It is through the emptiness of an answer that we sometimes obtain the truth.
Adoptee Rights Law Center
Legal representation and advocacy for adult adopted people
What’s an Original Birth Certificate?
Most adopted persons know what an original birth certificate (OBC) is. Many non-adopted people do not. An original birth certificate is the initial birth certificate created shortly after a person's birth. For most people, it is their only birth certificate.
For persons born and adopted in the United States, a new or "amended" birth certificate replaces the OBC once the adoption is final. In addition to replacing the original, the names of the birth parents are also replaced with the names of the adoptive parents. Some states may also alter or omit additional information on a new certificate, including the adoptee's specific place of birth.
Depending on state law, an original birth certificate is sealed and remains unavailable to the adopted person, even when they become an adult. If you are not adopted, your original birth certificate is your only birth certificate---and it is always available to you upon request.