Does MarAd have to plead that "buyer" status is an affirmative defense in a security agreement?

MarAd cites no authority in support of this position, and we are loath to establish an exception premised upon language which is probably common to security agreements of this type. The facts concerning a purchaser's status, furthermore, are in most cases more easily accessible to the purchaser, a consideration which favors a requirement that "buyer" status be pleaded as an affirmative defense. See Gomez v. Toledo, 446 U.S. at 640-41, 100 S.Ct. at 1923-24.