I have the INT version but I do not see this Pset.
I think it was created in this Dialog. This can be seen from the fact that it has a red X before its name. If you click the red X, the Pset_Spec set will be deleted. IFC Properties can be deleted only if they were user created, default IFC Properties cannot be deleted in any way, as far as I know.
So if you don't need it I think it is safe for you to just delete it.
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