Yes, they say that, but, by law any PAO in the basestock gives them claim to call it a PAO oil. In the Dyson VOA I had done, there was olefins in the oil, just not a full base of PAO. So legally Mobil can say they have a PAO oil, even though the amount of PAO may vary. I am not bashing Mobil, it is a very good oil (the 0w-40 meets so many requirements of manufactures) in certain situations. I have done some UOA's on Mobil 1 and found that the 0w-40 shears dow to a low 30 wt (9.5 cSt) pretty quickly. A 30 wt oil is usually around 9.3 to 12.5 cSt (@100C). A 40 wt will be between 12.5 and 16.3 cSt (@100C). These kinematic viscosity measurements are per SAE J300 viscosity classification.
And the Castrol issue is not actually a lawsuit, just a marketing truthfullness dispute. And since the Supreme Court ruled in their favor, any oil with a hydrocraked basestock can be labled as a full synthetic, which most on the shelf are.
Oh and back to Mobil 1, I think the more heavy duty the oils is ( 15w50 or the truck and suv 5w-40) seem to have more PAO in the basestock, as these oils are much more shear stable than the 5w-30, 0w-40 et cetera.
Sorry for the long post, but there seems to be many misconceptions about synthetic motor oils. And I in no way am bashing ANY brand of oil, any thing you buy off the shelf (in a close viscosity range) will work just fine, really. Run what works for you and lets you sleep at night, I do not want to sound like I am picking on Mobil 1, I have used (and continue to use) Mobil 1 in many vehicles, and it has always worked extremly well, and produced some nice UOA's.
And the Yamalube is fine too, just that for the price, there are many better alternatives out there that will offer better engine protection.