Section 2
SEC. 2. Except in favor of the Government or any of its branches, units, or institutions, lands acquired under the provisions of this Act shall not be subject to encumbrance or alienation before the patent is issued and for a term of ten years from the date of the issuance of such patent, nor shall they become liable to the satisfaction of any debt contracted prior to the expiration of said period. No transfer or alienation made after the said period of ten years and within fifteen years from the issuance of such patent except those made by virtue of the right of succession shall be valid unless when duly authorized by the Secretary of Agriculture and Natural Resources and the transferee or vendee is a Filipino citizen. Every conveyance made shall be subject to repurchase by the original purchaser or his legal heirs within a period of five years from the date of conveyance. Any contract or agreement made or executed in violation of this section shall be void ab initio.