You need to speak to an attorney -BUT- I believe if you are listed on the birth certificate as the child's father, you are legally the child's father. You may not actually be the biological father but you are the legal father as far as the law is concerned, if you see what I mean. I am almost positive that is the case. If that is the case, you will have the same legal rights as any true birth father would have. Put a call in to a lawyer that practices family law. He will advise you of your rights.