Mo. Rev. Stat. § 375.1800: Residency of insurance companies, domestic and foreign.

1. A domestic insurance company shall be deemed for all purposes, including venue, to reside in, and be a resident of, the county where its registered office is maintained.

2. A foreign insurance company shall be deemed for all purposes, including venue, to reside in, and be a resident of, the county where its registered office is maintained. A foreign insurance company that does not maintain a registered office in any county in Missouri shall be deemed to reside in, and be a resident of, Cole County.