Nothing To Do With Lesbians

I'm seeing this story about a sperm donor forced to pay child support to two lesbians all over the place. People seem to be taking the line that the man in question is being unjustly used and it's all the crazy lesbians' fault. I completely disagree with that take; I think the homosexuality of the couple has nothing to do with the case (except in the general sense that the couple was in search of an experience for themselves more than concerned about a duty to the child they brought into being), which would be completely unaltered if an infertile heterosexual couple were involved instead. The question is: what are the moral duties of sperm donors?
A sperm donor has been ordered to pay child support for the biological daughter he fathered to a lesbian couple who found him via Craigslist.
Angela Bauer, 40, and partner Jennifer Schreiner, 34, placed an ad on the site three years ago for a donor which was answered by William Marotta.
'We are foster and adoptive parents and now we desire to share a pregnancy and birth together,' Bauer wrote in the online posting.
Mr Marotta provided sperm which was used for artificial insemination by Ms Schreiner. In return, he gave up parental rights including financial duties for the child. The three signed a legal document which stated Mr Marotta, a married mechanic who fosters children with his wife, would have no rights to the child.
Please note the lesbian couple didn't go after the guy. They're on his side. All they did was split up, and the mother, who has custody of the child, recently filed for welfare benefits because she has some health problems that have made it hard for her to work.

It's the state, specifically Child Protective Services, that went after the father as a way to get health care benefits for the child.

So this is not a case of mean old lesbians doing what they want until they change their minds and want something else. This is a case of two people hiring a sperm donor and the three of them making a life cavalierly and then expecting the state to take care of the consequences when they don't keep their commitments to each other. This is a case of the state stepping in to say that it will tolerate the libertarian approach to family life only so far --but when a child's welfare becomes enough endangered, you are going to be held responsible for lives you bring into being. Without having read the ruling -- judging solely by the outcome-- I'm inclined to think it's a sound ruling, actually: you don't get to engender life lightly. I hope it sets a precedent and reverberates across the sperm donor/ surrogate mother industry.