Catalog numbers are crucial for identification. The pattern “ATVR-###” likely follows Attackers’ VR series naming convention. “AT” stands for Attackers, “VR” for the format, and “017” means it is the 17th release in that specific VR line. This number helps distributors, retailers, and collectors avoid confusion with non-VR titles like ADN or SHKD series.
Possessing a self-ripped copy of a purchased VR video for personal backup may fall under fair use in some jurisdictions, but sharing the “UPD” file publicly is infringement.