Nine Months Means Nine Months: Director Squires Closes the PGR Joinder Back Door

On September 24, 2026, USPTO Director John Squires issued a decision in Biocon Biologics, Inc. v. Regeneron Pharmaceuticals, Inc., PGR2026-00039 (Paper 18). The decision holds that a would-be joining party cannot use the Board's joinder rule to get around the statutory nine month deadline for post-grant review. Biocon's petition against Regeneron's U.S. Patent No. 12,168,036 was denied without reaching the merits. The Director's written explanation followed an August 6, 2026 notice denying institution.

The challenged patent issued December 17, 2024. The first petitioner filed its PGR petition (PGR2025-00085) on September 17, 2025, which was the last day of the nine month window. The Board instituted review on March 3, 2026. Biocon, the second petitioner, filed its own petition challenging claims 1 through 38 on April 2, 2026, along with a motion to join the first proceeding. That filing came within one month of institution, but well over a year after the patent issued.

Biocon relied on 37 C.F.R. § 42.222(b), which permits joinder requests "no later than one month after the institution date of any post-grant review for which joinder is requested." The patent owner responded that the petition was time barred. It argued that reading the rule to allow joinder past nine months "would render that regulation invalid as contrary to the plain text of 35 U.S.C. § 321(c)."

The Director’s Decision

The Director sided with Regeneron holding that “the Petition is barred by § 321(c).”

Director Squire’s analysis is based on Section 321(c), which provides that a PGR petition "may only be filed not later than the date that is 9 months after the date of the grant of the patent." The joinder provision, § 325(c), lets the Director consolidate reviews only when "more than 1 petition for a post-grant review under this chapter is properly filed." The Director read "properly filed" to mean compliance with every statutory filing requirement, including the nine month deadline. As he put it, "the statutory authorization for joinder under § 325(c) does not provide an exception to the nine-month statutory bar."

Biocon argued that the Director has broad discretion and that joinder would promote efficiency. The Director accepted the premise and rejected the conclusion: "I agree that my institution discretion is broad. But § 325(c) provides no exception to the time period in which a petition for post-grant review may be filed." He also made clear which authority controls: "The board rule on which Petitioner relies cannot override a clear statutory requirement."

Why the Result is Different with IPRs

In an IPR, Congress wrote an express carve out: the last sentence of 35 U.S.C. § 315(b) states that its one year time limitation "shall not apply to a request for joinder under subsection (c)." That exception is why late IPR petitioners routinely join instituted proceedings. The PGR chapter contains no analogous language in § 321(c) or § 325(c). Biocon was asking the Office to create by regulation an exception that Congress wrote into one chapter of the AIA and left out of the other. That argument was always vulnerable, and the Director's refusal to stretch the rule fits the current Office's text focused approach.

Practical Guidance From the Decision

Footnote 2 of the Decision contains the most useful practical instruction. The Director observed that § 42.222(b) "provides only a deadline for a request for joinder," not a license to file late. He then advised: "Given the limited time frame for filing a request for post-grant review, parties should consider filing their petition and motion for joinder before a decision on institution in the lead case."

Takeaways:

1. The nine month bar is absolute for PGR. Joinder does not extend it, and the one month rule in § 42.222(b) operates only within the statutory window.
2. Me too PGR strategies must be timely. A party that wants to ride an existing PGR must file its own petition within nine months of grant, even if the lead case has not yet been instituted.
3. Watch the calendar in biosimilar and pharmaceutical disputes. Multiple challengers frequently target the same patents. Companies that wait to see whether a competitor's PGR gets instituted will usually find the window closed.
4. Late challengers are pushed to IPR or district court. Once nine months pass, the only USPTO route is IPR, which is limited to § 102 and § 103 grounds based on patents and printed publications. Written description, enablement, and § 101 challenges are unavailable there.
5. The Director is enforcing statutory text over Board rules. Efficiency arguments will not rescue a filing the statute forbids.

Biocon Biologics, Inc. v. Regeneron Pharmaceuticals, Inc., Case No. PGR2026-00039, Paper 18 (PTAB Sept. 24, 2026) (Director Squires).

The author is a patent trial lawyer and member of Stradling’s IP Litigation and PTAB Trial Group. Stradling represents inventors, patent owners, and technology companies in patent licensing and litigation in U.S. District Courts and before the United States Patent and Trademark Office, including IPRs and EPRs. Whether pursuing patent violations or defending infringement claims, Stradling’s IP lawyers are aggressive and effective advocates for our clients. For more information contact Greg Cordrey at (949) 725-4151 or GCordrey@stradlinglaw.com.