Does a sperm or egg donor need to sign anything to avoid future parentage obligations?

Yes. To avoid being considered a legal parent, a person who provides sperm, eggs, or embryos for someone else's reproduction should sign a written agreement, made before conception, stating that they do not intend to be a parent of any resulting child. Without this kind of agreement in place beforehand, a donor has no automatic protection from later being found a legal parent, particularly where the donor is known to the recipient rather than an anonymous clinic donor and there is an ongoing relationship or involvement in the child's life.

The agreement doesn't need to be elaborate, but it should be clear about the donor's intended role, be signed before conception occurs, and ideally be reviewed with independent legal advice so both the donor and the recipient parent understand what they're agreeing to. This matters just as much for the recipient parent, since an agreement that turns out to be unenforceable or poorly drafted can leave the child's parentage genuinely uncertain. Anyone arranging a private donor conception outside a fertility clinic should treat this agreement as a required step, not an optional formality.