Federal Circuit: Claim Amendments During IPR That Respond to Grounds of Unpatentability May Also Make Changes Unrelated to the IPR

Dec 1, 2022

Reading Time : 1 min

In American National Manufacturing, Inc. v. Sleep Number Corp, the appellant-petitioner American National argued that the PTAB erred in its application of 37 C.F.R. § 42.121 when it permitted Sleep Number to include certain claim amendments to “achieve consistency and accuracy in terminology and phrasing throughout the patent family.” Section 42.121 specifies that a motion to amend may be denied where “[t]he amendment does not respond to a ground of unpatentability involved in the trial.” In applying this regulation, the PTAB determined that any claim amended to address a ground of unpatentability could also be amended for other reasons, including potential § 101 and § 112 issues.

On appeal, American National argued the Board violated due process and the APA by allowing additional amendments in the context of an IPR. More specifically, American National argued it would be unfair and asymmetrical to allow patentees to use an IPR as a vehicle to amend claims to address § 101 or § 112 issues when petitioners cannot challenge claims on those grounds.

The Federal Circuit, however, disagreed. Citing previous decisions, the court noted that petitioners are free to challenge amended claims on grounds that go beyond § 102 and § 103, including on § 101 and § 112. Thus, it discerned no asymmetry between patentees and petitioners in the context of a motion to amend. And because each of the amended claims contained an amendment responsive to a ground of unpatentability raised in the IPR proceeding, Sleep Number’s additional amendments were not improper.

Practice Tip: For patentees facing co-pending litigation and IPR proceedings, there may be an opportunity to amend claims to defeat both the IPR petition and live defenses in the litigation. It is important, however, to weigh that value of such a result against the risk of possible invalidation or intervening rights. And, similarly, defendants considering filing an IPR petition must weigh the possibility that the Patent Owner might use a motion to amend to remedy potential § 112 deficiencies.

American National Manufacturing, Inc. v. Sleep Number Corporation, Case Nos. 2021-1321

Share This Insight

Previous Entries

IP Newsflash

November 11, 2025

The Federal Circuit recently vacated a summary judgment ruling of invalidity, holding that the district court erred in applying preclusive effect to the Patent Trial and Appeal Board’s unpatentability findings regarding other claims in the same patent. In doing so, the Federal Circuit reiterated that issue preclusion does not apply where the prior factual determinations were made under a lower standard of proof.

...

Read More

IP Newsflash

November 3, 2025

The Federal Circuit recently clarified the requirement for work disclosed in a reference to qualify as “by another” under pre-AIA Sections 102(a) and (e), holding that there must be complete inventive identity between the information disclosed in the asserted reference and the inventors named on the relevant patent. 

...

Read More

IP Newsflash

October 31, 2025

The District Court for the Northern District of California recently granted a defendant’s motion to bifurcate, ordering that issues related to PGR estoppel should be decided in a bench trial, while the remaining issues in the case should proceed to a jury trial.

...

Read More

IP Newsflash

October 31, 2025

The Northern District of Iowa recently held that a defendant’s motion for partial summary judgment of invalidity was barred after the PTAB issued final written decisions, regardless of when the motion was filed. The defendant filed its motion before the final written decisions were issued, but the court rejected the defendant’s argument that the timing of the motion insulated it from estoppel.

...

Read More

IP Newsflash

October 1, 2025

In a recent final written decision, the PTAB determined that a reference patent was not prior art, despite the petitioner’s post‑filing attempt to correct its petition. While the petitioner argued that it intended to rely on the patent application’s earlier date of publication, both the corrected petition and the expert declaration continued to reference the issued patent rather than the published application.

...

Read More

IP Newsflash

September 30, 2025

The USPTO Director recently granted a petitioner’s request for rehearing of the decision discretionarily denying institution of inter partes review, ultimately vacating the original decision, and referring the petition to the board for an institution decision.

...

Read More

IP Newsflash

September 25, 2025

In considering claims to a method of reducing cardiovascular events, the Federal Circuit held that the term a “clinically proven effective” amount did not render the claims patentable over the prior art. Specifically, the Federal Circuit held that the “clinically proven effective” amount, whether limiting or not, could not be used to distinguish the prior art because the claims also specified the exact amount of the drugs to be administered in the method. The Federal Circuit also rejected patentee’s evidence of unexpected results because that evidence was tied solely to the “clinically proven effective” limitation.

...

Read More

IP Newsflash

September 24, 2025

The Federal Circuit reversed a district court’s denial of judgment as a matter of law on non-infringement, thereby setting aside a $106 million jury verdict, after holding that prosecution history estoppel barred the patentee from asserting infringement under the doctrine of equivalents.

...

Read More

© 2025 Akin Gump Strauss Hauer & Feld LLP. All rights reserved. Attorney advertising. This document is distributed for informational use only; it does not constitute legal advice and should not be used as such. Prior results do not guarantee a similar outcome. Akin is the practicing name of Akin Gump LLP, a New York limited liability partnership authorized and regulated by the Solicitors Regulation Authority under number 267321. A list of the partners is available for inspection at Eighth Floor, Ten Bishops Square, London E1 6EG. For more information about Akin Gump LLP, Akin Gump Strauss Hauer & Feld LLP and other associated entities under which the Akin Gump network operates worldwide, please see our Legal Notices page.