Mo. Rev. Stat. § 109.500

"Records", as used in sections 109.500 and 109.510, means documents, books, papers, photographs, maps, sound recordings, or other material, regardless of physical form or characteristics, made or received pursuant to law or in connection with the transaction of official business. Library museum material made or acquired and preserved solely for reference or exhibition purposes, extra copies of documents preserved only for convenience of reference, and stocks of publications and of processed documents are not included within the definition of records as used in sections 109.500 and 109.510, and are hereinafter designated as "nonrecord" materials; and any record designated or treated as a record under state law.