As there is no Royal Purple lubricant that is certified by GM, there is no RP lubricant that is recommended by GM.
I'm not saying that RP wouldn't pay the claim - but there is a definite clause in their policy that would easily allow them to.
You have made an arguable point. However, you only bolded "recommended by the OEM" when the phrase in its context reads "Royal Purple
lubricant type recommended by the OEM."
The language does not require that a lubricant be a specific lubricant formulation recommended by an OEM, which would be quite silly since OEMs do not (to my knowledge) recommend RP.
In our case, the OEM has recommended a "lubricant type," such type being "engine oil licensed to the dexos1 specfication,
or equivalent, of the proper SAE viscosity grade [5w-30]."
It would be a pretty tough sell for Royal Purple to claim that their oil exceeds dexos specs (the type recommended by the OEM) and then turn around and then deny warranty coverage on the ground that their oil is not the "lubricant type recommended by the OEM." This is, of course, assuming that the oil in question is correct "SAE viscosity grade" recommended by the OEM.
Again, you have an arguable point based on the ambiguous language used by RP in their policy. In the end, however, I believe that such ambiguity should be resolved against RP and likely would be if it ever came down to it. See
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