Calling a Printed Publication a “System” is Not Enough to Avoid IPR Estoppel

Jan 27, 2020

Reading Time : 2 min

On January 10, 2017, Plaintiff filed a complaint for patent infringement against Defendant. In response, Defendant filed IPR petitions against the patents-in-suit. The district court stayed the litigation pending resolution of the IPRs. After the Board issued its final written decisions in the IPRs—which invalidated only some of the patents—the court partially lifted the stay of the action as to the patents that survived the IPR. On November 12, 2019, Plaintiff and Defendant filed cross-motions for summary judgement. Among the motions was Plaintiff’s motion for partial summary judgment of no obviousness based on IPR estoppel under § 35 USC 315(e)(2).

Under § 315(e)(2), IPR estoppel applies when “(1) a final written decision is issued in an IPR; (2) the contention at issue asserts invalidity under §§ 102 or 103 based only on prior art consisting of patents or printed publications; and (3) the contention at issue either was raised or reasonably could have been raised during the IPR.”

Plaintiff argued that § 315(e)(2) applied because all of the prior art references asserted in Defendant’s expert’s report were classified as either patents or printed publications and, thus, should have been asserted in the IPR proceeding. In response, Defendant argued that each of its expert’s obviousness combinations included at least one “system” prior art reference—i.e., the Microsoft Outlook Software System reference, the Microsoft Server System reference, the Nokia 7xxx Series Mobile Phone System reference and the Pocket PC Phone System reference—which could not have been raised during the IPR proceeding because they are not patents or printed publications.

The Court agreed with Plaintiff and held that IPR estoppel applies. In doing so, the Court noted that “‘if a patent challenge is simply swapping labels for what is otherwise a patent or printed publication invalidity ground in order to ‘cloak’ its prior art ground and ‘skirt’ estoppel,’ then § 315(e)(2) estoppel still applies.” The Court explicitly rejected Defendant’s argument that using the term “system” to refer to the relevant prior art references in its invalidity contentions was sufficient to avoid estoppel. In fact, the court noted that Defendant described the alleged “system” references as “patents and publications” in its contentions and even explained that the reference names were merely a “short name” for the reference and not the actual description of the reference. As a result, the court found that Defendant relied only on printed publications in its obviousness theories of invalidity, specifically ones that “reasonabl[y] could have been raised during the IPR.” Defendant was therefore estopped under § 315(e)(2) from asserting invalidity based on obviousness.

Practice Tip: A district court defendant that wants to rely on a prior art system in order to avoid IPR estoppel should make clear in its invalidity contentions that it is relying on the actual system itself, rather than a patent or printed publication describing the system. Moreover, practitioners should take care when labeling types of prior art references, as courts may not allow labels to be swapped in order to avoid § 315(e)(2) estoppel.

Vaporstream, Inc. v. Snap, Inc., No. 2:17-cv-00220-MLH (KSx) (C.D. Cal. Jan. 13, 2020)

Share This Insight

Previous Entries

IP Newsflash

November 14, 2025

The Ninth Circuit recently reversed a district court’s decision to strike a plaintiff’s trade secret claims under the Defend Trade Secrets Act (DTSA) at the discovery stage. In doing so, the Ninth Circuit made clear that under the DTSA, whether a party defined their trade secret with sufficient particularity is a question of fact that generally does not lend itself to resolution in the absence of at least some discovery. This ruling contrasts with the California Uniform Trade Secrets Act (CUTSA), which requires a party to define their trade secrets with reasonable particularity before commencing discovery.

...

Read More

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

© 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.