Retrospective exemption from service tax on government's profit petroleum share enables refunds for collected tax. Clause 105 provides a retrospective exemption from service tax on the Government's share of profit petroleum received as consideration for grants of licence or lease to explore or mine petroleum crude or natural gas for the period 1 April 2016 to 30 June 2017, mandates refund of tax collected that would not have been collected under the exemption, requires refund claims within six months from Presidential assent to the Finance Bill, 2018, and preserves prior refund procedures by treating the earlier Chapter V as having continued in force for refund purposes.