JUDGMENT

Bharucha, J.-The correctness of the judgment and order of a Division Bench of the High Court at Calcutta is under challenge in this appeal by the Commercial Tax authorities of the State of West Bengal.

2. The first respondent was the sole proprietory concern of the late Biswanath Jhunjhunwalla; the second respondent is his heir and legal representative. The first respondent carried on business, principally in gunny bags, and was a registered dealer under the Bengal Finance (Sales Tax) Act, 1941 (now called the Act ). We are concerned in this appeal with the assessments of the first respondent for the Assessment Years Chaitra Sudi 2023 and 2024. These assessments were completed on 17th February, 1969, and 26th March, 1969. Under the law as it then stood, namely, Rule 80, sub-rule (5) of the Bengal Sales Tax Rules, 1941, the assessments could have been re-opened only within a period of 4 years for the relevant part of sub-rule (5) read thus :

"(5) The Commissioner or any other authority to whom power in this behalf has been delegated by the Commissioner, shall not, of his own motion, revise any assessment made or order passed under the Act or the rules thereunder if -

xxx xxx xxx

(ii) the assessment has been made or the order has been passed more than four years previously."

The Bengal Sales Tax Ordinance, 1973, substituted sub-section (1) of Section 26 of the Act. As substituted, sub-section (1) of Section 26 read thus :

"26(1) The State Government may make rules, with prospective or retrospective effect, for carrying out the purposes of this Act."

The Ordinance was replaced by the Bengal Finance (Sales Tax) (Third Amendment) Act, 1974.

3. Pursuant to the amendment of Section 26(1) of the Act, a Government Notification was issued on 30th March, 1974, amending, "with effect from the 1st November, 1971", clause (ii) of sub-rule (5) of Rule 80. Subsequent to such amendment, the relevant part of sub-rule (5) read thus :

"The Commissioner or any other authority to whom power in this behalf has been delegated by the Commissioner shall not, of his own motion, revise any assessment made or order passed under the Act or the rules thereunder if -

xxx xxx xxx

(ii) the assessment has been made or the order has been passed more than six years previously."

4. On 7th November, 1974, the Commercial Tax authorities issued to the first respondent notices reopening its completed assessments for the Assessment Years Chaitra Sudi 2023 and 2024 under the provisions of the amended sub-rule (5) of Rule 80. The then proprietor of the 1st respondent filed a writ petition in the Calcutta High Court challenging the legality of these notices. The validity of the amendment of Section 26(1) of the Act was called in question, and was upheld. (This contention need not detain us because it is not pressed.) It was argued on behalf of the first respondent that the right to re-open the assessments dated 17th February, 1969, and 26th March, 1969, stood barred under the unamended provisions of Rule 80(5)(ii) when the said Notification amending these provisions was issued and, therefore, the notices were bad in law. The contention was upheld. The High Court held that, by the amendment of the rule, assessments which had been completed could be revised within 6 years of the date of such completion, but when the right to revise the assessments under the unamended provision of the rule stood barred on the date the amendment was made, such assessments could not be re-opened or revised. The said Notification did not either expressly or by necessary implication confer any power of revision of assessments which stood barred on the date on which it was issued. The High Court relied upon the decisions of this Court is S.S. Gadgil, Income-tax Officer, Bombay, v. Lal and Ors.1 and J.P. Jani, Income-tax Officer v. Induprasad Devshanker Bhatt.2 It quashed the notices.

5. Hence, this appeal by special leave.

Mr. Tapas Ray, learned counsel for the appellants, dre