MO Rev Stat § 375.788 (2021)
2021 Missouri Revised Statutes|Title XXIV - Business and Financial Institutions|Chapter 375 - Provisions Applicable to All Insurance Companies|Section 375.788 - Transaction of insurance business by unauthorized insurer, effect of.

Effective - 28 Aug 1972   375.788. Transaction of insurance business by unauthorized insurer, effect of. — 1. Any act of transacting an insurance business as set forth in section 375.786 by any unauthorized insurance company is equivalent to and shall constitute an irrevocable appointment by such insurance company, binding upon him, his executor or administrator, or successor in interest if a corporation, of the secretary of state or his successor in office, to be the true and lawful attorney of such insurance company upon whom may be served all lawful process in any action, suit, or proceeding in any court by the director of the department of commerce and insurance or by the state, and upon whom may be served any notice, order, pleading or process in any proceeding before the director of the department of commerce and insurance and which arises out of transacting an insurance business in this state by such insurance company. Any act of transacting an insurance business in this state by any unauthorized insurance company shall be signification of its agreement that any such lawful process in such court action, suit, or proceeding and any such notice, order, pleading or process in such administrative proceeding before the director of the department of commerce and insurance so served shall be of the same legal force and validity as personal service of process in this state upon such insurance company.  2. Service of process in such action shall be made by delivering to and leaving with the secretary of state, or some person in apparent charge of his office, two copies thereof and by payment to the secretary of state of the fee prescribed by law. Service upon the secretary of state as such attorney shall be service upon the principal.  3. The secretary of state shall forthwith forward by certified mail one of the copies of such process or such notice, order, pleading, or process in proceedings before the director to the defendant in such court proceeding or to whom the notice, order, pleading, or process in such administrative proceeding is addressed or directed at its last known principal place of business and shall keep a record of all process so served on him which shall show the day and hour of service. Such service is sufficient, provided:  (1) Notice of such service and a copy of the court process or the notice, order, pleading, or process in such administrative proceeding are sent within ten days thereafter by certified mail by the plaintiff or the plaintiff's attorney in the court proceeding or by the director of the department of commerce and insurance in the administrative proceeding to the defendant in the court proceeding or to whom the notice, order, pleading or process in such administrative proceeding is addressed or directed at the last known principal place of business of the defendant in the court or administrative proceeding.  (2) The defendant's receipt or receipts issued by the post office with which the letter is registered, showing the name of the sender of the letter and the name and address of the person or insurance company to whom the letter is addressed, and an affidavit of the plaintiff or the plaintiff's attorney in court proceeding or of the director of the department of commerce and insurance in administrative proceeding, showing compliance therewith, are filed with the clerk of the court in which such action, suit, or proceeding is pending or with the director in administrative proceedings, on or before the date the defendant in the court or administrative proceeding is required to appear or respond thereto, or within such further time as the court or director of the department of commerce and insurance may allow.  4. No plaintiff shall be entitled to a judgment or a determination by default in any court or administrative proceeding in which court process or notice, order, pleading or process in proceedings before the director of the department of commerce and insurance is served under this section until the expiration of forty-five days from the date of filing of the affidavit of compliance.  5. Nothing in this section shall limit or affect the right to serve any process, notice, order, or demand upon any person or insurance company in any other manner now or hereafter permitted by law. ­­-------- (L. 1972 H.B. 1264 § 375.785)