Maryland Code, Estates and Trusts § 17-106

(a)(1) The death, disability, or incompetence of a principal who has executed a power of attorney in writing does not revoke or terminate the agency as to the attorney in fact, agent, or other person who, without actual knowledge of the death, disability, or incompetence of the principal, acts in good faith under the power of attorney or agency.

(2) Unless otherwise invalid or unenforceable, any action taken by the attorney in fact, agent, or other person who acts in good faith under the power of attorney or agency binds the principal and the principal's heirs, legatees, and personal representatives.

(b)(1) In the absence of fraud, an affidavit executed by the attorney in fact or agent and stating that the attorney in fact or agent did not have, at the time of doing an act in accordance with the power of attorney, actual knowledge of the revocation or termination of the power of attorney by death, disability, or incompetence, is conclusive proof of the nonrevocation or nontermination of the power at that time.

(2) If the exercise of the power requires execution and delivery of any instrument that is recordable, the affidavit when authenticated for record is likewise recordable.