Maryland Code, FAMILY LAW 5-3A-06
(1) the man was married to the child’s mother at the time of the child’s conception;
(2) the man was married to the child’s mother at the time of the child’s birth;
(3) the man is named as the father on the child’s birth certificate and has not signed a denial of paternity;
(4) the child’s mother has named the man as the child’s father and the man has not signed a denial of paternity;
(5) the man has been adjudicated to be the child’s father;
(6) the man has acknowledged himself, orally or in writing, to be the child’s father and the mother agrees; or
(7) on the basis of genetic testing, the man is indicated to be the child’s biological father.
(b) (1) A petitioner under this subtitle shall give a court notice that a man who is not named in the petition and has not been excluded as a father claims paternity.
(2) After a request of a party or claimant and before ruling on a petition for guardianship or adoption under this subtitle, a court shall hold a hearing on the issue of paternity.