FTC Issues a Third Round of Warning Letters Over Improper Orange Book Listings

June 30, 2025

Authored by: Gina Lee

On May 21, 2025, the Federal Trade Commission (FTC) renewed its efforts to challenge pharmaceutical manufacturers that have allegedly listed patents improperly in the Food and Drug Administration’s (FDA) publication of “Approved Drug Products with Therapeutics Equivalence Evaluations,” also known as the Orange Book.¹ The Orange Book is the FDA’s official publication identifying drugs that have been approved and providing information related to patents and exclusivity.² FTC’s May 2025 letter is its third letter since 2023 urging sponsors to delist certain challenged patents, and it comes on the heels of the Federal Circuit’s much-anticipated decision in Teva Branded Pharm. Prods. R&D, Inc. v. Amneal Pharms. of N.Y., LLC, 124 F.4th 898 (Fed. Cir. 2024).³ While the Federal Circuit decision certainly added significantly to the longstanding debate about listability, hard work remains in applying it (assuming the Supreme Court does not grant certiorari).

On September 14, 2023, the FTC issued a policy statement announcing that “[l]isting patents in the Orange Book that do not meet the statutory listing criteria may constitute an unfair method of competition in violation of Section 5 of the Federal Trade Commission Act.”⁴ If a generic company chooses to challenge a listed patent, the brand manufacturer can bring a patent infringement suit and a 30-month stay may arise, where the FDA is prohibited from approving the generic.⁵ The FTC asserted that improperly listing patents may delay generic alternatives from entering the market and could block competition.⁶ This practice ultimately may lead to artificially high drug prices and limited patient access to lower-cost medications.⁷ In the policy statement, the FTC stated that certain submitted patents in the Orange Book “claim neither the reference listed drug nor a method of using it,” which the FTC asserted are improperly listed patents.⁸ The purpose of the policy statement was to put manufacturers on notice that the FTC intended to evaluate patents listed in the Orange Book and determine whether they constitute anti-competitive behavior.⁹

In the wake of the policy statement, the FTC issued a first round of warning letters on November 7, 2023 to ten pharmaceutical manufacturers, which challenged more than 100 allegedly improper patent listings.¹⁰ In the first round of letters, the FTC focused on patents that related to brand-name asthma inhalers, epinephrine autoinjectors, and an ophthalmic drop.¹¹ These companies were given “30 days to withdraw or amend these listings, or certify under penalty of perjury that the listings comply with applicable statutory and regulatory requirements.”¹² The FTC later announced that the first round of letters successfully resulted in the delisting of patents by Kaleo, Impax Labs, GlaxoSmithKline, and Glaxo Group.¹³ Additionally, AstraZeneca, Boehringer Ingelheim, and GlaxoSmithKline committed to capping the out-of-pocket cost for theirs inhalers at $35.¹⁴

On April 30, 2024, the FTC issued a second wave of warning letters.¹⁵ This time, the FTC expanded its targets to include improperly listed patents related to medications for weight loss, diabetes, asthma and chronic obstructive pulmonary disease (COPD).¹⁶ Subsequent to the second round of warning letters, it appears that several of the targeted manufacturers delisted their challenged patents; however, seven companies did not heed to the FTC’s warnings and continued to list their alleged improper patents in the Orange Book.

In December 2024, the Federal Circuit clarified the standard for qualifying listed patents in Teva Branded Pharm. Prods. R&D, Inc. v. Amneal Pharms. of N.Y., LLC, holding that “[t]o list a patent in the Orange Book, that patent . . . claim that drug for which the applicant submitted the application and for which the application was approved. And to claim that drug, the patent must claim at least the active ingredient. Thus, patents claiming just the device components of the product approved in an NDA do not meet the listing requirement . . . .”¹⁷ About claiming, the Federal Circuit elaborated that “a patent claims the drug when it particularly points out and distinctly claims the drug as the invention.”¹⁸

With the Federal Circuit decision in hand, the FTC issued its third round of warning letters on May 21, 2025 to Covis, Amphastar, Novartis, Mylan, and three subsidiaries of Teva.¹⁹ These recent warning letters did not challenge any new patents, but targeted those previously challenged by the FTC in the first two warning letters, but still remain in the Orange Book.²⁰ These companies were, again, given the option to either “withdraw or amend the listing or certify under penalty that the listing complies with applicable statutory and regulatory requirements” within 30 days from receipt of the letter.²¹ In response, Covis and Amphastar have since asked the FDA to delist their disputed patents, while the remainder have not responded by the June 20th deadline.²²

Companies should proactively review their patents to ensure that they satisfy the Orange Book listing requirements and scrutinize planned submissions carefully well before a New Drug Application is filed. While the Federal Circuit provided important guidance and clarification of the patent listing provisions of the Hatch-Waxman Amendments, the hard work of applying this guidance remains. For example, stakeholders will likely grapple with whether patent claims “particularly point out and distinctly claims the drug” in some instances where the active ingredient is not expressly recited as a species.²³ It should also be noted that the final word in Teva has not been decisively cast—the Supreme Court granted an extension for the deadline to file a petition for a writ of certiorari until July 31, 2025.