The Problem of Abusive Serial Challenges Using Reexaminations Needs to Be Addressed by the USPTO

The current U.S. Patent and Trademark Office (USPTO) leadership has made its position on serial patent challenges crystal clear. USPTO Director Squires warned that “even extremely strong patents” cannot survive repeated rounds of review. See NPRM Comments (10/16/2025). “Serial and parallel validity challenges remain a significant problem for the patent system.” NPRM (10/17/2025). Director Squires expressed concern about the use of serial challenges as part of an “efficient infringement” strategy: “When a large company is free to copy a patented invention because it believes it can invalidate the patent through multiple validity challenges, the large company’s other advantages, such as superior brand recognition and manufacturing scale, will often give it an edge over smaller competitors.” Id. Along the same lines, Deputy Director Coke Morgan Stewart explained that “to have a stable economy, we need a stable patent system [and] [r]epeated and expedited reconsideration of patent grants under the low preponderance of evidence standard is the antithesis of stability.” Remarks, IPO Annual Mtg., (Sept. 8, 2025).

Once again, Director Squires and Deputy Director Stewart are right on the mark. Allowing excessive serial challenges to patents is unfair to patent owners and undermines the patent system. That is the case whether the serial challenges are a series of inter partes reviews (IPRs), a series of ex parte reexaminations (EPRs), or a combination of IPR and EPR challenges.

With Director Squires reducing the number of IPRs instituted, a new playbook has emerged: If your petition for IPR is denied, just reformulate it into a request for EPR and refile it with the Office. In fact, you can literally cut and paste the art and the argument from the denied IPR petition into the request for EPR. In most cases, the Central Reexamination Unit (CRU) will grant the request for EPR and institute a new proceeding even though an IPR petition presenting the same or overlapping prior art was denied. If a denied IPR petition is just a rough draft for a reexamination request, then the Director’s policies on serial challenges have a big loophole.

How can this be? One significant problem is that the CRU is not vigorously enforcing Section 325(d), which gives the Office authority to deny a request for reexamination or IPR if “the same or substantially the same prior art or arguments previously were presented to the Office.” The Office’s authority to deny EPRs under 325(d) was confirmed by the Federal Circuit. In re Vivint, Inc., 14 F.4th 1342, 1354 (Fed. Cir. 2021) (35 U.S.C. § 325(d) “applies to both IPR petitions and requests for ex parte reexamination”). Petitions challenging EPRs under Section 325(d) are typically decided by the Office of Patent Legal Administration (OPLA). As of early February 2026, OPLA had granted only four petitions to deny/terminate an EPR under Section 325(d), while denying over 150 petitions.

Plainly, the problem of serial EPRs following failed IPR challenges needs the attention of the Director before it gets out of control. A review of recent cases indicates that it is becoming a systemic problem.

Amazon v. Croga Innovations

Patent Owner Croga Innovations is the owner of U.S. Pat. No. 10,601,780, which is a cybersecurity patent for protecting a computer from malware originating from the Internet. The ’780 Patent has been subjected to six challenges—four IPRs and two EPRs.

Amazon petitioned for IPR in April 2025 (IPR2025-00884) based on one prior art ground. The decision issued by Acting Director Stewart in September 2025 denied institution. After setting the Fintiv factors aside because they were neutral, Director Stewart stated: “However, this is the fourth petition for inter partes review involving the challenged patent.” She added: “Furthermore, an ex parte reexamination has been ordered on the challenged patent, and … [i]t is not an appropriate use of Office resources to review a patent in two separate, concurrent Office proceedings.” Decision, Paper 9 (9/3/2025), at *2-3.

Plainly, Acting Director Stewart’s finding was that the patent had already been subjected to too many serial challenges through a combination of IPRs and EPRs.

What did Amazon do in response to the Director’s decision? Three months later, Amazon repackaged the unsuccessful IPR petition into a request for EPR resubmitted to the CRU (No. 90/015,746). The request presented the same prior art and same arguments as the denied IPR petition.

The result: the CRU examiner granted the EPR request to initiate a new proceeding even though (1) it was a copycat of an IPR petition that the Acting Director had already admonished as involving too many serial challenges against the patent, and (2) granting the EPR request disregarded the Director’s instruction that “[i]t is not an appropriate use of Office resources to review a patent in two separate, concurrence Office proceedings.”

Patent Owner Croga responded on February 6, 2026, by filing a etition for the Director to intervene and terminate Amazon’s EPR proceeding under Section 325(d). This is a test case for USPTO leadership to intervene to stop the emerging misuse of serial challenges, including EPRs repackaged from denied IPRs.

