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September 27, 2021

FDA Seeks to Deepen Engagement with USPTO on Pharmaceutical Patents


On September 10, 2021, the Acting Commissioner of the Food and Drug Administration (FDA), Janet Woodcock, published a letter to the US Patent and Trademark Office (USPTO) seeking increased exchange and collaboration between the two agencies relating to grants of patent rights to pharmaceutical innovations. The FDA letter was written pursuant to President Biden’s Executive Order 14036 (EO), which aims to promote competition and address drug pricing concerns. 86 Fed. Reg. 36987. Both the letter and the EO acknowledge the necessity of incentivizing innovations through the patent system, but assert that certain patent procurement strategies are employed by the brand pharmaceutical companies to improperly delay the entry of less expensive generic products. Specifically, the FDA letter expressed concern about brand pharmaceutical companies’ conduct that the agency believes could improperly delay the approval and entry of generic drugs, biosimilars, and interchangeable biological products through three alleged strategies: patent “thickets,” patent “evergreening,” and “product hopping.”

To address these strategies, FDA offers training to patent examiners on navigating and understanding FDA’s databases for uncovering potential prior art, and requests USPTO to consider increasing the time given to patent examiners for examining pharmaceutical patents. FDA further offers training to USPTO regarding patent term extension. Finally, FDA solicits USPTO’s views on limiting patent misuses and ways to optimizing the Patent Trial and Appeal Board (PTAB) framework for reviewing validity of granted patent claims.

While it is unlikely that this FDA letter alone will have any immediate impact on the USPTO’s existing patent examination framework, this letter is the latest evidence of the Biden Administration’s “whole of government” approach to limit what it views as anticompetitive patent procurement practices.1 It remains to be seen how the FDA and USPTO will actually work together to address these issues, and whether similar interagency efforts may influence or support aggressive reforms to current patent laws to effectively limit the identified patent procurement practices.


The patent system was established in the US Constitution “[t]o promote the Progress of Science and useful Arts.” US Const. Art. I, § 8. Patent rights are lawfully granted if the requirements of 35 U.S.C. §§101-103 and 112 are satisfied. In particular, the USPTO must determine that an invention is both novel and non-obvious prior to granting of a patent. As a member of the World Trade Organization (WTO), the United States also cannot discriminate between different fields of technology in its patent regime under TRIPS Article 27.1.

Traditionally, FDA only plays an administrative role when it comes to patents related to pharmaceutical products. For small molecule drugs, the Federal Food, Drug, and Cosmetic Act (FD&C Act) requires a new drug application (NDA) applicant to submit to FDA information on patents that claim the drug that is subject of an NDA or approved uses thereof. FDA maintains the “Orange Book” listing, inter alia, the patent numbers and expiration dates associated with each innovator drug based on the submitted information. For biologics, the Biological Product Patent Transparency (BPPT) section of the Consolidated Appropriations Act of 2021 added a Purple Book listing requirement, which requires FDA to publish patent lists in the Purple Book not later than 180 days after the date of enactment (June 25, 2021). The key difference between the Purple Book and the Orange Book requirements is that based on the language in 42 U.S.C. 262(k)(9)(iii), the biologics license application (BLA) holder (brand sponsor patent owner) is only required to submit a patent list to FDA when it engages in a “patent dance” with a biosimilar applicant, where parties exchange confidential information related to the biosimilar product.

Despite that purely administrative role in patent-related matters, FDA now raises concern with three particular types of patent procurement strategies: (i) patent thickets, (ii) patent evergreening, and (iii) product hopping.

Patent “Thickets”

In the Drug Pricing and Pharmaceutical Patenting Practices report authored by the Congressional Research Service (CRS Report),2 a patent thicket is defined as the practice of “filing numerous patents on the same product.” Nonetheless, in FDA’s letter to the USPTO, it narrowly construed this as the practice of filing continuation applications. FDA’s concern is that possession of many overlapping patents on a product discourages competitors from market entry due to the potential high risks and costs of litigation, despite the fact that continuation applications generally share the same expiry date as the parent application. However, continuation application filing practice is a lawfully allowed patent procurement practice under 35 U.S.C § 120. Additionally, no statute has been enacted to bar patent “thickets” and recent actions to challenge such conduct under the antitrust laws have been unsuccessful. Thus, under the current patent law, without statutory changes, the USPTO would have a very limited role in curtailing the continuation filing practice identified by FDA.

