In carrying out transactions authorized by section 521 of this title, the Secretary of the Army and the Secretary of the Navy are authorized, in their discretion and provided that it be not inconsistent with any defense requirements of the United States or of its possessions, to communicate or transmit to the government of any American republic or to any duly authorized person for the use of such government information pertaining to the arms, ammunition, or implements of war sold under the terms of that section or to any vessels of war constructed within the jurisdiction of any such government, and to export for the use of any such government coast defense and antiaircraft matériel and ammunition therefor, and vessels of war and their armament and equipment involving such information: Provided, That any information thus communicated or transmitted or involved in any such arms, ammunition, implements of war, or equipment when exported shall cease to be considered restricted after one year from the date that such communication or transmission has been authorized or such exportation made.

All contracts or agreements made by the Secretary of the Army or the Secretary of the Navy for the sale to the government of any American republic of any of the arms, ammunition, or implements of war, the sale of which is authorized by this subchapter, shall contain a clause by which the purchaser undertakes not to dispose of such arms, ammunition, or implements of war, or any plans, specifications, or information pertaining thereto, by gift, sale, or any mode of transfer in such manner that such arms, ammunition, implements of war, or plans, specifications, or information pertaining thereto, may become a part of the armament of any state other than an American republic.

The Secretary of the Army or the Secretary of the Navy, as the case may be, shall, when any arms, ammunition, implements of war, or equipment are exported pursuant to the provisions of this subchapter, immediately inform the Secretary of State, Chairman of the National Munitions Control Board, of the quantities, character, value, terms of sale, and destination of the arms, ammunition, implements of war, or equipment so exported. Such information shall be included in the annual report of the Board.

The Secretary of the Army and the Secretary of the Navy shall in all contracts or agreements for the sale of such matériel fully protect the rights of all citizens of the United States who have patent rights in and to any such matériel which is authorized to be sold and the funds collected for royalties on such patents shall be paid to the owners and holders of such patents.

The Secretaries of the Army and of the Navy are authorized to purchase arms, ammunition, and implements of war produced within the jurisdiction of any American republic if such arms, ammunition, or implements of war cannot be produced in the United States.