Claim construction decisions do not always proceed as predicted by either party, and IPR proceedings can be particularly unpredictable when it comes to construing claim terms. A recent petition for writ of certiorari to the Supreme Court, in NST Global v. Sig Sauer, provides helpful reminders regarding claim construction and limiting preambles.
History of the Case:
Plaintiff NST Global invented a firearm accessory, the "Stabilizing Brace", that allowed users to stabilize the use of a handgun by stabilizing the forearm of the user.1 NST Global was granted two patents on the invention.2 Defendant Sig Sauer obtained a license to the patents as the exclusive distributor for several years, but after the agreement ended, Sig Sauer developed its own brace.3 NST Global filed an infringement lawsuit against Sig Sauer.4 Sig Sauer subsequently filed two IPR Petitions against the patents, and the infringement suit was stayed.5 The PTAB instituted both IPRs and ultimately found certain claims patentable and certain claims unpatentable. In the Final Written Decisions, one of the reasons the PTAB found certain claims unpatentable was based on construing a preamble to be limiting.6 Both parties appealed to the Federal Circuit, and after oral argument, the Federal Circuit issued a Rule 36 affirmance of the PTAB's decision.7 NST Global filed a petition for a writ of certiorari to the Supreme Court which is currently pending before the Court.
Issues Raised:
The petition raises two primary issues: 1) what is the proper standard for construing patent claim preambles? and 2) what constitutes notice or a waiver of arguments for the PTAB to construe a claim in its Final Written Decision without argument from one or both parties? Both parties' positions on these issues will be discussed further below, as well as how they may affect decision making during patent prosecution and litigation proceedings.
1. Construing Preambles as Limiting:
In the Final Written Decisions, the PTAB found certain claims of NST's patents have preambles that are limiting on the claims.8 The claims of the patent recite:
"A forearm-gripping stabilizing attachment for a handgun, the handgun having a support structure extending rearwardly from the rear end of the handgun, the forearm-gripping stabilizing attachment, comprising:"9
The PTAB's construction found "a handgun" and "a support structure ..." as "essential structure", "necessary to give life, meaning, and vitality to the claims," and therefore the preamble is limiting.10 NST Global presented objective evidence of non-obviousness that demonstrated commercial success, copying, and licensing of its product.11 However, the PTAB rejected this evidence because NST Global did not present evidence of how many products sold included the preamble terms "a handgun" and "a support structure....".12
NST Global, in its petition to the Supreme Court, states that there is a "lack of a uniform analytical framework for preamble limitation analysis" and quotes different cases to support their position.13 For example, NST Global cites the following as different tests for determining if a preamble is limiting:
- "whether the preamble breathes life and meaning into the claims" (limiting);14
- if the preamble "recites essential structure or steps, or if it is necessary to give life, meaning, and vitality to the claim" (limiting);15
- "if the body of the claim sets out the complete invention" (not limiting);16
- if a claim "uses the preamble only to state a purpose or intended use for the invention" (not limiting);17
- "[d]ependence on a particular disputed preamble phrase for antecedent basis may limit claim scope" (limiting);18 or
- if the preamble described conventional (not limiting) or inventive uses (limiting).19
Sig Sauer counters in its opposition to the petition that NST Global's arguments regarding "the law of preambles" are incorrect.20 Sig Sauer further argues that the Supreme Court need not address "the law of preambles" because NST Global did not raise these arguments in its opening brief to the Federal Circuit.21 Instead, Sig Sauer states that the "issue of whether the [p]reambles were limiting was a consistent issue in the IPR proceedings."22 According to Sig Sauer, a contention in an IPR petition that a piece of prior art discloses the subject matter of a preamble includes a construction that the preamble is limiting.23
NST Global's petition provides a timely reminder of the need to pay attention to claim preambles whether you are a patent owner or patent challenger given the unsettled nature of the law in this area. While NST Global's list of purportedly different tests used by the Federal Circuit is not exhaustive of the cases addressing preambles as limiting in claims, applying these tests can be helpful in assessing a current patent portfolio or drafting claims during prosecution to ensure that the claims, including the preamble, only include the components of the invention that need to be protected. Practitioners should also make sure that, when either challenging or defending a patent claim, the prior art discloses the preamble of the claim.
