California Code, Family Code - FAM § 7648

(a) The age of the child.

(b) The length of time since the entry of the judgment establishing parentage.

(c) The nature, duration, and quality of any relationship between the previously established father and the child, including the duration and frequency of any time periods during which the child and the previously established father resided in the same household or enjoyed a parent and child relationship.

(d) The request of the previously established father that the parent and child relationship continue.

(e) Notice by the biological father of the child that the biological father does not oppose preservation of the relationship between the previously established father and the child.

(f) The benefit or detriment to the child in establishing the genetic father as the parent of the child.

(g) Whether the conduct of the previously established father has impaired the ability to ascertain the identity of, or get support from, the biological father.

(h) Additional factors deemed by the court to be relevant to its determination of the best interest of the child.