BMW v. Foras Technologies

Patent Owner Foras Technologies is the owner of U.S. Pat. No. 7,624,302, which involves techniques for computer systems to recover when dual core processor pairs lose lockstep. The ’302 Patent has been subjected to three separate challenges—one IPR and two EPRs.

The ’302 Patent emerged from a first EPR (No. 90/019,243) initiated by Unified Patents with all challenged claims confirmed in a reexamination certificate on August 27, 2024.

Scarcely before the ink dried on the reexamination certificate, BMW initiated an IPR on August 30, 2024, challenging the ’302 Patent in IPR2024-01347 based on two prior art grounds. The Board issued an order in March 2025 instituting the -01347 IPR.

Then BMW decided to hedge its bet by filing a request for EPR on the same two prior art grounds and, on top of that, to file the request for EPR in November 2025 while BMW’s IPR was still pending. The tactic worked because the CRU examiner granted the request to initiate the new EPR proceeding even though there was an ongoing IPR evaluating identical grounds (90/015,657).

Less than six weeks after the EPR request was granted, the PTAB issued a decision in the IPR on March 7, 2026 that confirmed all claims of the ’302 Patent as patentable.

At present, we have an untenable situation where the Board issued an IPR decision confirming all claims as patentable, and yet there is an active EPR on the same patent and on the very same grounds.

One would expect that the patent owner will file a petition to the director to terminate this EPR. But they shouldn’t have to—the CRU should have never instituted this duplicative EPR in the first place.

So, here we have an even more aggressive playbook, which is to file a duplicative EPR even before the pending IPR is decided. This kind of gaming of the patent review process should not be tolerated by the Office.

Samsung v. Pictiva

Pictiva Displays International is the owner of U.S. Pat. No. 8,314,547, which is directed to organic light emitting diode (OLED) technology and has been found to cover certain Samsung OLED products. The ’547 Patent has been subjected to four separate challenges from Samsung—two EPRs, an IPR, and a jury verdict finding the claims valid.

After Pictiva filed suit to enforce the ’547 Patent, Samsung filed a petition for IPR (IPR2024-00855) in May 2024 that was denied in November 2024, in a decision finding, in part, that “Petitioner did not show compelling merits of unpatentability.” In November 2025, a jury issued a verdict that Samsung had not proven the claims of the ’547 Patent to be invalid and awarding substantial damages for infringement.

Before trial, and after losing the IPR, Samsung also initiated an EPR proceeding (No. 90/019,921) in April 2025 against the ’547 Patent. On December 30, 2025, the USPTO issued a Notice of Intent to Issue a Reexamination Certificate (NIRC) confirming all challenged claims of the patent.

What did Samsung do? Two days before the USPTO issued the certificate confirming patentability in the first EPR on February 19, 2026, Samsung filed a request for a second EPR (No. 90/015,967) on February 17, 2026.

Once again, we have a party using the playbook of filing repeated IPRs and EPRs in a manner that undermines quiet title of the patent and that seeks to keep the patent in perpetual limbo at the Office.

This practice is not remotely fair and is the kind of serial patent challenging that current USPTO leadership has sought to eliminate. Further, Congress drafted Section 325(d) of the America Invents Act (AIA) for the express purpose of giving the Office the authority to deny cumulative requests for EPRs (in addition to IPRs) because “the Patent Office has indicated that it currently is forced to accept many requests for ex parte [] reexamination that raise challenges that are cumulative to or substantially overlap with issues previously considered by the office,” as stated by Senator Kyl. See 157 Cong. Rec. S1376 (Mar. 8, 2011).

Samsung already had a full opportunity to challenge the ’547 Patent—in court and also before the Office through both an IPR and an EPR. Allowing Samsung to challenge the patent again through another EPR—a fourth bite at the apple—is not fair to the patent owner, is not good for the U.S. patent system, and is not good for our economy.

Looking Ahead

The Director has spoken forcefully about the need for stability, fairness, and the protection of strong patents from unfair serial challenges. The outcome of unfair serial EPR/IPR challenges such as those outlined above will tell us whether those principles have teeth, whether they apply across the entire post-grant landscape or only in the IPR proceedings where the Director personally reviews institution decisions.

The answer will define whether the post-grant process serves its intended function as a legitimate mechanism for correcting genuine errors, or whether it becomes an unregulated additional bite at the apple for challengers who have already had multiple bites through prior IPR petitions and jury verdicts.

What happens next will set precedent that shapes the behavior of every patent challenger weighing an EPR filing after a denied IPR. If the Director intervenes and rejects these cumulative EPR proceedings, challengers will think twice before recycling a rejected IPR petition into a reexamination request. If not, the playbook is written, and the EPR backdoor will be wide open.

The Director has the authority to act. The facts demand it. And the integrity of the post-grant challenge system may depend on it.

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Author: merzavka
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