Knobbe Martens
Jul 1, 2024

Branded Manufacturers Decline to Remove Patents From the Orange Book After Receiving Letters From the FTC

Written byAshley C. Morales & Michael L. Fuller

On Friday, June 21, 2024, the FDA updated its Patent Listing Dispute List to indicate that the ten pharmaceutical companies who had received warning letters from the FTC in April did not make changes to their patent listings in the FDA’s catalog in view of the warning letters.[1]

The warning letters sent to the pharmaceutical companies are part of the FTC’s new policy regarding listing of patents in the FDA’s “Approved Drug Products with Therapeutic Equivalence Evaluations” catalog, commonly known as the “Orange Book.”[2]  The Orange Book lists prescription and non-prescription drug products approved under Section 505 of the Federal Food, Drug, and Cosmetic Act, and is designed to put generic companies on notice of patents that a brand company claims cover a branded product.[3]

In September 2023, the FTC issued a new policy statement, supported by the FDA, stating that companies improperly listing patents in the Orange Book could face legal action.[4]  The FTC explained that listing patents in the Orange Book which do not meet the statutory listing criteria may constitute an unfair method of competition in violation of Section 5 of the FTC Act.[5] The FTC also stated that under this new policy, it may dispute patent listings through an FDA process that allows any interested person to request correction of patent information in the Orange Book.[6] The FTC identified a few additional means of enforcing its new policy, including considering a company’s history of improperly listing patents during merger review, and potentially referring cases to the Department of Justice in the event of false certifications made to support an improper Orange Book patent listing.[7]

As part of this new policy, in November 2023, the FTC began sending letters to certain pharmaceutical companies, notifying them that the FTC believed that certain patents were improperly or inaccurately listed in the Orange Book, and stating that the FTC had asked the FDA to review whether the patents were listed properly.[8] The first set of FTC letters were sent to ten branded drug companies, and called into question more than 100 patents.[9]  Of the ten companies receiving letters, four elected to delist most or all of the patents.[10]

In late April 2024, the FTC sent another round of letters to ten companies, including AstraZeneca Novo Nordisk, Boehringer Ingelheim, Covis Pharma, Glaxo-Smith Kline, Novartis Pharmaceuticals Corp., Teva Pharmaceutical Industries Ltd., and Amphastar Pharmaceuticals Inc., disputing the accuracy or relevance of more than 300 patent listings for 20 brand name products, and providing notice to the FDA.[11] The identified patents cover a variety of brand name products, including drugs to treat obesity, type-2 diabetes, asthma, COPD, and severe hypoglycemia in type-1 diabetes.[12]

Upon receiving their notice of the FTC’s disputes, the FDA sent the dispute information to the branded drug manufactures.[13] The branded drug manufactures then had 30 days to withdraw or amend their Orange Book listings or otherwise certify that the listings complied with statutory and regulatory requirements.[14] On June 21, 2024, with the issuance of the FDA’s updated Patent Listing Dispute List, it became clear that these ten companies had chosen not to remove the identified patents from the Orange Book or otherwise made changes to their listings.[15]

In the wake of the FTC’s letters, and the decision of branded pharmaceutical manufactures regarding delisting or keeping patents in the Orange Book, there is a renewed interest from the industry to obtain more clarification from the FDA regarding which patents should and should not be listed in the Orange Book.  In 2022, the FDA agreed to create a multidisciplinary working group to evaluate whether additional clarity is needed regarding the types of patents which should be included in or removed from the Orange Book under current statutory requirements.[16] While, to date, the FDA has not issued any additional guidance, in January 2024, the FDA indicated its intent to update its guidance on the submission of patent information for listing in the Orange Book in 2024.[17] It remains to be seen how or if the FDA’s new guidance will affect the FTC’s policy regarding listing of patents in the Orange Book.

Editor: Brenden S. Gingrich, Ph.D.


[1] FDA “Patent Listings Dispute List,” available at, last visited on June 25, 2024.

[2] Federal Trade Commission, “FTC Expands Patent Listing Challenges, Targeting More than 300 Junk Listings for Diabetes, Weight Loss, Asthma and COPD Drugs,” available at, last visited on June 25, 2024.

[3] Federal Trade Commission, “Federal Trade Commission Statement Concerning Brand Drug Manufacturers’ Improper Listing of Patents in the Orange Book,” available at, last visited on June 25, 2024. 

[4] Id.

[5] Id. at 3.

[6] Id. at 6 (citing 21 C.F.R. 314.53(f)(1)).

[7] Id. at 5-6.

[8] FTC, “FTC Challenges More than 100 Patents as Improperly Listed in the FDA’s Orange Book,” available at, last visited on June 25, 2024.  

[9] Id.

[10] Law360, “GSK, Kaleo Scale Back Orange Book IP in FTC Campaign,” available at, last visited on June 25, 2024

[11]See fn. 2.

[12] Id.

[13] Id.

[14] Id.

[15] Id.

[16] FDA, “The Listing of Patent Information in the Orange Book,” at 25, available at, last visited on June 25, 2024. 

[17] FDA, “CDER Guidance Agenda New, Revised Draft and Immediately in Effect Guidances for Publication in Calendar Year 2024,” available at, last visited on June 25, 2024.