Mo. Rev. Stat. § 472.435: Catalogue of electronic communications disclosed to personal representative, when.

Unless the user prohibited disclosure of digital assets or the court directs otherwise, a custodian shall disclose to the personal representative of the estate of a deceased user a catalogue of electronic communications sent or received by the user and digital assets, other than the content of electronic communications, of the user, if the representative gives the custodian:

(1) A written request for disclosure in physical or electronic form;

(2) A certified copy of the death certificate of the user;

(3) A certified copy of the letters testamentary or letters of administration of the representative or a certified copy of certificate of clerk in connection with a small-estate affidavit or court order; and

(4) If requested by the custodian for the purpose of identifying the correct account of the correct user:

(a) A number, username, address, or other unique subscriber or account identifier assigned by the custodian to identify the user's account;

(b) Evidence linking the account to the user;

(c) An affidavit stating that disclosure of the user's digital assets is reasonably necessary for administration of the estate; or

(d) A finding by the court that:

a. The user had a specific account with the custodian, identifiable by the information specified in paragraph (a) of this subdivision; or

b. Disclosure of the user's digital assets is reasonably necessary for administration of the estate.