API certification is voluntary.
It's certification and listing on API list is not required when oil manufacturers are not displaying related API logos on the labels .......
which is typical in Euro specs oils.
Hence, I would say this Total Quartz Racing 10W50 IS an API SN as claimed.
Note that no API logos is displayed on its labels , thus not on API listings.
Voluntary yes but licensed nevertheless.
So I can claim my oil is API SN in a PDS without being licensed? Just as long as I don't print it on the label as well.