Squires Orders Rehearing to Address Obviousness-Type Double Patenting

On March 5, 2026, USPTO director John Squires granted rehearing sua sponte to review a Patent Trial and Appeal Board (PTAB) decision denying a Request for Rehearing in Ex Parte Baurin.¹ The review will be conducted by an Appeals Review Pannel (ARP) and will focus on the PTAB’s reversal of the rejection of all claims for obviousness-type double patenting (OTDP) by finding that the reference patent was not a proper OTDP reference.²

The patent examiner rejected all claims of U.S. Patent Application Ser. No. 17/135,529 (the ’529 application), which is generally directed to dual variable region antibody-like binding proteins, on the basis of OTDP.³ The applicant appealed, arguing that the examiner’s rejection was in error because the reference patent did not qualify as a OTDP reference as it has a later filing date than the application at issue and expires later than any patent claim that would issue from the application at issue.²

The’529 application had an effective filing date of March 28, 2012, and was actually filed on December 28, 2020.³ Due to a terminal disclaimer, any patent resulting from the ’529 application would expire on March 28, 2032.⁴ The reference patent had a filing date of April 13, 2017 and, due to 70 days of patent term adjustment, was set to expire June 22, 2037.⁵ The PTAB determined that “the application at issue here was filed before the application leading to the [reference] patent, and was published well before the earliest effective filing date of the [reference] patent.”⁶

The PTAB analogized the present case to Allergan USA, Inc. v. MSN Labs. Priv. Ltd., which held that “a first-filed, first-issued, later-expiring claim cannot be invalidated by a later-filed, later-issued, earlier-expiring reference claim having a common priority date.”⁷ The PTAB explained “that is so because the first filed patent does not extend or prolong the monopoly beyond the period allowed by law; put differently it is not a ‘second, later expiring patent for the same invention.’”⁸

While acknowledging that the facts of the present case were different, the PTAB relied on Allergan to determine that the ’529 application “is not a second, later expiring patent for the same invention as the [reference] patent, and as such does not extend a period of exclusivity on the claimed subject matter.”⁹ The PTAB then determined that the reference patent was not a proper OTDP reference, and reversed the examiner’s rejections.¹⁰

In a footnote, the PTAB also dismissed the examiner’s arguments regarding a need to file a terminal disclaimer due to a risk of separate ownership as “immaterial where the [reference] patent is not a proper nonstatutory double patenting reference.”¹¹

Following the PTAB’s reversal, the examiner filed a request for reconsideration, arguing “that the decision misapprehends the holding of [Allergan], the decision is not consistent with USPTO guidance in MPEP §§ 804 and 804.02, and the conclusion ‘that the risk of separate ownership is ‘immaterial’ is not supported by case law or USPTO guidance.’”¹⁴

The examiner argued that Allergan “is limited to an ODP analysis which takes into consideration only the actual filing dates of the alleged reference patent and the patent or patent application at issue to determine what patent is the first patent of the patent family.”¹⁵ Notably, the ’529 application has an effective filing date prior to the date of the reference patent, but an actual filing date after the date of the reference patent. The PTAB dismissed this argument, stating that Allergan “made clear that both effective filing dates and expiration dates matter in determining whether claims are proper reference patents.”¹⁶ The examiner’s arguments that “the Allergan decision is only applicable to first-issued patents in a patent family” were similarly dismissed, with the PTAB stating that “an ODP analysis seeks to determine whether a reference patent is claiming a patentably indistinct invention from the patent-at-issue and is extending or prolonging a monopoly on the invention claimed in the non-reference patent, irrespective of their position as a first patent ever in a patent family.”¹⁷

The examiner further argued that “the fact that the patents at issue in Allergan had a common priority date [] precludes [] reliance on the reasoning in Allergan.”¹⁸ The PTAB responded that “the [Allergan] court’s reasoning, which we relied upon to reach our conclusion in this case, i.e., preventing an unwarranted extension of patent term for a first-filed invention, cannot be said to be limited to situations in which the alleged reference patent claims and the claims at issue have a common priority date. . . . What we found compelling was the Federal Circuit’s position that the fundamental purpose of the nonstatutory double patenting doctrine is preventing patentees from obtaining a second filed patent on a patentably indistinct invention to effectively extend the life of a first filed patent to that subject matter.” ¹⁹ The PTAB determined that the examiner’s arguments concerning Allergan were “simply a disagreement with our conclusion” and “not a proper basis to request rehearing.”²⁰

Regarding the examiner’s arguments based on the MPEP, the PTAB stated that it “must decide cases in accordance with the law, just as our reviewing court must” and that “the MPEP is a guidance document . . . and ‘does not have the force and effect of law or the force of the rules in Title 37 of the Code of Federal Regulation.’”²¹ The PTAB went on to note that “although exact expiration dates may not be able to be determined for a pending application because PTE and PTA might be awarded after substantive prosecution before the Examiner is closed, an examiner can determine the apparent expiration date . . . i.e., 20 years from the earliest effective filing date, shortened by any terminal disclaimer in the file.”²²

Lastly, relying on In re Cellect, LLC, 81 F.4th 1216 (Fed. Cir. 2023), the examiner argued that “the risk of separate ownership as a reason to uphold the double patenting rejections.”²³ The PTAB clarified that Cellect “did not, as the Examiner suggests, hold that the risk of separate ownership is a policy reason sufficient in and of itself to support an ODP rejection irrespective of whether the references are proper ODP references”²⁴ The PTAB further differentiated from other cases relied on by the examiner and determined that “none hold that [the risk of separate ownership] is the basis for making a nonstatutory double patenting rejection.”²⁵

Finding the examiner’s arguments unpersuasive, the PTAB denied the Request for Rehearing.²⁶

Squires’s order requests briefing from the patent applicant and amici addressing “(1) the applicability, if any, of Allergan USA, Inc. v. MSN Laboratories Private Ltd., 111 F.4th 1358 (Fed. Cir. 2024), to the facts of this appeal, and consideration of what constitutes ‘first-filed’ for OTDP purposes under facts different than those presented in Allergan; (2) whether examiners should determine projected expiration dates to support OTDP rejections during prosecution; and (3) whether the risk of separate ownership and preventing potential harassment by separate owners of claims to obvious variants of an invention is an independent basis that supports an OTDP rejection during prosecution.”²⁷

The ARP’s decision may provide guidance on how the USPTO will treat OTDP references, including guidance on what counts as a “first-filed” application and whether examiners should calculate expiration dates at all during prosecution. Interested parties have the opportunity to submit amici briefs until March 27, 2026.  If the ARP ultimately finds that the OTDP rejections were proper here, it is likely that the case will be appealed to the Federal Circuit, which will then have an opportunity to provide more guidance as to the contours of the Allergan decision.