USPTO Signals Stricter Stance on Patent Term in Double Patenting Cases

WASHINGTON — The U.S. Patent and Trademark Office has clarified its approach to a complex and financially significant issue for innovators, signaling that patent life extensions granted due to agency delays may be forfeited in certain common filing scenarios. A recent action by the agency's Central Reexamination Unit (CRU) in June 2026, within the case of ex parte Corteva Agriscience LLC, indicates that the USPTO will enforce a reading of patent law that could shorten the enforceable life of many patents, particularly in the pharmaceutical and technology sectors.

The decision centers on the intersection of two doctrines: obviousness-type double patenting (ODP) and Patent Term Adjustment (PTA). ODP is a long-standing legal principle designed to prevent an entity from unfairly extending its monopoly by obtaining multiple patents on inventions that are not meaningfully distinct from one another. PTA, conversely, is a statutory provision that compensates patent holders by adding extra days to a patent's 20-year term to make up for certain administrative delays caused by the USPTO during the examination process.

For decades, companies have used a strategy of filing “continuation” applications, which build upon an earlier “parent” application to protect different aspects of an invention. This common practice often leads to a family of related patents with different expiration dates. However, if a later-filed patent in the family is deemed an obvious variation of an earlier one, the USPTO will issue an ODP rejection.

The standard method for overcoming this rejection is for the patent owner to file a “terminal disclaimer.” This legal instrument ties the expiration date of the later patent to the expiration date of the earlier patent, effectively ensuring that the patent owner does not receive an improper time-wise extension of their patent rights. The central conflict arises when the later patent has been granted PTA due to USPTO delays. The question becomes whether the terminal disclaimer nullifies only the base term extension or if it also cancels out the awarded PTA.

In the Corteva reexamination proceedings, the CRU adopted the position that a terminal disclaimer surrenders any patent term that extends beyond the expiration date of the parent patent, including any PTA that has been granted. This interpretation means that even if the USPTO’s own delays entitled a patent holder to, for example, two extra years on their patent term, filing a terminal disclaimer to resolve an ODP issue would wipe out that two-year adjustment. For products with billions of dollars in annual sales, the loss of even a few months of market exclusivity can represent a substantial financial blow.

This clarification from the USPTO follows a series of contentious court battles that have created uncertainty for patent holders. The U.S. Court of Appeals for the Federal Circuit has addressed this issue in several cases, notably in the In re Cellect decisions, but its rulings have left some ambiguity that the USPTO now appears to be resolving through its examination practice. While not a new formal rule, the agency’s action in the Corteva case provides the clearest signal yet of its enforcement posture, forcing companies to confront the potential loss of valuable patent term when structuring their intellectual property portfolios.

The direct financial consequences for small and mid-sized businesses can be severe. Companies in high-tech and life sciences fields often rely on patent families to build a protective wall around their core innovations. The ability to secure PTA is a critical mechanism for recouping time and investment lost to a protracted patent examination process. The USPTO's stance effectively forces a difficult choice: either abandon potentially valuable claims in a continuation application or file a terminal disclaimer and risk forfeiting PTA, thereby shortening the commercial life of the resulting patent.

This shift necessitates a significant re-evaluation of patent strategy. Companies and their legal counsel must now more carefully weigh the benefits of filing continuation applications against the risk of ODP rejections that could neutralize PTA. This may lead to more aggressive arguments against ODP rejections during prosecution, as the once-routine filing of a terminal disclaimer now carries a much higher potential cost. It also places a premium on managing the prosecution process to minimize the initial USPTO delays that lead to the granting of PTA in the first place.

For growing companies, particularly those in technology and life sciences, this clarification from the USPTO is more than a legal nuance; it is a direct hit to asset valuation. In our experience, a robust patent portfolio is often the cornerstone of a company's value proposition during fundraising or an M&A event. Investors and acquirers scrutinize the expiration dates of key patents to model future revenue streams. An unexpected shortening of a patent's term by several years, due to this interplay between PTA and terminal disclaimers, can materially decrease a company's valuation. We have seen deals hinge on the projected period of market exclusivity.

This ruling underscores the necessity of integrating IP strategy with financial planning from the earliest stages. Proactive management of a patent portfolio is now even more critical. Businesses need to understand not just the technical strength of their patents, but also their true enforceable lifespan. This is a crucial component of our capital raising and investor strategy services, where we help clients present a clear and accurate picture of their intellectual property assets to potential partners. For guidance on how these regulatory shifts impact your company's valuation and financial strategy, contact C&S Finance Group LLC at csfinancegroup.com.

Looking ahead, the intellectual property community will be watching closely for further administrative guidance or potential appeals that could challenge the USPTO's position. In the absence of a contrary court ruling or legislative action, however, patent applicants must now operate under the assumption that a terminal disclaimer will waive any awarded PTA. This reality will shape patent filing and prosecution strategies for the foreseeable future.