When Athens introduced its New Style coinage, the mint didn't just redesign the owl, it turned the reverse into a miniature public record. Packed around the owl-on-amphora design, collectors will typically find the names of two principal magistrates along with the name of a third. The first and second magistrates served for the entire minting year, which ran roughly parallel to the Athenian civil calendar from midsummer to midsummer. These are the names that define an "issue", such as Timarchos and Nikagoras on this particular piece. During the earliest years of the series, only these two names (or their monograms) appear, and they typically occupy the most prominent positions flanking the owl.

The third magistrate, however, is the truly fascinating one. His name changes frequently throughout the year, and because these changes track with the dating, the standard interpretation is that this was a monthly office. Over the course of a full year, up to a dozen or so different third names can appear alongside the same senior pair. This official seems to have been the man immediately responsible for that month's production, a kind of rotating quality-control officer whose name personally guaranteed the batch.