"Art dealer" means a person who is in the business of dealing exclusively or nonexclusively in fine art multiples, a person who by his occupation holds himself out as having knowledge or skill peculiar to fine art multiples or persons to whom that knowledge or [...]

(1) "Art dealer" means a person engaged in the business of selling works of art, other than a person exclusively engaged in the business of selling goods at public auction, and other than a nonprofit organization.