California Code, Family Code - FAM § 852

(a) A transmutation of real or personal property is not valid unless made in writing by an express declaration that is made, joined in, consented to, or accepted by the spouse whose interest in the property is adversely affected.

(b) A transmutation of real property is not effective as to third parties without notice thereof unless recorded.

(c) This section does not apply to a gift between the spouses of clothing, wearing apparel, jewelry, or other tangible articles of a personal nature that is used solely or principally by the spouse to whom the gift is made and that is not substantial in value taking into account the circumstances of the marriage.

(d) Nothing in this section affects the law governing characterization of property in which separate property and community property are commingled or otherwise combined.

(e) This section does not apply to or affect a transmutation of property made before January 1, 1985, and the law that would otherwise be applicable to that transmutation shall continue to apply.