Section 78B-15-307 - Challenge after expiration of period for rescission(1) After the period for rescission under Section 78B-15-306 has expired, a signatory of a declaration of paternity or denial of paternity, or a support-enforcement agency, may commence a proceeding to challenge the declaration or denial only on the basis of fraud, duress, or material mistake of fact.(2) A party challenging a declaration of paternity or denial of paternity has the burden of proof.(3) A challenge brought on the basis of fraud or duress may be commenced at any time.(4) A challenge brought on the basis of a material mistake of fact may be commenced within four years after the declaration is filed with the Office of Vital Records. For the purposes of this Subsection (4), if the declaration of paternity was filed with the Office of Vital Records prior to May 1, 2005, a challenge may be brought within four years after May 1, 2005.(5) For purposes of Subsection (4), genetic test results that exclude a declarant father or that rebuttably identify another man as the father in accordance with Section 78B-15-505 constitute a material mistake of fact.Renumbered and Amended by Chapter 3, 2008 General Session .