O.C.G.A. § 44-5-12: Impeachment of grants; grounds; effect of irregularities or misnomer.

Grants may be impeached before the courts where they are:

(1) Void upon their face;

(2) Issued without authority of law or against a prohibition in a law; or

(3) Issued for property to which the state had no title.

However, mere irregularities in the proceedings to obtain grants shall not be inquired into nor may a mistake in the name of the grantee be proved by parol.