K.M. v. E.G.
California Supreme Court
117 P.3d 673 (2005)
K.M. (plaintiff) and E.G. (defendant), a couple living together as registered domestic partners, used K.M.'s ova (at the suggestion of a fertility specialist, after E.G.'s own attempts at pregnancy failed) to conceive twins carried and delivered by E.G. in 1995; K.M. signed a clinic form waiving parental rights, and the parties disputed whether they intended K.M. to be a co-parent or merely a donor, though evidence showed the couple later married, jointly represented themselves as co-parents to family, friends, and the twins' school, and the twins' nanny considered both women mothers, even though K.M. never formally adopted the children, insured them, or named them as insurance beneficiaries. After the couple separated in 2001, K.M. sued for custody and visitation; the trial court and Court of Appeal ruled for E.G., and K.M. appealed further.
Whether a woman who donates ova to her domestic partner, with the couple living together and intending to jointly raise the resulting children, has standing to seek parental rights despite conflicting evidence about whether the donor was meant to be treated as a parent.