On appeal by the Revenue, the Tribunal upheld the view of the Appellate Controller relying on the decision of the Bombay High CoUrt in A.N. Mafatlal vs Deputy Controller of Estate Duty, Thereafter three references were made to the High Court at the instance of the Revenue raising the identical question: "Whether Section 59 of the is retrospective in operation and if so, in the facts and circumstances of the case, the reopening of the assessment under section 59 of the said Act was bad in law?" Section 62 as originally enacted read as follows: "Rectification of mistakes relating to valua tion for estate duty:, (1) If, after the determination of the estate duty payable in respect of any estate, it appears to the Controller that by reason of any mistake apparent from the record or of any mistake in the valuation of any property in any case other than a case in which the valuation has been the subject matter of an appeal under the Act or of the omission of any property, the estate duty paid thereon is either in excess of or less than the actual duty payable, he may, either on his own motion or on the appli cation of the person accountable and after obtaining the previous approval of the Board, at any time within three years from the date on which the estate duty was first determined (a) refund the excess duty paid, or, as the ease may be, (b) determined the additional duty payable on the property; Provided that where the person accountable had fraudulently under estimated the value of any property or omitted any property, the period will be six years: 991 Provided further that no order shall be made under this sub section unless the person accountable has been given an opportu nity of being heard.