21 CFR § 201.2
Drugs and devices; National Drug Code numbers
June 25, 2020
The National Drug Code (NDC) number is requested but not required to appear on all drug labels and in all drug labeling, including the label of any prescription drug container furnished to a consumer.
[40 FR 52002, Nov. 7, 1975, as amended at 81 FR 60212, Aug. 31, 2016]