Since the late 380s all the bronze coins struck by Western mints were of the smallest AE4 denomination. Starting from 404, the mint of Rome resumed the issuing of AE3 coins, characterised by the presence of the S M mark (Sacra Moneta) associated with the mint mark. The S M mark always appears in subsequent issues of the mint of Rome until 417-418, after which it is no longer found in Western coins.
This paper aims to connect this mark to the presence of the emperor or members of his comitatus in the place of issue. The S M mark would have been used to highlight not only the context of issue but also its function: the coins would have been minted according to the needs or purposes of the comitatus, perhaps to supply the arca vinaria or, in connection with adventus ceremonies, for distribution to the people as congiaria.