From Thasos - Amphora Stamps

: These typically featured two names—the official and the producer—accompanied by a decorative device.

Thasian amphora stamps are a unique class of archaeological artifacts that served as an early regulatory system for the wine trade. Starting in the early 4th century B.C. and lasting for over 250 years, the island of Thasos implemented a complex stamping practice on ceramic transport containers. The Purpose of Thasian Stamps Amphora stamps from Thasos

: The stamps often included the ethnicon "Θασίων" (of the Thasians) to denote the origin. Archaeological Significance (PDF) Deciphering Greek Amphora Stamps - ResearchGate : These typically featured two names—the official and