Patents Post Grant Blog

On March 15, 2010, an expanded BPAI panel that included Chief APJ, Michael Fleming and Vice Chief APJ, Allen MacDonald rendered a decision on rehearing of an expired patent of the infamous Ronald A. Katz Technology Licensing L.P portfolio. The rehearing addressed the standard for claim construction in expired U.S. Patent No. 5,561,707. A copy of the decision is found (here).

The original BPAI decision contained a statement that, in construing the claims of an expired patent during a reexamination proceeding, “the claims will not be narrowed by interpretation not required by the claim language.”  The expanded BPAI panel clarified the statement made in the original panel decision by stating that “[i]t does not say that the claim terms cannot be interpreted using different words or limit the sources of claim meaning.”

The expanded panel agreed that Ex parte Papst-Motoren, 1 USPQ2d 1655 (BPAI 1986) “sets forth the proper standard for claim construction of claims of an expired patent in a reexamination proceeding… claims should be so construed, if possible, as to sustain their validity.” In their opinion, the panel noted that this key statement was not an indication that an expired patent claim is to be accorded any meaning possible to maintain validity. Instead, it was explained that this statement was conveying the concept that the broadest reasonable interpretation was not to be used. To this end, the panel elaborated on the principles followed in interpreting claims of an expired patent by stating that ” a patentee is entitled to rely on any of the various intrinsic and extrinsic sources of claim meaning discussed in Phillips [v. AWH Corp., 415 F.3d 1303, 1327 (Fed. Cir. 2005) (en banc)] …, including prosecution history of the original patent…since patentee may not amend.” They emphasized that “the USPTO always considers the specification.”

However, the expanded BPAI cautioned that “the goal of claim construction is to determine what a claim means from the various sources of intrinsic and extrinsic evidence without regard to its possible invalidity.” While prosecution disclaimer made during the prosecution of the original patent may be considered, prosecution disclaimer made during a current reexamination will not be considered in interpreting the meaning of claims of an expired patent.

The expanded BPAI panel maintained that the appealed claims were properly construed by the original panel, because “Appellant’s interpretation required reading limitations into the claims that were not required by the ordinary and customary meaning of the terms or specification [as they would have been understood by a person of ordinary skill in the art.]”

While this decision should be comforting to patent owners defending their expired patents in reexamination, the decision leaves open the question as to whether the statutory presumption of validity should also apply in such circumstances as amendment is no longer possible once a patent expires. The expanded panel takes a dim view of interpreting claims of expired patents narrowly to avoid invalidity and places the burden of proof on the patentee to show how an argued narrower claim construction is supported by the evidence. If such is the case,  it is of heightened importance to present declaration evidence during reexamination. For example, declaration evidence submitted under 37 C.F.R. § 1.132 in reexamination may aid in demonstrating to the Office how claim terms should be properly construed as understood by a person of ordinary skill in the relevant art at the time the invention was made, in the context of the specification and prosecution history of the original application.