2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/128362We consider the Zassenhaus conjecture for the normalized unit group of the integral group ring of the Mathieu sporadic group M12. As a consequence, we confirm for this group the Kimmerle's conjecture on prime graphs.12 pages; bibliography updated; typos correctedRings and AlgebrasRepresentation Theory16S34; 20C05; 20D08text