A ruling handed down Tuesday gives parental rights to gay parents who raised children with their partners outside of marriage.

The New York State Court of Appeals said such parents can seek custody and visitation rights.

Plaintiff in the case is a lesbian woman who was raising a son with her fiancee. The relationship soured before New York began issuing marriage licenses to gay and lesbian couples in 2011.

Representing the non-biological mother – known simply as Brooke B. – were Lambda Legal, Blank Rome LLP and The LGBT Bar Association of Greater New York.

“[T]oday, we overrule Alison D. and hold that where a parent shows by clear and convincing evidence that the parties agreed to conceive a child and to raise the child together, the non-biological, non-adoptive partner has standing to seek visitation and custody under [New York's Domestic Relations law],” Judge Abdus-Salaam said in his majority opinion.

Susan Sommer, national director of constitutional litigation at Lambda Legal, called the ruling a “landmark change in New York for children born to same-sex [couples].”

“Prior to today's decision, New York law on this issue was tragically stuck in 1991, when the Court of Appeals ruled in the Alison D. case that non-biological, non-married, non-adoptive parents are legal strangers to the children they raised with a same-sex partner,” Sommer said.

A year after they met, Brooke and Elizabeth, her former partner, get engaged in 2007. The following year, Elizabeth became pregnant using an anonymous donor. Brooke remained involved in her son's life after the couple split up in 2010 until 2013, when Elizabeth abruptly cut off contact.