A bill to amend the Endangered Species Act of 1973 to make it more consistent with the Marine Mammal Protection Act of 1972.

Allows the Secretary of Commerce to grant exemption, under such terms as he may prescribe, to the Endangered Species Act to allow possession and sale of bones and teeth of marine mammals of the order cetacea, which were lawfully held within the United States on December 21, 1972.

Provides that in actions brought for specified violations of the Endangered Species Act there shall be a rebuttable presumption that such exemption does not apply, and that any person claiming the benefit of such exemption shall have the burden of overcoming the presumption. (Amends 16 U.S.C. 1539)