Can a sperm donor be forced to pay child support?

No, Anyone willing to be the mother of a donated specimen's child is not entitled to child support. The laws that support such cases are for the protection of those who donate sperm. The key word here is "donate". Generally those who become mothers through a sperm bank have a financially stable background. Usually a Father figure that cannot produce enough sperm himself is along for the ride as well. The only people that you can sue for child support are those that have signed the birth certificate of the child. Sperm banks do not release the information of the donor's.

This is not exactly clear in that case law has not been established nor have appeal courts ruled on all the facets of this complicated issue. While in states that have established protection for sperm donors who have anonymity, later court action demanding child support for the sperm donor would be unlikely to succeed as long as anonymity was still in place. However, there are sperm donor banks that reveal the father's identity, a few even before the age of 18. The donor's subsequent relationship with the offspring could negate any protection provided by statue. For example, if a donor assumed a close relationship with the child, accepted the title of Daddy, and provided some financial support, regardless of regularity support, the Courts may well be inclined to rule in favor of the donor's role in future child support actions. A donor's relationship to the offspring he creates can well overcome any statute when he voluntarily decides to take on the role or approximate the role of "Daddy".

This is not something unknown in well established case law. The so called "milkman rule" certifies this. A husband suspicious of his wife's philandering, nonetheless, assumed the role of Dad for a child that was born to his wife. Years later when the child was 8 years old the couple divorced and the father, suspicious of his fatherhood, was able to prove in court he was not the genetic father. Nonetheless, he was ordered to pay child support. Whether your name as sperm donor appears on that child's birth certificate is not near as important as what role you play in that child's life. As is often the case, in law, no good deed will go unpunished.