California Code, Health and Safety Code - HSC § 114039

(a) Raw shucked shellfish shall be obtained in nonreturnable packages that bear a legible label that identifies the name, address, and certification number of the shucker-packer or repacker of the molluscan shellfish, and a “sell by” date or a “best if used by” date for packages with a capacity of less than one-half gallon, or the date shucked for packages with a capacity of one-half gallon or more.

(b) A package of raw shucked shellfish that does not bear a label or that bears a label that does not contain all the information required by subdivision (a) shall be subject to impound pursuant toSection 114393.