A court battle over whether a sperm donor should pay a higher rate of child support has ended with a ruling that the man is liable because he has taken an active role in raising the children.

Kevin Zoernig had argued he was not required to pay child support because he is a sperm donor and is protected under the state's Uniform Parentage Act.

But the state Court of Appeals noted in its July 25 opinion that this was not a case involving an anonymous donor or a known donor who provided sperm to a licensed physician under an agreement in which he agreed to have no parental rights.

In this case, Janna Mintz inseminated herself using what the court describes as a "syringe-like implement."

The court said Thursday that the opinion, as a formal published opinion instead of a memorandum opinion, can be cited as a precedent.

Zoernig agreed in 1994 to donate sperm so that Mintz and her partner at the time, Deborah Mrantz, could have a child. After the couple broke up, Zoernig fathered another child for Mintz, again as a sperm donor.

Zoernig, Mintz and Mrantz had entered into an agreement in 1994 in which the female couple would be the child's primary custodians. Zoernig would serve as a male role model but not be financially obligated to support the child.

Mintz and Zoernig entered into a similar agreement for the second child, born in 1997, court records show.

Although Mintz is the children's primary custodian, they stay with Zoernig every other weekend during the school year and half the summer. Zoernig, 50, now is married and has three children with his wife.

In February 2000, Mintz sought child support payments from Zoernig. The parties agreed the following year that Zoernig would pay $250 a month in child support, plus $50 a month toward arrears, according to court documents.

In 2004, Mintz filed a motion to raise those payments, saying her financial situation had changed. A state district judge adopted a new rate of $670 a month.

Zoernig turned to the Court of Appeals, challenging his obligation to provide any support as well as the higher rate, since the children were conceived through artificial insemination.

The appellate court said he must pay support for both children.

The court said he "enjoys the rights of parenthood," and that the agreements entered into prior to conception "that purport to absolve him of his responsibility to pay child support" are not enforceable.

Mintz, who now has a husband, said she is pleased with the ruling.

"The decision represents a big victory for our children because their father will continue to provide support for them," she said in a statement.

Zoernig said the battle "shows you that people who make well-intended agreements outside of the court system can easily be swept into the court system."