2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/72683We define comodule algebras and Galois extensions for actions of bialgebroids. Using just module conditions we characterize the Frobenius extensions that are Galois as depth two and right balanced extensions. As a corollary, we obtain characterizations of certain weak and ordinary Hopf-Galois extensions without reference to action in the hypothesis.5 pages, clarification of main theorem with thanks to the referee of Algebra Montpellier AnnouncementsQuantum AlgebraRings and Algebras13B05, 16W30text