TomboyX, PBC

WARNING LETTER TomboyX, PBC MARCS-CMS 720849 — December 16, 2025 More Warning Letters Warning Letters About Warning and Close-Out Letters Delivery Method: VIA Electronic Mail Product: Medical Devices Recipient: Recipient Name Fran Dunaway Recipient Title President TomboyX, PBC 2200 Western Avenue Seattle , WA 98121 United States legal@tomboyx.com Issuing Office: Center for Devices and Radiological Health United States WARNING LETTER CMS #720849 December 16, 2025 Dear Fran Dunaway: The United States Food and Drug Administration (FDA) has reviewed TomboyX, PBC’s (“your firm”) website (tomboyx.com) and observed that your website offers various breast binders for sale. Under section 201(h) of the Federal Food, Drug, and Cosmetic Act (the Act), 21 U.S.C. § 321(h), these products are devices because they are intended for use in the diagnosis of disease or other conditions or in the cure, mitigation, treatment, or prevention of disease, or to affect the structure or any function of the body. Our review of your firm’s website revealed statements that these breast binders (example trade names: “Compression Top - Black”, “Racerback Compression Top - Chai”, “V Neck Compression Top - White”) are intended for use in the diagnosis of disease or other conditions, or in the cure, mitigation, treatment, or prevention of disease, or intended to affect the structure or any function of the body, including: Per your firm’s website: “Many individuals who identify as transgender, non-binary, or gender-fluid utilize chest binding as a way to help manage their own dysphoria” Our review also revealed statements that you manufacture these devices within the meaning of section 510 of the Act (21 U.S.C. § 360) (e.g., “We pay obsessive attention to every design aspect, leaving no detail overlooked so that our community can live and experience a life unbound.”). Under section 510 of the Act (21 U.S.C. § 360), manufacturers of medical devices are required to annually register with the FDA. In September 2007, section 510 of the Act was amended by the Food and Drug Administration Amendments Act of 2007 (Pub. L. 110-85) to require domestic and foreign device establishments to submit their annual establishment registration and device listing information to FDA by electronic means [section 510(p) of the Act (21 U.S.C. § 360(p))] during the period beginning October 1st and ending December 31st of each year. Our records indicate that you have not registered or listed these devices for fiscal year 2026. Therefore the devices are misbranded within the meaning of section 502(o) of the Act (21 U.S.C. § 352(0)), in that they were manufactured, prepared, propagated, compounded, or processed in an establishment not duly registered under section 510 of the Act (21 U.S.C. § 360) and were not included in a list required by section 510(j) of the Act (21 U.S.C. § 360(j)). Your firm should take prompt action to address any violations identified in this letter. Failure to adequately address this matter may result in regulatory action being initiated by the FDA without further notice. These actions include, but are not limited to, seizure and injunction. Other federal agencies may take your compliance with the FD&C Act and its implementing regulations into account when considering the award of federal contracts. Please notify this office in writing within fifteen business days from the date you receive this letter of the specific steps your firm has taken to address the noted violations, as well as an explanation of how your firm plans to prevent these violations, or similar violations, from occurring again. Include documentation of the corrections and/or corrective actions (which must address systemic problems) that your firm has taken. If your firm’s planned corrections and/or corrective actions will occur over time, please include a timetable for implementation of those activities. If corrections and/or corrective actions cannot be completed within fifteen business days, state the reason for the delay and the time within which these activities will be completed. Your firm’s response should be comprehensive and address any violations included in this Warning Letter. If you believe that your products are not in violation of the FD&C Act, include your reasoning and any supporting information for our consideration as part of your response. Your firm’s response should be sent via email to CDRHEnforcement@fda.hhs.gov. Please include in the subject line, “CMS 720849” when replying. Finally, you should know that this letter is not intended to be an all-inclusive list of the violations at your firm’s facility. It is your firm’s responsibility to ensure compliance with applicable laws and regulations administered by FDA. Your firm should investigate and determine the causes of any violations and take prompt actions to address any violations and bring the products into compliance. Sincerely yours, /S/ Michael J. Hoffmann Director Office of Health Technology 3 - Gastrorenal, ObGyn, General Hospital, and Urology Devices Office of Product Evaluation and Quality Center for Devices and Radiological Health Food and Drug Administration Content current as of: 12/18/2025 Regulated Product(s) Medical Devices