Any Legal-Entity that participates in at least one of:
- the Actual-Customer relationship with respect to some Sale,
- the Potential-Customer relationship with respect to some Potential-Sale,
- the Specified-Potential-Customer Relationship with some Sale-Offer
(=> (Customer ?X) (Or (Exists (?Sale) (Actual-Customer ?Sale ?X)) (Exists (?Potential-Sale) (Potential-Customer ?Potential-Sale ?X)) (Exists (?Sale-Offer) (Specified-Potential-Customer ?Sale-Offer ?X))))
(<=> (Customer ?X) (And (Legal-Entity ?X) (Actor ?X) (Or (Exists (?Sale) (Actual-Customer ?Sale ?X)) (Exists (?Potential-Sale) (Potential-Customer ?Potential-Sale ?X)) (Exists (?Sale-Offer) (Specified-Potential-Customer ?Sale-Offer ?X)))))
(=> (Market-Need ?Need) (Exists (?Customer) (And (Customer ?Customer) (Has-Need ?Customer ?Need) (Not (Exists (?For-Sale ?Product ?Feature) (And (Product-For-Sale ?For-Sale ?Product) (Has-Feature ?Product ?Feature) (Satisfies-Need ?Feature ?Need))))))) (=> (Set-Of-Customers ?Customers) (Forall (?X) (=> (Member ?X ?Customers) (Customer ?X))))
(<=> (Set-Of-Customers ?Customers) (And (Eo-Set ?Customers) (Set ?Customers) (Forall (?X) (=> (Member ?X ?Customers) (Customer ?X)))))