Interpretation of statutory two-year time limit for enlarging the scope of claim in a continuing reissue application filed after the two-year window

| March 14, 2012

In re Erik P. Staats and Robin D. Lash

March 5, 2012

Panel:  Dyk, O’Malley and Reyna.  Opinion by Dyk.  Concurrence by O’Malley.


In 1999, a patent was issued to Staats (assigned to Apple Computer) based on an application for his invention regarding isochronous data transfer in a computer.  The patent discloses two embodiments.  Staats then filed a first reissue application within two years from the issue date of the patent, broadening the scope of claims related to a first embodiment.  Outside the two-year window, he further filed other broadening reissue applications as continuations.  In 2007, almost seven years after the original patent issued, the last broadening reissue application was filed, which is related to a second embodiment.  The PTO’s board held that the last continuing reissue application was not filed within the two-year window because it was not related to the first embodiment which was timely presented within the two-year window.  The CAFC reversed and remanded this case, affirming their precedent case which holds that the statutory two-year limit applies to only the filing date of a reissue application, not to the date that broadened claims are presented.


The original patent claims:

[a] method comprising:

configuring an isochronous channel within a computer system to include a linked of buffers to receive isochronous data transmitted with said computer system…

In filing the first reissue application, Staats declared that this application was for “failure to claim or to further claim subject matter disclosed in the specification pertaining to a method for handling data transmitted on an isochronous channel using a linked list of buffers…” (emphasis added).

The second continuing reissue application was filed based on the first reissue application.  The second application addressed errors related to the first embodiment using the linked list of buffers.  The second reissue application was allowed and issued in 2007, which was almost seven years after the issuance of the original patent.

Upon allowance of the second reissue application, the third continuing reissue application was filed.  This reissue application was to add new claims directed to the second embodiment disclosed in the original patent, but not claimed in the first and second reissue applications.  The second embodiment is about establishment of an isochronous channel bypassing a CPU, and thus does not require using the “linked list of buffers” for interrupting a CPU function, unlike the first reissue application explicitly requiring “a linked list of buffers”.

35 U.S.C. § 251 states: “no reissued patent shall be granted enlarging the scope of the claims of the original patent unless applied for within two years from the grant of the original patent.”

The Examiner rejected the third application under 35 U.S.C. § 251, finding that the new broadened claims were “not related in any way to what was covered in the original broadening reissue.”  Then, the PTO’s Board agreed with the Examiner’s reasoning, stating that the newly added broadened claims were in fact “directed to an invention that was independent and distinct from that claimed in the original and first reissue applications.  The Board explained that the broadening was “unforeseeable” from the original reissue application filed within two years, and the “public notice function of § 251” had not been met.

The two-year limit was originally developed from a rule of laches, the “dedication to the public could not be avoided unless the patentee proved “real inadvertence, accident, or mistake,” which “should be done with all due diligence and speed.”  The judicially-created limit was codified into section 251 in 1952.

The PTO’s Board and the CAFC did not dispute that the precedent case, In re Doll, 419 F.2d 925 (C.C.P.A. 1970) is binding here, but interpreted the statutory time-limit differently.  The Board interpretation of Doll is that the broadened claims “were related to the subject matter covered by the claims identified and broadened within the two-year window”, and therefore, “the public was adequately notified of” the later broadened claims.  Based on the facts of the “related” subject matter, the Board argued that in contrast, the claims in dispute in this case are directed to an embodiment “unrelated” to the first embodiment covered by the broadened claims identified within the two-year window.

The CAFC disagreed with the Board’s argument based on the specific facts in Doll that the later-filed broadened claims were related to the first reissue application.  Instead the CAFC noted: “[s]ignificantly, Doll itself made no distinction between related claims and unrelated claims”, and “Doll simply held that section 251’s time limit clearly applied only to the filing date of the first broadening reissue application”.  Thus, the applicant is “not barred from making further broadening changes after the two year period in the course of [the] prosecution of the reissue application.”

The CAFC criticized the PTO’s approach by stating that it “is, moreover, unmanageable”, because “[e]very claim must, by definition, be different in scope than the other claims of the patent” and because “it is difficult to distinguish one patent embodiment from another or to determine when a later claim is related to an earlier claim”, and therefore, “[a] rule requiring that the new claims be related to the previously submitted claims, or be directed to the same embodiment, would be difficult to administer in a consistent and predictable way.”

Full Decision

Patent At Issue


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