Utah Code § 81-5-303: Denial of paternity.

(1) A presumed or declarant father may sign a denial of the presumed or declarant father's paternity.

(2) The denial is valid only if:

(a) a declaration of paternity signed, or otherwise authenticated, by another man is filed in accordance with Section 81-5-305;

(b) the denial is in a form prescribed by and filed with the Office of Vital Records and Statistics and is signed, or otherwise authenticated, under penalty of perjury; and

(c) the presumed or declarant father has not previously:

(i) declared the presumed or declarant father's paternity, unless the previous declaration has been rescinded in accordance with Section 81-5-306 or successfully challenged in accordance with Section 81-5-307; or

(ii) been adjudicated to be the father of the child.