Gov. Code, § 67568

An indenture may include a clause prescribing a procedure by which the terms and conditions of the indenture may be subsequently amended or modified with the consent of the commission and the vote or written assent of the holders of a specified principal amount of the bonds issued and outstanding. Such clause may provide for meetings of bondholders and for the manner in which the consent of the bondholders may be given. Such clause shall specifically state the effect of such amendment or modification upon the rights of the holders of all of the bonds and interest coupons appertaining thereto, whether attached thereto or detached therefrom.

With respect to any clause providing for the modification or amendment of an indenture, the commission may agree that bonds held by the commission, by any department or agency of the State of California, or by any public corporation, shall not be counted as outstanding bonds, or be entitled to vote or assent, but shall, nevertheless, be subject to any such modification or amendment.