21 U.S.C. § 678 — Non-Federal jurisdiction of federally regulated matters; prohibition of additional or different requirements for establishments with inspection services and as to marking, labeling, packaging, and ingredients; recordkeeping and related requirements; concurrent jurisdiction over distribution for human food purposes of adulterated or misbranded and imported articles; other matters

This section decides which rules a state, territory, or the District of Columbia may add on top of federal meat inspection law. A state cannot add requirements about the premises, facilities, or operations of any federally inspected plant. It cannot do this if the state's rules go beyond or differ from the federal ones. There is one exception. A state may still add its own recordkeeping requirements, as long as they stay consistent with the federal recordkeeping rules in section 642. A state also cannot add marking, labeling, packaging, or ingredient requirements for products made at a federally inspected plant, beyond what federal law already requires. But states keep some power. A state may act alongside the Secretary to stop the sale of adulterated or misbranded food meant for human consumption. This applies once that food has left the inspected plant. It also applies once an imported product has entered the United States. Finally, this chapter does not stop a state from setting other rules on matters not covered above. Any such state action must stay consistent with this chapter.

The source credit indicates that this section was not part of the original 1907 enactment but was added later. The underlying act traces to the Act of March 4, 1907, chapter 2907, but the specific provision codified here—section 408 of title IV—was added by Public Law 90-201, section 16, enacted December 15, 1967, and published at 81 Stat. 600. The record shows only this single enactment event; no subsequent amendments to the section are reflected in the source credit. Public Law 90-201 is commonly identified as the Wholesome Meat Act of 1967. This era of federal meat-inspection law is generally understood to reflect congressional concern that the original 1906–1907 meat inspection framework applied only to meat moving in interstate or foreign commerce, leaving meat slaughtered and sold entirely within a single state outside federal inspection requirements. Reports and public discussion in the 1960s highlighted that some intrastate slaughtering establishments operated with inspection standards that were inconsistent or absent, raising food-safety concerns. The Wholesome Meat Act is commonly described as responding to this gap by requiring states to maintain meat-inspection programs "at least equal to" federal standards or else become subject to federal inspection, while also addressing how state and federal authority would coexist. Provisions concerning the division of regulatory authority between federal and state governments, such as the one presented here, are consistent with that broader purpose of coordinating overlapping jurisdiction. However, the record does not itself document the specific legislative reasoning behind this particular section's language, and no further detail should be inferred beyond this general historical understanding.