AJJT K. SENGUPTA, J. ( 1 ) AT the instance of the Commissioner of Income-tax, the following question of law has been referred to this court under Section 256 (1) of the Income-tax Act, 1961, for the assessment year 1964-65 :"whether, on the facts and in the circumstances of the case, the Tribunal was correct in its finding that the order passed by the Income-tax Officer under Section 154 on April 5, 1979, was barred by limitation ?" ( 2 ) THE facts shortly stated are that, in the assessment for the assessment year 1964-65, there was a mistake in not charging additional tax on dividend distributed during the previous year ended December 31, 1963 (Rs. 5,62,000) by way of reduction in rebate of super tax in terms of the provisions of the Finance Act, 1964. Since the mistake was apparent from the record, the Income-tax Officer issued a notice under Section 154 dated March 19, 1979, for rectification of the order passed to give effect to the order made by the Tribunal under Section 254 of the Act on July 18, 1975, wherein the aforesaid mistake was committed. Accordingly, he passed the order under Section 154 on April 5, 1979. ( 3 ) BEING aggrieved by the order of rectification dated April 5, 1979, the assessee-company went in appeal to the Commissioner of Income-tax (Appeals) and took the ground that the order of rectification dated April 5, 1979, was bad inasmuch as it was barred by limitation. The Commissioner of Income-tax (Appeals) agreed with the assessee's counsel that the mistake had been committed in the original order and that the limitation started running from the date of the original order and the assessee's filing an appeal would not extend the Income-tax Officer's date of rectification of mistake allegedly made in the original order. The Commissioner of Income-tax (Appeals) held that the order of rectification dated April 5, 1979, was barred by limitation and the merits of the matter were not discussed. ( 4 ) AGAINST the said order of the Commissioner of Income-tax (Appeals ), the Revenue filed an appeal before the Tribunal. It was contended by the learned Departmental representative that the Commissioner of Income-tax (Appeals) was wrong in his finding that the period of limitation ran from the date of the original order which was passed on May 30, 1973. It was contended by the learned Departmental representative that the Commissioner of Income-tax (Appeals) was wrong in his finding that the period of limitation ran from the date of the original order which was passed on May 30, 1973. He urged that, while giving effect to the order of the Tribunal, the Income-tax Officer committed the same error which he had made in the original order. He urged that this was a patent mistake and that the same mistake crept into the order passed by the Income-tax Officer while passing an order to give effect to the order of the Tribunal on July 18, 1975. He, therefore, submitted that the order passed by the Income-tax Officer on July 18, 1975, was within the specified time and, therefore, the Commissioner of Income-tax (Appeals) was wrong in observing that the order was barred by limitation. The Tribunal upheld the order of the Commissioner of Income-tax (Appeals ). The Tribunal held as follows :"a perusal of the order passed by the Income-tax Officer under Section 154 dated April 5, 1979, would show that the Income-tax Officer himself stated therein that there was a mistake in the assessment in not charging additional tax on dividend distributed during the previous year ended December 31, 1963, by way of reduction in rebate of super tax in terms of the provisions of the Finance Act, 1964. This very fact goes to suggest that the Income-tax Officer sought to rectify the mistake in the assessment order that was made on May 30, 1973. Accordingly, it has to be held that the limitation for rectification of the mistake in the order dated May 30, 1973, expired on May 30, 1977, and, as such, the impugned order was prima facie beyond time. At the hearing before us, the contentions raised before the Tribunal have been reiterated. The question is whether the order passed by the Income tax Officer under Section 154 of the Income-tax Act, 1961, on April 5, 1979, is barred by limitation. " ( 5 ) THE facts are not in dispute. The original order of assessment was made by the Income-tax Officer on May 30, 1973. In the original order there was a mistake in the sense that rebate on super-tax was not reduced in accordance with the provisions of the Finance Act of 1964. " ( 5 ) THE facts are not in dispute. The original order of assessment was made by the Income-tax Officer on May 30, 1973. In the original order there was a mistake in the sense that rebate on super-tax was not reduced in accordance with the provisions of the Finance Act of 1964. The said order had been the subject-matter of appeal on another ground before the Appellate Assistant Commissioner and the Appellate Tribunal. The Income-tax Officer gave effect to the order of the appellate authority by his order dated July 18, 1975. The Income-tax Officer thereafter initiated proceedings for rectification on the ground that the allowance