Income exemption under Section 10(23C)(iv) excludes income received on behalf of the Defence Civilians Medical Aid Fund subject to conditions. Any income received by any person on behalf of Defence Civilians Medical Aid Fund, New Delhi shall not be included in the total income of such person for assessment years 1999-2000 to 2001-02, provided the Institution applies or accumulates its income wholly and exclusively to its objects (with accumulation beyond fifteen percent limited to five years), confines investments to permitted modes, treats business income as excluded unless incidental and separately accounted, files returns regularly, and on dissolution transfers surplus to a like-minded organisation.