Patent “Evergreening”

The CRS Report defines patent “evergreening” as “the practice of filing for new patents on secondary features of a particular product as earlier patents expire, thereby extending patent exclusivity past the original twenty-year term” provided by an initial patent family.3 FDA’s letter expresses concern about such post‑approval patent procurement efforts covering aspects of previously approved products, including new formulations, new delivery systems, and new methods of use. The letter questions whether such practices truly encourage meaningful innovations.

As discussed above, prior to granting any patents, the USPTO must determine that an invention is useful, novel, and non-obvious, among other requirements codified in the US Code. Bound by these requirements, the USPTO does not grant patents to inventions that it deems obvious and lacking utility. In other words, as long as an innovation meets the patentable requirements including novelty and non-obviousness, the USPTO must continue to grant patent rights to such an innovation, regardless of whether that invention occurred before or after the original FDA approval.

Furthermore, under current patent law, there already exists a judicially created doctrine known as non‑statutory obviousness-type double patenting (OTDP), which prevents improper term extension of patent rights through filings of patentably indistinct claims. The USPTO regularly applies this doctrine during patent prosecution to reject applications claiming obvious variations of issued claims owned by the same entity. Filing of a Terminal Disclaimer obviates OTDP rejections, but reduces the term of the second patent such that it cannot extend beyond the term of the earlier expiring patent. The result is that a patent owner cannot effectively extend the term of an initial patent by a later-filed application if the later-filed claims do not embody meaningful, non-obvious innovations.

In sum, despite the concerns expressed in Acting Commissioner Woodcock’s letter, patent law already provides certain guardrails against improper patent evergreening, all of which are exercised by the USPTO during the patent examination process.

“Product Hopping”

“Product hopping” is used by FDA to refer to the practice where a brand company seeks to preserve its market position by inducing customers to transition to a new product, or new version of a product, that is protected by a longer-term patent. This can include submitting a new NDA or BLA for a modified version of a previously approved product when the exclusivity of the original product is about to expire. FDA’s concern is that the new product may be protected by newly acquired patents, thus delaying generic or biosimilar competitors. Often, many in the patient population have switched from the original product formulation in order to take advantage of the purported benefits of the new product.

As discussed in the above patent “evergreening” section, if an invention meets all of the codified patentable requirements including novelty and non-obviousness, it deserves to be granted patent protection by the USPTO. Whether the resulting patent covers a modified version of a previously approved pharmaceutical product is not a condition for patentability under current patent law. Thus, addressing the issue of product hopping is beyond the purview of the USPTO, and would require changes to current patent laws.

Historical and Other Recent Efforts by the Federal Trade Commission to Curtail Patent Misuse

Despite limitations on the USPTO’s ability to address allegedly anticompetitive patent activity, this is an area where the US Federal Trade Commission (FTC) has been extremely active in recent years. Notably, in the pharmaceutical industry, the FTC has challenged patent litigation settlements between brand companies and generic companies that allegedly delayed the entry of generic competition. Those challenges ultimately led to the US Supreme Court’s 2013 decision in FTC v. Actavis, which rejected the “scope of the patent” test and allowed antitrust review of such settlements. The FTC (as well as state Attorneys General) also have challenged several instances of alleged “product hopping.” Most recently, the FTC authorized an omnibus compulsory process resolution to investigate alleged abuses of intellectual property.4 According to the FTC, “[c]onduct involving abuse of intellectual property rights has been a source of much anticompetitive and deceptive conduct in many different areas, including pharmaceuticals, technology and gasoline refining, and this omnibus [resolution] will allow staff to expeditiously investigate allegations in this area.” More generally, the EO directs the Secretary of Health and Human Services to work with the FTC to identify and address “any efforts to impede generic drug and biosimilar competition”.

Recent Congressional Efforts

The topic of the interplay between drug pricing and pharmaceutical patents has been a subject of a number of recent Congressional Research Service reports.5 On April 28, 2021, Senators John Cornyn [R-TX] and Richard Blumenthal [D-CT] introduced S.1435 Affordable Prescriptions for Patients Act of 2021. This bipartisan bill proposes to amend the Federal Trade Commission Act by prohibiting “product hopping”, and 35 USC 271(e) to limit the number of secondary patents that can be asserted by a brand company on a biosimilar applicant, limiting the effects of allegedly improper patent “thicket” and patent “evergreening” activities. This bill was advanced by the Senate Judiciary Committee unanimously on July 29, 2021.

