Section 15
SEC. 15. The grantee, with the approval of the Philippine Legislature first had, may sell, lease, grant, convey, assign, give in usufruct, or transfer this franchise and all property and rights acquired thereunder to any individual, copartnership, private, public or quasi-public association, corporation, or joint-stock company competent to operate the business hereby authorized, but transfer of title to the franchise or any right of ownership or interest acquired under such sale, lease, grant, conveyance, assignment, gift in usufruct, or transfer shall not be effective even after such approval have been obtained until there shall have been filed in the office of the Public Service Commission or its legal successor an agreement in writing by which the individual, copartnership, private, public or quasi-public association, corporation, or joint-stock company in whose favor such sale, lease, grant, conveyance, assignment, gift in usufruct, or transfer is made, shall be firmly bound to comply with all the terms and conditions imposed upon the grantee by this franchise and by any and all certificates of public necessity and convenience theretofore issued by the Public Service Commission or its legal successor, and to accept the same subject to all existing terms and conditions.