S. 80P : Co-operative societies-Mutuality-Three classes of members, namely, regular members, associate members and nominal members-Mutuality cannot be denied-Interest from fixed deposit with co-operative Bank-Within mandatory limit allowed deduction-Rental income, commission and other income-Disallowance affirmed. [S. 40(a)(ia), 57, 80P(2)(a)(i), Karnataka Cooperative Societies Act, 1959,S. 18]