"The FDA does not issue any kind of certification to demonstrate a manufacturer is in compliance with the FDA’s requirements." - US Food and Drug Administration
https://www.fda.gov/medical-devices/personal-protective-equipment-infection-control/face-masks-and-surgical-masks-covid-19-manufacturing-purchasing-importing-and-donating-masks-during
Q: I would like to purchase masks for COVID-19. How do I know if they are counterfeit or fraudulent?
A: The FDA does not issue any kind of certification to demonstrate a manufacturer is in compliance with the FDA’s requirements.
The FDA does not have an exhaustive list of all counterfeit or fraudulent products. To report fraudulent COVID-19 products to the FDA, please email FDA-COVID-19-Fraudulent-Products@fda.hhs.gov.