D.C. Code § 26-110

It shall be lawful for any notary public who is a stockholder, director, officer, or employee of a bank, trust company, or other corporation to take the acknowledgment of any party to any written instrument executed to or by such corporation, or to administer an oath to any other stockholder, director, officer, employee, or agent of such corporation, or to protest for nonacceptance or nonpayment drafts, checks, notes, acceptances, or other negotiable instruments which may be owned or held for collection by such corporation; provided, that it shall be unlawful for any notary public to take the acknowledgment of an instrument executed by or to bank or corporation of which he is a stockholder, director, officer, or employee, where such notary is a party to such instrument, either individually or as a representative of such corporation, or to protest any negotiable instrument owned or held for collection by such corporation, where such notary is individually a party to such instrument; provided further, that it shall be unlawful for any notary public to take the oath of an officer or director of any bank or trust company of which he is an officer, or to take an oath of any person verifying a report of such bank or trust company to the Comptroller of the Currency or the Superintendent of Banking and Financial Institutions [Commissioner of the Department of Insurance, Securities, and Banking], whichever is appropriate.