Narrowing the Disclaimer Doctrine: Federal Circuit Cabins the Reach of Disclaimers in the IPR Context


The United States Court of Appeals for the Federal Circuit recently affirmed three Inter Partes Review (IPR) final written decisions of the U.S. Patent Trial and Appeal Board (“the Board”) where the Board concluded that petitioner, Trend Micro. Inc. (“Trend”), had shown the challenged patent claims in patentee, Cupp Computing AS’s (“Cupp”), U.S. Patents Nos. 8,631,488 (“’488 patent”), 9,106,683 (“’683 patent”), and 9,843,595 (“’595 patent”), unpatentable as obvious over two prior art references.1 Setting a new precedent with respect to claim construction, the Federal Circuit held that although a patentee’s clear and unmistakable disavowals of claim scope during an IPR proceeding can narrow the scope of the claims, such a statement serves to narrow the claims only in subsequent proceedings—not in the IPR proceeding during which the statement is made.2

Cupp contended that the PTAB erred when it rejected Cupp’s disclaimers in the IPR.3 The Board did not find this argument persuasive and concluded that it could ignore the patentee’s disavowal in construing the claims.4 The Federal Circuit agreed with the Board.5

I. Introduction

Each of the three patents at issue share a common name and priority date and address the problem of malicious attacks aimed at mobile devices.6 The patents concern methods for waking a mobile device from a power-saving mode and then performing security operations on the device, “such as scanning a storage medium for malware, or updating security applications.”7

The issue on appeal to the Board’s determination related to the precedential decision is one of claim construction.8 Specifically, each independent claim in the three patents includes the limitation “the mobile device having a mobile device processor different than the mobile security system processor.”9

II. Background

In March 2019 Trend petitioned the Board for an IPR of several claims in each of the ’488, ’683, and ’595 patents arguing that the claims were unpatentable as obvious.10 Trend presented two pieces of prior art contending that either could be individually relied upon to show the challenged claims would have been obvious, including the claims’ security processor limitation.11 In response, Cupp asserted “the security system processor limitation required that the system processor be “remote” from the mobile device processor,” and neither of the prior art references disclosed that limitation.12 Cupp attempted to disclaim alternative interpretations, limiting the claim scope to get around the prior art and dictate the Board’s construction in the IPR. The Board rejected Cupp’s argument for a narrow construction based on Cupp’s allegedly disclaiming statements, and—under the Board’s construction—found the claims obvious over the prior art.13

III. The Appeal

The Federal Circuit affirmed.14 Cupp contended the Board erred by rejecting CUPP’s disclaimer in the IPRs themselves, disavowing a security system processor embedded in a mobile device.15 The Board concluded that it could ignore this disavowal in construing the claims.16 In agreeing with the Board, the Federal Circuit stated, “we now make precedential the straightforward conclusion we drew in an earlier nonprecedential opinion: [T]he Board is not required to accept a patent owner’s arguments as disclaimer when deciding the merits of those arguments.”17

IV. Discussion

The Federal Circuit explained, “a rule permitting a patentee to tailor its claims in an IPR through argument alone would substantially undermine the IPR process.”18 Its decision was motivated by the congressional intent in creating the IPR process.19 The Federal Circuit stated, “Congress designed inter partes review to “giv[e] the Patent Office significant power to revisit and revise earlier patent grants,” thus “protect[ing] the public’s paramount interest in seeing that patent monopolies are kept within their legitimate scope.”20 The Federal Circuit warned that if patentees could alter their claims through argument in an IPR, they would frustrate the Patent Office’s power to “revisit” the claims it granted.21

The Federal Circuit clarified its holding, stating that “a disclaimer in an IPR proceeding is binding in later proceedings, whether before the PTO or in court.”22 The decision emphasized that this ruling is only that a “disclaimer is not binding on the PTO in the very IPR proceeding in which it is made, just as a disclaimer in a district court proceeding would not bind the district court in that proceeding.”23

The Federal Circuit also explained that Cupp’s proposed rule would render the IPR claim amendment process unnecessary.24 Congress created a specialized process for patentees to amend their claims in an IPR.25 Under Cupp’s proposal, this process is rendered unnecessary because the same outcome could be achieved by disclaimer.26

The IPR process allows petitioners to challenge existing patent claims under §§ 102 or 103 of the Patent Act, based on prior art patents and/or printed publications. The Federal Circuit recognized that if patentees were able to modify claim language by disclaimer alone, of the patentee could evade scrutiny for compliance with other patentability requirements, such as § 101.27 The Federal Circuit found this potential for gamesmanship to be contrary to the public-protecting amendment process, which allows the Board to consider a proposed amended claim’s compliance with all patentability requirements before allowing a patent to be amended during an IPR.28 Thus, “disclaimers in an IPR proceeding are not binding in the proceeding in which they are made.”29

V. Takeaway

Going forward, a patentee’s disclaiming statements during IPR proceedings will apply only to subsequent proceedings.  Should a patentee want the Board to consider the patentability of a claim of narrower scope than the issued claims, the patentee will have to rely on the amendment process.

1 Cupp Computing AS v. Trend Micro Inc., No. 20-2262 (Fed. Cir. Nov. 16, 2022) (“Slip Op. _”), available at
2 Id. at 11.
3 Id. at 10.
4 Id. at 10.
5 Id. at 10-12.
6 Id. at 2.
7 Id.
8 Id.
9 Id. at 3 (referencing language illustrative in the ’488 patent, col. 30, ll. 37–40 & col. 31, ll. 10–13 & col. 32, ll. 18– 20;’595 patent, col. 31, ll. 25–26 & col. 32, ll. 44– 46; ’683 patent, col. 30, ll. 37–40 & col. 31, ll. 5–7 & col. 32, ll. 15–18).
10 Id. at 4.
11 Id.
12 Id.
13 Id.
14 Id. at 10.
15 Id.
16 Id.
17 Id. at 11 (internal citations omitted).
18 Id.
19 Id.
20 Id.
21 Id.
22 Id. (referring to Aylus Networks, Inc. v. Apple Inc., 856 F.3d 1353, 1361 (Fed. Cir. 2017)).
23 Id.
24 Id.
25 Id.
26 Id. (citing 35 U.S.C. § 316(d)).
27 Id.
28 Id.
29 Id. at 13.