Mo. Rev. Stat. § 400.9-703: Security interest perfected before effective date.

(a) A security interest that is enforceable immediately before July 1, 2001, and would have priority over the rights of a person that becomes a lien creditor at that time is a perfected security interest under this act if, on July 1, 2001, the applicable requirements for enforceability and perfection under this act are satisfied without further action.

(b) Except as otherwise provided in section 400.9-705, if, immediately before July 1, 2001, a security interest is enforceable and would have priority over the rights of a person that becomes a lien creditor at that time, but the applicable requirements for enforceability or perfection under this act are not satisfied on July 1, 2001, the security interest:

(1) Is a perfected security interest for one year after July 1, 2001;

(2) Remains enforceable thereafter only if the security interest becomes enforceable under section 400.9-203 before the year expires; and

(3) Remains perfected thereafter only if the applicable requirements for perfection under this act are satisfied before the year expires.