 35 USC 251 to permit a reissue application where the defect a failure to file a supplemental declaration in a previous reissue patent that narrowed the scope of coverage and corrected inventorship:

Here, in the application for reissue that resulted in the ’648 reissue patent, preliminary amendments were submitted to add new claims directed solely to the broadened subject matter identified in the inventors’ declarations. These amendments were supported by the original reissue declaration. Later amendments, however, narrowed existing claims and corrected inventorship. Because the later amendments were not supported by the original reissue declaration, a supplemental declaration was required under 37 C.F.R. § 1.175; however, none was filed before the ’648 reissue patent issued. If the narrowing amendment had never been filed, there would have been no need under the rules to file a supplemental declaration, and the resulting reissue would not have been subject to a validity challenge for failure to file such supplemental declaration. However, by including changes to the language of the claims that narrowed the scope of coverage and by correcting inventorship, the resulting ’648 reissue patent claimed more than it had a right to claim in the patent without submitting a supplemental declaration to support the narrowing subject matter and the change in inventorship. The correction of such an error meets the express terms of section 251, and thus serves as a basis for reissue.