This guidance is intended to address anticipated questions regarding product identifiers that are required under section 582 of the Federal Food, Drug, and Cosmetic Act (FD&C Act) (21 U.S.C. 360eee-1), as added by the Drug Supply Chain Security Act (DSCSA) (Title II of Public Law 113-54), for packages and homogenous cases of certain drug products. , , , Section 582(b)(2) and (e)(2) require manufacturers and repackagers, respectively, to affix or imprint a product identifier to each package and homogenous case of a product intended to be introduced in a transaction in(to) commerce beginning November 27, 2017, and November 27, 2018, respectively. This guidance is intended to clarify FDA’s interpretation of both these requirements, including as they relate to the linear barcode requirements under 21 CFR 201.25.