SACRAMENTO, Calif. -- A child custody case involving U.S. actor Jason Patric and his ex-girlfriend has grown into a heated battle in California about whether certain sperm donors should be granted parental rights.

Patric took his case to state lawmakers after a judge ruled that he had no parental rights to Gus, the 3-year-old son he conceived with Danielle Schreiber using in vitro fertilization. The resulting bill comes before a legislative committee Tuesday, and Patric is expected to testify.

The couple, who never married, offer different versions of what role Patric was to play in the child's life. Patric said he signed an "intended parent" document and spent significant time with the boy until Schreiber cut off access. Her attorneys say his involvement was based on dating Schreiber and not as the boy's intended father.

A judge determined that Patric met the definition of a sperm donor under state law and thus had no legal rights as the boy's father.

The author of that law, state Sen. Jerry Hill, says he is now trying to clarify his previous statute so unmarried men who contribute to assisted reproductive methods are not unfairly stripped of parental rights.

"This bill does not give me my son back," Patric told The Associated Press in an interview. "This bill allows me to come into a court of law and say, 'This is my son."'

Opponents have written letters to the committee, arguing that the bill could negatively affect the rights of same-sex couples or single mothers who use sperm donors to conceive.

They say the standards for involvement in the child's life are too broad under the bill and that it could upend existing relationships between women and sperm donors if the donor decides later to seek a legal role in the child's life.

The bill does not specifically rule out anonymous sperm donors from seeking parental rights but says any man who seeks those rights must demonstrate some kind of ongoing relationship with the child.

Schreiber's attorney, Fred Heather, said the legislation would make single mothers vulnerable to unnecessary lawsuits such as the one his client has been fighting.