The Federal Circuit held that the PTAB erred by declining to apply the doctrine of prosecution disclaimer in an IPR.
If, during prosecution of a patent, the patent applicant makes a clear and unambiguous statement limiting the scope of the claims, the applicant disclaims the subject matter that would otherwise fall within the scope of the claims had the statement not been made. The doctrine of prosecution disclaimer prevents a patentee from obtaining the patent by arguing that the claim scope is narrow and then arguing that the scope is broader when enforcing the patent. Recently, the Federal Circuit concluded that the PTAB erred because it did not apply the doctrine of prosecution disclaimer in an IPR.
The claims at issue in Arendi S.A.R.L. v. Google LLC, Case No. 2016-1249 (Fed. Cir. Feb. 20, 2018) related to a method of information handling in which (1) information, such as a name or address, is identified in a document, (2) a database is searched for related information, and (3) the retrieved information is displayed and entered into the document–all on a single command from a user.
During prosecution of the patent, the applicant conducted an examiner interview for which an Interview Summary was filed. The Interview Summary stated:
Applicant’s representative discussed the differences between the Tso and Borovoy references and the present invention. For instance, it was pointed out that in the Tso reference, the user must select the text string to be processed, whereas in the present invention, the user does not have to select the text string to be analyzed. Applicant’s representative may submit an After-Final Amendment that amends the independent claim to include this difference.
After the interview, the independent claim was amended to include “a single entry execute command and analysis.” Along with the claim amendment, the applicant made the following statement, with the underlining made by the applicant:
During the discussion [with the examiner on October 17, 2000], it was noted that columns 4–5 of Tso teach a user selecting a text string to be processed by clicking on the text string using various selection means. In this respect, the present invention does not require the user to select a text string to be processed since it functions automatically upon a single click of an input device, such as a button, menu item, etc.
The examiner then issued a Notice of Allowance, which included the following reasons for allowance:
[I]n Tso, the text string to be processed is determined by the current cursor position, as specified by the user [see col. 4, line 31 to col. 5, line 67], whereas the present invention “does not require the user to select the text string to be processed since it functions automatically upon a single click of an input device” to determine if the first information is contained within the document.
In the IPR, Arendi argued that the amendment and statements above constituted prosecution disclaimer and that the claims could not be construed to cover a system in which the user selects information to be searched.
The PTAB rejected Arendi’s argument. The PTAB concluded that the the examiner’s statements in the Reasons for Allowance did not result in prosecution disclaimer because “[i]t is the applicant, not the examiner, who must give up or disclaim subject matter that would otherwise fall within the scope of the claims.” Accordingly, the PTAB found that a prior art reference in which the user selected information to be searched disclosed the claimed subject matter and invalidated the claims.
On appeal, the Federal Circuit held that the PTAB erred by failing to give credit to the amendment and the arguments the applicant made during prosecution. “Here the applicant amended the claims and explained what was changed and why, and the examiner confirmed the reasons why the amended claims were deemed allowable.” Thus, the Federal Circuit concluded that the Applicant’s amendment and statements during prosecution amounted to prosecution disclaimer and reversed the PTAB’s claim construction.
However, the PTAB made an alternative ruling of unpatentability in which the PTAB assumed that claim scope was disclaimed during prosecution. The Federal Circuit found the PTAB’s alternative ruling to be supported by substantial evidence. Accordingly, while Arendi won its appeal on the claim construction issue, the invalidity of the claim was affirmed based on the PTAB’s alternative ruling.
The takeaway from this case is that prosecution disclaimer can apply in an IPR. Although the PTAB gives claims of an unexpired patent “the broadest reasonable interpretation in light of the specification,” it is essential that the prosecution history also be consulted when construing the claims.