United States: Precondition Of "Error" For Reissue Requires Allegations Of Deficient Or Mistaken Understanding

In In re Dinsmore, No. 13-1637 (Fed. Cir. June 10, 2014), the Federal Circuit affirmed the Board's decision rejecting a reissue application for U.S. Patent No. 7,236,568 ("the '568 patent") for failure to identify an "error" within the meaning of 35 U.S.C. § 251.

The '568 patent issued on June 26, 2007, listing Mark Dinsmore and David Caruso as inventors and twX, LLC, as the sole assignee.  During the prosecution, the examiner rejected all filed claims based on several prior art patents and rejected claims 1 and 18-20 (issued claims 1, 16, 17, and 21) for obviousness-type double patenting over claims of U.S. Patent No. 6,658,086 ("the '086 patent"), which listed Dinsmore as the sole inventor and a firm called Carl Zeiss as the sole assignee.  In response, the applicants narrowed the claims to overcome the prior art rejections and filed a terminal disclaimer over the '086 patent, stating that "any patent so granted on the instant application shall be enforceable only for and during such period that it and the prior ['086] patent are commonly owned."  Slip op. at 3 (citation omitted). 

The applicants applied to reissue all claims of the '568 patent under § 251, seeking to remove the recorded terminal disclaimer and without substituting or amending any of the claims.  The applicants identified the error upon which reissue would be based as "inadvertently and without deceptive intent fil[ing] a Terminal Disclaimer over [the '086 patent], which was not commonly owned by the owners of [the '568 patent] currently at issue."  Id. (second and third alterations in original) (citation omitted).  The examiner denied the application for being based on a defective declaration because the error was not an error upon which reissue can be based.  The applicants submitted two additional reissue declarations, amending the claimed error to be allowance of the '568 patent "based on an ineffective, invalid terminal disclaimer" that "renders the ['568] patent unenforceable."  Id. at 5 (citation omitted).  The examiner rejected both applications because the declarations failed to identify an error that could support reissue.  The applicants appealed to the Board.  The Board affirmed the examiner's rejections because "voluntary and intentional filing of a terminal disclaimer to overcome a non-statutory obviousness-type double patenting rejection . . . is not an 'error' correctible by reissue under 35 U.S.C. § 251."  Id. (quoting Ex parte Dinsmore, No. 13-6879, 2013 WL 5274029, at *9 (P.T.A.B. June 3, 2013)). The applicants appealed.

On appeal, the Federal Circuit affirmed the Board's determination that the terminal disclaimer in this case was not an error correctable by reissue.  The Court first rejected the applicants' argument that because the '568 and '086 patents had never been commonly owned, the terminal disclaimer was either ineffective or invalid.  The Court reasoned that the terminal disclaimer was effective because it stated that the '568 patent will not be enforced except when commonly owned with the '086 patent, which is a clear statement that can readily be given effect.

"On the record of this case, applicants are ultimately seeking simply to revise a choice they made, not to remedy the result of a mistaken belief.  Theirs is not an error remediable under the reissue statute."  Slip op. at 11.

The Court also noted that the terminal disclaimer was valid because the applicants did not identify anything missing that was required as part of the disclaimer or that the disclaimer included anything that was forbidden.  The terminal disclaimer, as filed, overcame the obviousness-type double patenting rejection.  The Court further explained that the terminal disclaimer also ensured that multiple infringement suits could not be filed by different assignees for the same technology by promising that the '568 patent would not be enforceable if it was ever separately owned from the '086 patent. 

The Court next explained that the applicants' argument was "that the disclaimer was 'ineffective' in the sense that it did not produce a patent they could actually enforce by themselves."  Id. at 8.  The Court reasoned, however, that even if the inability to enforce the '568 patent produced by the terminal disclaimer constitutes inoperativeness, the applicants had not identified a "cognizable false or deficient understanding of fact or law" underlying the choice to file the disclaimer.  Id.  The Court then explained that not every choice that produces inoperativeness or invalidity under § 251 can qualify for reissue—only choices based on "error" count.  Id.  The Court observed that the applicants did not allege or show they had any "deficient understanding" when they chose to file the terminal disclaimer, such as a mistaken belief as to the invalidity of the claims in the absence of the disclaimer, a misunderstanding about the plain meaning of the disclaimer, or a mistaken belief that the '568 patent and the '086 patent were in fact commonly owned.  The Court then held that the applicants' asserted error was not remediable under the reissue statute.

The Court next considered the applicants' argument that "a terminal disclaimer is akin to a contract" and that the disclaimer suffered from "antecedent impossibility" from a mutual or unilateral mistake.  Id. at 11 (citation omitted).  The Court rejected the applicants' argument because the applicants failed to claim the disclaimer was filed based on a mistaken belief.

Judges:  Taranto (author), Bryson, Hughes
[Appealed from Board]

This article previously appeared in Last Month at the Federal Circuit, July 2014.

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