The additive packages change on occasion, and for some viscosities, Pennzoil Conventional and Quaker State Conventional and Formula Shell are indistinguishable based on VOA alone. As for the "Formula Shell" and "Shell Formula" busienss, they're the same thing. Shell even has that transposition in their data sheet database. That's probably the origin of it, since PQIA and others would check and want to get the name "right," despite that the manufacturer didn't even get it right.