A similar bill was also introduced in the House on April 4, 2021, H.R.2873 Affordable Prescription for Patients Through Promoting Competition Act of 2021, which only addresses the amendments to the Federal Trade Commission Act without amending the patent statute.

These bills, if enacted into law, would focus on curtailing the negative effects of “patent thicket”, “patent evergreening”, and “product hopping” at the patent enforcement stage, avoiding the need for changing the patentability standards of pharmaceutical patents.

It is also worth noting that just one day prior to the FDA letter, Senators Patrick Leahy [D-VT] and Thom Tillis [R-NC], separately sent a letter to the USPTO raising concerns of inappropriate patent prosecution practices related to pharmaceutical patents. Specifically, Senators Leahy and Tillis are concerned that some patent applicants may make statements during patent prosecutions that are inconsistent with statements made to other federal agencies such as the FDA. This letter requests the USPTO to take steps to require applicants to disclose statements made to other agencies during the patent prosecution process. However, current patent regulations already set forth a duty for patent applicants and practitioners to disclose information material to patentability. See 37 CFR 1.56. Information that refutes or is inconsistent with a position that an applicant takes in asserting an argument of patentability is currently considered as information material to patentability, and should be submitted to the USPTO under the current patent regulations. Nonetheless, if USPTO sees the need to specify such information in its patent regulations, it may do so through rule changes processes.

Implications of the FDA Letter

Without legislative reform, the USPTO must continue to abide to existing patent statutes in determining whether pharmaceutical inventions would be patentable. However, the current political atmosphere may cause the USPTO to take a closer look at certain pharmaceutical patent cases where it has more subjective discretion. The USPTO may also choose to propose new rules and regulation to impose additional disclosure requirements on patent applicants, if it deems necessary. Even if the USPTO does not have the specific power to combat the alleged patent abuses raised by the FDA’s letter, the FTC is likely to continue to focus on these issues in its competition enforcement efforts.

The specific proposals in the FDA letter focus on providing support to USPTO’s operations, and do not directly impose additional actions from patent applicants. The FDA’s offer to provide training sessions to patent examiners on pharmaceutical related issues could ensure that examiners in the relevant technology centers are on equal footing with each other when examining pharmaceutical patent cases. The FDA’s suggestion that examiners have additional examination time for pharmaceutical patent applications, if implemented by the USPTO, could allow for increased scrutiny. Regardless, examiner interviews would continue to be a valuable tool for pharmaceutical patent applicants to address various issues and rejections raised by examiners during prosecution. Applicants should also continue to carefully consider the impact of obviousness-type double patenting on its patent portfolio.

Finally, legislative reform placing various limitations on enforcing a large number of patents in pharmaceutical cases could reduce the alleged impact of “patent thickets,” “patent evergreening” and “product hopping”—but at a great risk of mistakes that could disturb legitimate pharmaceutical innovation, to the detriment of patients.

© Arnold & Porter Kaye Scholer LLP 2021 All Rights Reserved. This Advisory is intended to be a general summary of the law and does not constitute legal advice. You should consult with counsel to determine applicable legal requirements in a specific fact situation.

  1. The Executive Order further encouraged the Attorney General and the Secretary of Commerce to consider “whether to revise their position on the intersection of the intellectual property and antitrust laws”, and directed the Secretary of Agriculture to work with the USPTO to submit a report to discuss concerns with the intellectual property system reducing competition in seed and other input markets and strategies for addressing those concerns.

  2. Congressional Research Service, “Drug Pricing and Pharmaceutical Patenting Practices,” (Feb. 11, 2020).

  3. CRS Report

  4. The omnibus compulsory process resolution enables the FTC to issue civil investigative demands and subpoenas for documents and testimony these investigations for a period of 10 years.

  5. See, e.g., Congressional Research Service, “Drug Prices: The Role of Patents and Regulatory Exclusivities” (Feb. 10, 2021); Congressional Research Service, “Drug Pricing and Pharmaceutical Patenting Practices” (Feb. 11, 2020); Congressional Research Service, “Drug Pricing and the Law: Pharmaceutical Patent Disputes”; Congressional Research Service, “Drug Pricing and Intellectual Property Law:  A Legal Overview for the 116th Congress” (April 4, 2019).