When an aircraft that is registered in the United States is sold, the holder of the Certificate of Aircraft Registration must remove, before its delivery to the purchaser, all United States marks from the aircraft, unless the purchaser is—

(a) A citizen of the United States;

(b) An individual citizen of a foreign country who is lawfully admitted for permanent residence in the United States; or

(c) When the aircraft is to be based and primarily used in the United States, a corporation (other than a corporation which is a citizen of the United States) lawfully organized and doing business under the laws of the United States or any State thereof.