Section 15
SEC. 15. The grantee may, with the prior approval of the Public Utility Commission, sell, lease, give, grant, convey, or assign the usufruct of, this franchise and all property and rights acquired thereunder to any person or corporation : Provided. That for the purpose of the sale, lease, donation, grant or transfer, it shall be necessary to file in the office of the Secretary of Commerce and Communications an agreement in writing by which the purchaser, lessee, donee or assignee shall bind himself to comply with all the terms and conditions imposed on the grantee by the franchise and shall accept the franchise subject to all its existing terms and conditions.