https://rpc.ashmus.ox.ac.uk/countermark/368 

GIC 245

Athena standing r., holding with spear in r. hand and shield with l. (on obverse)

rectangular 

6 x 4.5 mm 

Antioch (Syria)

The connection of Minerva with Domitian suggests that this is an imperial cmk, There can be little doubt that it was applied between AD 83 and AD 96. It did not have a denominational significance as it was applied to both denominations of the S C series. It is noticeable that it only rarely occurs on the same coins as legionary cmk's (472 and 726), probably for the reason that the legionary countermarks were not applied in the area of Antioch.