In the crystal structure of the title compound, 2C(10)H(7)NO(4)·C(14)H(13)N(3)O(2), the two independent acid mol-ecules are connected through strong O-H⋯N and O-H⋯O hydrogen bonds to the central mol-ecule of the anti-tubercular drug N'-[(E)-4-meth-oxy-benzyl-idene]pyridine-4-carbohydrazide. Two such trimolecular units related by an inversion centre inter-act through a pair of N-H⋯O hydrogen bonds, forming a 3 + 3 mol-ecular aggregate. The dihedral angle between the aromatic rings of the hydrazone mol-ecule is 1.99 (12)°. The crystal packing features weak C-H⋯O and π-π stacking inter-actions, with centroid-centroid distances of 3.8460 (19) and 3.8703 (13) Å.