D.C. Mun. Regs. tit. 9, r. 9-211
Any bank or trust company, dealer in securities, real estate broker, storage company, or other person holding a joint deposit or account of the value of three hundred dollars ($ 300) or more in the name of a decedent and another person or persons, shall notify the Deputy Chief Financial Officer in writing of that fact immediately on learning of the decedent's death.
The notice shall contain the names and addresses of the decedent and each of the survivors to whom the joint deposits, accounts, or assets comprising those joint deposits or accounts shall have passed by right of survivorship, together with the date of death of the decedent, the value and character of the joint deposit, joint account, and assets as of the date of death of the decedent.
Similar notice to the Deputy Chief Financial Officer shall also be given by any insurance company or other person which has issued to a resident decedent an annuity policy or annuity contract which was in effect at the time of the death of the decedent and under the terms of which payments are to continue to a survivor or survivors.
D.C. Mun. Regs. tit. 9, r. 9-211