Sec. 18.
That section 9 of the "Shipping Act, 1916," is amended to read as follows:
"Sec. 9. That any vessel purchased, chartered, or leased from the board, by persons who are citizens of the United States, may be registered or enrolled and licensed, or both registered and enrolled and licensed, as a vessel of the United States and entitled to the benefits and privileges appertaining thereto: Provided, That foreign-built vessels admitted to American registry or enrollment and license under this Act, and vessels owned by any corporation in which the United States is a stockholder, and vessels sold, leased, or chartered by the board to any person a citizen of the United States, as provided in this Act, may engage in the coastwise trade of the United States while owned, leased, or chartered by such a person.
"Every vessel purchased, chartered, or leased from the board shall, unless otherwise authorized by the board, be operated only under such registry or enrollment and license. Such vessels while employed solely as merchant vessels shall be subject to all laws, regulations, and liabilities governing merchant vessels, whether the United States be interested therein as owner, in whole or in part, or hold any mortgage, lien, or other interest therein.
"It shall be unlawful to sell, transfer or mortgage, or, except under regulations prescribed by the board, to charter, any vessel purchased from the board or documented under the laws of the United States to any person not a citizen of the United States, or to put the same under a foreign registry or flag, without first obtaining the board's approval.
"Any vessel chartered, sold, transferred or mortgaged to a person not a citizen of the United States or placed under a foreign registry or flag, or operated, in violation of any provision of this section shall be forfeited to the United States, and whoever violates any provision of this section shall be guilty of a misdemeanor and subject to a fine of not more than $5,000, or to imprisonment for not more than five years, or both."