Nero? Countermark SPQR
ID: 0083
It has been suggested this is a SPQR counter mark. This is still unconfirmed but the best view so far.
From vcoins:
The ‘SPQR’ countermark and its derivatives, (QR, PR, SPR, etc) are only found on later-reign AEs coinage of Nero from Lugdunum; these countermarks were applied by Gallic rebels circa 68 AD, under the command of rebel governor Gaius Julius Vindex, governor of Gallia Lugdunensis (of which Lugdunum was the capital city). Vindex swore allegiance to would-be emperor Servius Sulpicius Galba, although he was defeated in a battle against loyalist legions stationed in Germania before he could join up with Galba’s forces. Galba, of course, fared little better. Interestingly, all of these civil war countermarks appear in the same location, directly across Nero’s neck.