Income exemption for donations: income received on behalf of Association of Tribal Welfare Development exempted subject to statutory conditions. Income received by any person on behalf of Association of Tribal Welfare Development, Naharbari, Dimapur, Nagaland is exempt under Section 10(23C)(iv) for assessment years 2006-07 to 2008-09, subject to conditions: income must be applied or accumulated exclusively for institutional objects with any excess accumulation over 15% limited to five years; funds must be invested only in forms specified in section 11(5) (except certain voluntary contributions); business income is taxable unless incidental and separately accounted; the Institution must file returns regularly; and on dissolution surplus assets must transfer to a like-minded organisation.