The Legal-Entity in a Potential-Sale that may become theSale-Vendor in a possible future Sale
(<=> (Vendor ?X)
(Or (Exists (?Sale) (Sale-Vendor ?Sale ?X))
(Exists (?For-Sale) (For-Sale-Vendor ?For-Sale ?X))
(Exists (?Potential-Sale)
(Potential-Vendor ?Potential-Sale ?X))))