A bill to amend the Merchant Marine Act, 1936, to promote the series construction of U.S.-flag merchant vessels.

Amends the Merchant Marine Act, 1936, to direct the Secretary of Commerce to reduce by five percent the construction differential subsidy for the construction of a vessel if (1) the type of vessel to be constructed is not a standard vessel and is not an innovative type likely to become a standard vessel and (2) a standard vessel could substantially serve the purpose for which the vessel is intended to be used.