527.110. When declaratory relief is sought, all personsshall be made parties who have or claim any interest which wouldbe affected by the declaration, and no declaration shallprejudice the rights of persons not parties to the proceedings.In any proceeding which involves the validity of a municipalordinance or franchise, such municipality shall be made a party,and shall be entitled to be heard, and if the statute, ordinanceor franchise is alleged to be unconstitutional, the attorneygeneral of the state shall also be served with a copy of theproceeding and be entitled to be heard.
(RSMo 1939 ยง 1136)(1978) Held, that city of Lake Ozark was not an interested party in action under Sawyer Act when it intervened in annexation proceeding brought by city of Osage Beach, even though Lake Ozark was attempting to annex the same land. No question concerning validity of Lake Ozark annexation was raised. State ex rel. City of Lake Ozark v. City of Osage Beach (A.), 568 S.W.2d 539.