These two code sections address the presumption of a child born during the marriage. If these code sections don’t make sense to you, consider a situation where unknown to the father, a child is born but it is not his. 5 years after the child is born, Wife files for divorce and discloses that Husband is not the father. Father has raised this child believing it was his and has created a very strong emotional bond with the child. It is not considered to be in the child’s best interest for the father to be forced out of the child’s life in that circumstance. It assumes the best in people and the idea that he will want to continue to be father.


(a) Except as provided in Section 7541, the child of spouses who cohabited at the time of conception and birth is conclusively presumed to be a child of the marriage.

(b) The conclusive marital presumption in subdivision (a) does not apply if the court determines that the husband of the woman who gave birth was impotent or sterile at the time of conception and that the child was not conceived through assisted reproduction.


(a) If the court finds that the spouse who is a presumed parent under Section 7540 is not a genetic parent of the child pursuant to Chapter 2 (commencing with Section 7550), the question of parentage shall be resolved in accordance with all other applicable provisions of this division, including, but not limited to, Section 7612.

(b) An action to challenge the parentage of the spouse who is a presumed parent under Section 7540 shall be filed not later than two years from the child’s date of birth and may only be filed by any of the following:

(1) By either spouse.

(2) By a person who is a presumed parent under Section 7611 or by the child, through or by the child’s guardian ad litem, to establish the parentage of the person who is a presumed parent under Section 7611.

(c) The petition or motion to challenge a presumption under Section 7540 pursuant to this section shall be supported by a declaration under oath submitted by the moving party stating the factual basis for placing the issue of parentage before the court.

(d) Genetic testing may not be used to challenge parentage, in either of the following cases:

(1) A case that reached final judgment of parentage on or before September 30, 1980.

(2) A case challenging the parentage of a spouse who is a parent pursuant to Section 7962 or subdivision (a) of Section 7613, except to resolve a dispute regarding whether the child was conceived through assisted reproduction.

(Amended by Stats. 2018, Ch. 876, Sec. 6. (AB 2684) Effective January 1, 2019.)