If "1-DECENE, TETRAMER AND TRIMER HYDROGENATED" is standard PAO, then I suspect that many M1 products have Group V Ester base stock that is not disclosed in the Korean MSDS.
For example here is the breakdown of major components for various Mobil 1 products in Korea (1% or less is omitted):
M1 0W-40:
1-DECENE, TETRAMER AND TRIMER HYDROGENATED 68649-12-7 10 - 20%
POLYOLEFIN POLYAMINE SUCCINIMIDE 147880-09-9 1 - 5%
Trade Secret 01 Trade Secret 40-50%
Trade Secret 02 Trade Secret 10-20%
M1 0W-30 Advanced Fuel Economy:
1-DECENE, TETRAMER AND TRIMER HYDROGENATED 68649-12-7 50 - 60%
POLYOLEFIN POLYAMINE SUCCINIMIDE 147880-09-9 1 - 5%
Trade Secret 01 Trade Secret 1-5%
Trade Secret 02 Trade Secret 1-5%
Trade Secret 03 Trade Secret 10-20%
Trade Secret 04 Trade Secret 1-5%
Trade Secret 05 Trade Secret 1-5%
Mobil 1 0W-30 (probably European Formula):
1-DECENE, TETRAMER AND TRIMER HYDROGENATED 68649-12-7 70 - 80%
POLYOLEFIN POLYAMINE SUCCINIMIDE 147880-09-9 1 - 5%
Trade Secret 01 Trade Secret 5-10%
Trade Secret 02 Trade Secret 5-10%
Trade Secret 03 Trade Secret 1-5%
Trade Secret 04 Trade Secret 1-5%
Trade Secret 05 Trade Secret 1-5%
Mobil 1 5W-30:
1-DECENE, TETRAMER AND TRIMER HYDROGENATED 68649-12-7 30 - 40%
POLYOLEFIN POLYAMINE SUCCINIMIDE 147880-09-9 1 - 5%
Base Oil 1 72623-87-1 30-40%
Trade Secret 01 Trade Secret 5-10%
Trade Secret 02 Trade Secret 5-10%
Trade Secret 03 Trade Secret 1-5%
Trade Secret 04 Trade Secret 1-5%
Trade Secret 05 Trade Secret 1-5%
Mobil 1 5W-50:
1-DECENE, TETRAMER AND TRIMER HYDROGENATED 68649-12-7 50 - 60%
POLYOLEFIN POLYAMINE SUCCINIMIDE 147880-09-9 1 - 5%
Trade Secret 01 Trade Secret 5-10%
Trade Secret 02 Trade Secret 10-20%
Trade Secret 04 Trade Secret 1-5%
Trade Secret 05 Trade Secret 40-50%
Trade Secret 07 Trade Secret 1-5%