Interest on securities: definition clarifies which government and corporate instruments qualify for income-tax treatment. The statutory definition of Interest On Securities under clause (28B) of section 2 of the Income-tax Act identifies interest on securities of the Central or State Governments and interest on debentures or other money securities issued by or on behalf of a local authority, a company, or a corporation established by statute, thereby specifying the classes of issuers and instruments encompassed within this tax category.