Approval required before utility may guarantee another’s indebtedness. No public utility shall assume any obligation or liability as guarantor, indorser, surety or otherwise in respect to the securities of any other person, firm or corporation, when such securities are payable at periods of more than 12 months after the date thereof, without first having secured from the Public Utility Commission an order authorizing it so to do. Every assumption made other than in accordance with such an order is void

ORS 757.440 — under Chapter 757.