Md. Code, Real Property § 13-504

(a) Subject to subsection (b) of this section, if, after the exhaustion of all available defenses and appeals, a court of competent jurisdiction determines that the patent is invalid as to any portion of the vacant land for which it was issued, the person to whom the patent was issued is entitled to reimbursement from the State of that portion of the entire purchase price paid that is equitably attributable to the vacant land held to have been invalidly patented, based on a pro rata apportionment of the entire purchase price or any other factor which the Board of Public Works determines to be relevant.

(b) Any person claiming a right to reimbursement under this section shall apply to the Board of Public Works for reimbursement within six months of the final court decision on which the claim is based. The application shall set forth in detail the basis of the claim. It shall be signed and verified by the person making the claim and contain a certification that a copy of the application was mailed to the Commissioner.

(c) If the Board of Public Works determines that the applicant is entitled to reimbursement under this section, it shall establish the amount of the reimbursement, provide for payment of the reimbursement from funds available to it, and make the reimbursement as soon as is practicable.