Tax exemption for government constituted blood transfusion trust approved for specified income, subject to conditions and time limits. Notification under clause (46) of section 10 designates the Gujarat State Council for Blood Transfusion as exempt for specified income - grants from state and central government, donations, and interest - subject to conditions that the trust does not engage in commercial activity, its activities and the nature of the specified income remain unchanged across the relevant financial years, and it files returns as required; applicability is limited to financial years 2013-14 through 2017-18.