GST exemption for transfer of development rights and FSI with apportioned liability on un booked residential units at completion. The amendment adds exemptions from state GST for services by way of transfer of development rights or FSI and for upfront amounts for long term land lease where used for construction of residential apartments intended for sale, with the exempt amount apportioned by the ratio of residential carpet area to total project carpet area. Promoters remain liable on reverse charge for proportions attributable to residential apartments that remain un-booked at completion or first occupation, subject to capped rates, and the liability arises on completion or first occupation. Deemed valuation and defined terms for apartment, promoter, project and carpet area are prescribed.