Still can not find a product data sheet for the Defy SN version.
I just bought a jug of the 10-30 SN version. Good price compared to everything else sold as a high mileage oil. My best guess is that SOPUS is selling the SN version now to compete with Mobil Super 5K high mileage, Havoline high mileage, and the Castrol high mileage. All those oils are SN rated and resource conserving too.