On July 15, 2025, U.S. Senators Peter Welch (D‑VT), Josh Hawley (R‑MO), and Amy Klobuchar (D‑MN) introduced the ETHIC Act—the Eliminating Thickets to Increase Competition Act (S. 2276)—in the U.S. Senate.[1] The bill is designed to limit the number of drug patents that may be asserted by patent holders (often branded drug companies) in patent infringement actions, with the goal of increasing competition and lowering drug prices by easing the ability for generic and biosimilar drug makers to enter the market.
What Is the ETHIC Act?
The proposed bill seeks to add an amendment to 35 U.S.C. § 271(e)—the statute in play in Hatch-Waxman and biosimilar patent litigation cases—that makes it an “artificial act of infringement” to file a generic drug application (i.e., ANDA or 505(b)(2)) or biosimilar drug application (i.e., aBLA) with the FDA on a drug claimed in a patent. The bill would only apply to patents asserted against generic and biosimilar drug companies, and thus would not impact other industries.
The proposed bill states:
A person who brings an action for infringement of a patent under [35 U.S.C. § 271(e)] against a party described in subparagraph (B) [e.g. a generic or biosimilar drug applicant] may assert in the action not more than one patent per Patent Group.”[2]
The bill was read twice and referred to the Committee on the Judiciary.[3] A related identical bill was previously introduced into the House of Representatives on May 8, 2025, also read twice, and referred to the House Committee on the Judiciary.[4]
What Are Patent Thickets?
A “patent thicket” is the term generally applied to groups of overlapping patents that cover a single product. The various patent claims in a thicket may cover different aspects of the product, or they may target the same aspect of the product with similar but non-identical claims. Often, a single drug may be protected by two, three, or even dozens of patents covering a drug molecule, drug formulation, manufacturing process, or drug delivery methods. Such “patent thickets” can sometimes be used to extend patent exclusivity well beyond the original patent’s expiration, which can block and delay generic drugs and biosimilars from entering the market. Further, “patent thickets” can increase the complexity and cost of pharmaceutical patent litigation, as NDA and BLA drug holders (i.e., branded drug companies) often assert infringement or several (or even dozens) of patents against generic and biosimilar drug applicants.
As defined in the proposed ETHIC act, a “Patent Group” means two or more commonly-owned patents or applications that are related by way of terminal disclaimers under 35 U.S.C. § 253.[5] Each patent or application that is identified on, or is subject to, a terminal disclaimer for a commonly-owned patent is part of the same “Patent Group.” Terminal disclaimers typically are filed by applicants during patent prosecution to overcome obviousness-type double patenting (OTDP) rejections made by the USPTO.
Why it Matters.
If the bill passes, branded drug companies would be limited to asserting infringement of just one patent in a terminally disclaimed Patent Group against a given defendant. This would mean that, if the asserted patent in a Patent Group is invalidated or found not infringed by a court, the patentee could not assert a new or different patent from the same Patent Group against that defendant. This could potentially pave the way for quicker and cheaper access for generic and biosimilar drug companies to launch their products on the market.
Branded and generic drug companies should keep an eye on the bill’s progress. If passed, it could have significant impacts on patent litigators’ strategies and decision making before a complaint is filed in deciding which patent is “strongest” to assert. The bill also gives attorneys prosecuting patents directed to pharmaceutical and biotech inventions another reason to carefully consider whether to file a terminal disclaimer to overcome an OTDP rejection. As the ETHIC act is currently drafted, patent prosecutors could avoid potentially creating a “Patent Group” by making non-obviousness arguments over commonly owned patents rather than taking the more expeditious route of filing a terminal disclaimer.
[1] S. 2276- ETHIC Act (119th Congress, 1st session, Introduced Jul. 15, 2015), available at https://www.congress.gov/bill/119th-congress/senate-bill/2276/text
[2] Id.
[3] Id.
[4] H.R. 3269- ETHIC ACT (119th Congress, 1st session, Introduced May 8, 2025), available at https://www.congress.gov/bill/119th-congress/house-bill/3269/text
[5] See supra n.1.
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