2. Notice and Waiver of Claim Construction at the PTAB
As noted above, during the proceedings before the PTAB, Sig Sauer, as petitioner, identified where in the prior art the preambles of the challenged claims were disclosed but did not explicitly seek a claim construction of the preambles as limiting.24 NST Global, in its Patent Owner Response in the PTAB, did not dispute that the prior art disclosed the preamble.25 NST Global states in its petition for a writ of certiorari that because Sig Sauer did not construe the preambles, NST Global does "not have the burden of producing evidence on an issue until after Sig [Sauer], as the challenger, places that issue in dispute."26 In response, Sig Sauer claims that NST Global's failure to dispute that the prior art discloses the preambles constituted a waiver with respect to any argument that the preambles are not limiting.27
NST Global's position that it did not waive this claim construction issue is based on the Administrative Procedures Act ("APA") and the subsequent case law that holds that "an agency violates due process if it change[s] theories in midstream without giving respondents reasonable notice of the change."28 In the context of the PTAB and this case, this means that if the PTAB adopts a claim construction in its Final Written Decision without providing notice to either party, then the PTAB would be in violation of the APA. The question in this case is whether the PTAB, by acknowledging that NST Global did not dispute Sig Sauer's contentions, provided notice that the preamble was in dispute and that NST Global waived all arguments, including claim construction arguments, relating to the preambles by not disputing Sig Sauer's contentions? NST Global says there was no notice.
Sig Sauer, in response to NST Global's petition for certiorari, states that NST Global had notice and opportunity to respond to Sig Sauer's arguments at the PTAB.29 Sig Sauer identifies multiple points in the PTAB proceeding where NST Global could have addressed whether the preamble was limiting, such as the Patent Owner Response, the Patent Owner Sur-Reply, at the Hearing in response to either the PTAB or Sig Sauer's raising of the issue, or in a petition for rehearing after the Final Written Decision.30 Sig Sauer cites to Federal Circuit case law where a claim term at issue in the briefing and the hearing provided notice and opportunity for a Patent Owner given the "continuous focus" on the claim limitation and the opportunity for sur-reply or rehearing.31
The Supreme Court may or may not decide to address this issue, but the case does provide a helpful reminder regarding the requirements of the APA and when the PTAB cannot decide issues in an IPR. Regardless of the PTAB's compliance with the APA, this case provides useful guidance to help practitioners ensure that either Patent Owners or Petitioners in an IPR sufficiently address issues, like claim construction, that are related to the limitations and claims at issue. This case also provides a reminder regarding the various opportunities to respond to arguments during an IPR proceeding, including during a hearing where the PTAB raises an issue that may not be directly addressed by any previously filed briefs.
Footnotes
1 NST Global, LLC v. Sig Sauer, Inc., petition for cert. pending at p. 3, No. 22-1001, (filed April 12, 2023) ("Petit.").
2 Id. at 3-4.
3 Id. at 4.
4 Id.
5 Id. at 4-5.
6 Id. at 5-8; Appendix C, 30a-32a; Appendix D, 110a-112a.
7 Id. at 8-10.
8 Id. at Appendix C, 30a-32a; Appendix D, 110a-112a.
9 Id. at Appendix C, 10a.
10 Id. at Appendix C, 32a.
11 See, id. at Appendix C, 57a-63a.
12 Id. at Appendix C, 61a.
13 Id. at 20; see id. at 18-20.
14 Id. at 18 (citing Catalina Mktg. Int'l, Inc. v. Coolsavings.com, Inc., 289 F.3d 801, 808 (Fed. Cir. 2002)).
15 Catalina, 289 F.3d at 808.
16 Eaton Corp. v. Rockwell Int'l Corp., 323 F.3d 1332, 1339 (Fed. Cir. 2003).
17 Rowe v. Dror, 112 F.3d 473, 478 (Fed. Cir. 1997).
18 Catalina, 289 F.3d at 808.
19 See Petit. at 19-20 (citing Cochlear Bone Anchored Sols.AB v. Oticon Med. AB, 958 F.3d 1348, 1355 (Fed. Cir. 2020)).
20 NST Global, LLC v. Sig Sauer, Inc., opposition to petition for cert. pending at p. 17, No. 22-1001, (filed May 15, 2023) ("Opp.").
21 Id.
22 Id. at 14.
23 See id. at 13-14.
24 See Petit. at 24; see also Opp. at 13.
25 See Opp. at 15-16.
26 Petit. at 25.
27 Opp. at 16.
28 Petit. at 28.
29 Opp. at 18-22.
30 Opp. at 19-20.
31 Opp. at 18-19 (citing Intellectual Ventures II LLC v. Ericsson Inc., 686 F. App'x 900, 906 (Fed. Cir. 2017)).
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