of the rebate on super-tax was not in accordance with law. ( 6 ) THE short question which calls for determination is whether the mistake if any, occurred in the original order dated May 30, 1973, or in the order dated July 18, 1975, which was passed by the Income-tax Officer while giving effect to the order of the appellate authority. If the mistake is in the original order, then the order of rectification is, on the face of it, barred by limitation. If, however, the mistake is in the subsequent order, that is to say, the order giving effect to the appellate order, in that event, it was not barred by limitation. The contention of Dr. Pal is that the mistake, if any, occurred in the original order dated May 30, 1973, and, accordingly, the order passed on April 5, 1979, is barred by limitation. If the original assessment order merges with the order of the appellate order in its entirety, in that event, the original order cannot be rectified by the Income-tax Officer. Section 154 (1a) specifically provides that where any matter has been considered and decided in any proceeding by way of appeal or revision relating to an order referred to in Sub-section (1), the authority passing such order may, notwithstanding anything contained in any law for the time being in force, amend the order under that sub section in relation to any matter other than the matter which has been so considered and decided. The assessee was not aggrieved by the original order passed by the Income-tax Officer in not reducing the rebate on super-tax in terms of the Finance Act, 1964. The assessee was not aggrieved by the original order passed by the Income-tax Officer in not reducing the rebate on super-tax in terms of the Finance Act, 1964. The matter was agitated by the assessee on other grounds before the Appellate Assistant Commissioner and the Tribunal. Therefore, the original assessment order, in so far as the rebate on super-tax was concerned remained unaffected by the appellate order. The Income-tax Officer could have rectified such mistake within four years which he did not do. The mistake is apparent on the face of the original assessment order. In other words, the said part of the order of the Income tax Officer did not merge with the order of the appellate authority. By rectification, the mistake that was in the original order is corrected and the correct state of affairs is restored. No rectification order can be passed after the expiry of four years from the date of order sought to be rectified because the date of the original order is the starting point of limitation where the original order does not merge with the order of the appellate authority. Even if the original order has been revised giving effect to the order of the appellate authority, the starting point of limitation would be the date of the original order and not the date of the order passed by the Income-tax Officer giving effect to the order of the appellate authority. ( 7 ) OUR attention has been drawn to the judgment of this court in the case of Bengal Assam Steamship Co. Ltd. v. CIT [1978] 114 ITR 327. In that case, the Income-tax Officer passed an order under Section 49a of the Indian Income-tax Act, 1922, granting certain reliefs to the assessee under the Agreement for Avoidance of Double Taxation between India and Pakistan. Thereafter, the Income-tax Officer passed an order under Section 154 by which he modified the earlier order granting certain reliefs under Section 49a of the old Act. The assessee, after 4 years from the date of the first order made under Section 49a, applied for rectification of certain mistakes in the assessment order. This was rejected on the ground that it was barred by limitation. The assessee came before this court on a reference. The assessee, after 4 years from the date of the first order made under Section 49a, applied for rectification of certain mistakes in the assessment order. This was rejected on the ground that it was barred by limitation. The assessee came before this court on a reference. This court held that the period of limitation will run from the date of the first order and not from the subsequent order passed by the Income-tax Officer rectifying the first order. ( 8 ) THE original order did not merge in the appellate order in respect of that part of the order which was not the subject-matter of appeal before the Appellate Assistant Commissioner or before the Appellate Tribunal. Hence, the mistake, if any, in the original order of assessment could be rectified only in the original order itself and not from the order which had given effect to the appellate order of the Appellate Assistant Commissioner or the Appellate Tribunal. In our view, so long as the original order remains unaffected and does not merge with the appellate order, the limitation will run from the date of the original order and not from the date when the Income-tax Officer has given effect to the order of the appellate authority. ( 9 ) FOR the reasons aforesaid, the question in this reference is answered in the affirmative and in favour of the assessee and against the Revenue. There will be no order as to costs.