PTAB challenges

Proceedings Overview

There are no AIA trial proceedings on file at the PTAB for U.S. Patent 11,566,277. For a defendant, this means the patent's validity has not been tested or affirmed in a post-grant proceeding, leaving all defensive options, including arguments based on prior art, fully available.

Strategic Summary

Based on a review of the USPTO's Open Data Portal and public search records as of May 12, 2026, U.S. Patent 11,566,277 has not been the subject of any inter partes review (IPR), post-grant review (PGR), or covered business method (CBM) proceedings.

• Claim Status: All claims of U.S. Patent 11,566,277—including independent claims 1, 14, and 21—are UNTESTED before the PTAB. No claims have been canceled or sustained through an AIA trial.

• Estoppel Landscape: For a defendant, such as Element Biosciences in the current district court litigation (10X Genomics, Inc. et al v. Element Biosciences, Inc., D. Del. 1:26-cv-00538), there is no petitioner estoppel under 35 U.S.C. § 315(e)(2). This provides maximum flexibility, as any and all grounds of invalidity that can be raised in an IPR or PGR are still available. A future petitioner would not be barred from using prior art that it "reasonably could have raised" in a prior proceeding, because no prior proceeding exists.

• Pattern Signals: The absence of PTAB challenges is a significant signal. Patents that are frequently asserted by major commercial players, like 10x Genomics, often attract IPRs from competitors or defensive aggregators. The lack of any such challenge to date suggests that the patent may not have been widely asserted prior to the recently filed litigation against Element Biosciences.

Recommended Next Steps

For a defendant facing an assertion of U.S. Patent 11,566,277, the path is clear:

• No PTAB Activity: The primary takeaway is that there is no history of PTAB litigation for this patent. This is a "clean slate" scenario. The patent has not been "hardened" by surviving a previous validity challenge at the PTAB, which can be a significant advantage.
• IPR as a Viable Defense: A defendant should strongly consider filing an IPR as a key part of its defensive strategy. All potential prior art references are available for use in a petition. Given the statutory one-year timeline for an IPR from institution to a final written decision, this can provide a faster and often more cost-effective route to a validity determination than district court litigation.
• Monitor for New Filings: Given the active litigation, it is highly probable that the defendant, Element Biosciences, will file one or more IPR petitions against this patent in the near future. Any party with an interest in this technology space should monitor the PTAB docket for such filings, as they will provide the first indication of the prior art being used to challenge the claims and the patent owner's initial defensive arguments. The statutory deadline for filing an IPR is one year from the date of service of the infringement complaint. With a service date of May 8, 2026, a petition would be due by May 2027.