The assessee, a co-operative society engaged in providing banking and credit facilities to its members, inadvertently claimed deduction under section 80P(2)(c) instead of section 80P(2)(a)(i) in its return of income. Although a rectification application was filed, the same was not considered, and the Commissioner (Appeals) rejected the claim by invoking section 80A(5). The Tribunal held that the Assessing Officer is duty-bound to grant a legitimate deduction even if it is claimed under an incorrect provision or omitted due to a bona fide mistake. Further, section 80A(5) has no application to a deduction claimed under section 80P by a co-operative society. Accordingly, the assessee was held entitled to deduction under section 80P(2)(a)(i). (AY. 2018-19)