Section 14
SEC. 14. Tha rates charged by the grantee, his successors, or aasigns shall be subject to regulation by the BOard of Public Utility Commissioners or its successors, and the right is hereby reserved to the Government of the Philippine Islands to regulate the rates to be charged by the grantee, his successors or assign, but any rates which shall be fixed shall be sufficient to yield a reasonable return to the grantee, his successors or assigns upon the capital invested after making due allowance for maintenance, operation, and other necessary expenses.