Capital gains exemption on shifting an industrial undertaking to an SEZ depends on timely reinvestment, deposit compliance, and three-year recapture rules. Capital gains exemption is available on transfer of plant, machinery, building, land or rights in building or land used by an industrial undertaking situated in an urban area, where the undertaking is shifted to a Special Economic Zone. Relief depends on investment in new assets within the prescribed period, with partial exemption where the new asset cost is lower than the capital gain and full exemption where it equals or exceeds the gain. Unutilised capital gain must be deposited under the notified deposit scheme and becomes taxable if not applied within three years.