In any offering or sale of a security which uses or refers to a lease for or on behalf of any state agency as collateral or security for payment, no state of Washington attorney general opinions or memoranda, or excerpts thereof, may be used or cited in any prospectus, offering circular or other written information provided to any prospective purchaser without the prior written approval of the treasurer. Such approval shall not be withheld if in the judgment of the treasurer such use of an opinion, memorandum or excerpt thereof would not be misleading by implying, directly or indirectly, that the state of Washington or any agency thereof is an obligor with regard to payment of the security. Notwithstanding the foregoing, nothing in this rule shall prevent the office of the attorney general from exercising any legal rights that it may have with respect to the use or publication by others of attorney general opinions or memoranda.