Registration of a mark on the supplemental register, or under the Act of March 19, 1920, shall not preclude registration by the registrant on the principal register established by this chapter. Registration of a mark on the supplemental register shall not constitute an admission that the mark has not acquired distinctiveness.

(July 5, 1946, ch. 540, title II, §27, 60 Stat. 436; Pub. L. 100–667, title I, §124, Nov. 16, 1988, 102 Stat. 3943.)