JUDGMENT

BHAGWATI, J. :—This appeal by special leave is directed against an award made by the Industrial Tribunal, Calcutta in a reference between the National and Grindlays Bank Ltd. (hereinafter referred to as the Bank) and its workmen represented by the All India National and Grindlays Bank Employees Federation. The Bank is a banking company within the meaning of Section 5 of the Banking Companies Act, 1949 and has its Head Office in London and branch office in different parts of the world, including India. The principal office of the Bank in India is situate in Calcutta. The Bank maintains its accounts according to the calendar year and it brings out not only a consolidated balance sheet and profit and loss account for its world business, but also a separate balance sheet and profit and loss account for its Indian business. There was an industrial dispute between the Bank and its workmen in regard to bonus for the years 1956 to 1964 and as a result of negotiations, this industrial dispute was settled between the parties on an ad hoc basis under a Memorandum of Settlement dated 28th December, 1965. The material terms of the settlement were :

"1. The Bank will pay and the workmen and non-workmen staff will receive a sum of Rs. 27 Lakh (Rupees twentyseven lakhs only) in full and final settlement of all bonus claims covering the periods from 1st January 1956 to 31st December, 1964, including any claims relating to Centenary Bonus.

2. The above sum of Rs. 27 lakhs will be allocated as to one-third thereof to Award-staff only and as to the remaining two-thirds to both the Award and non-Award staff, in both cases based on the basic salary paid over the period, namely 1st January, 1956 to 31st December, 1964, and unrelated to any particular year.

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8. The parties agree that this Settlement shall not be taken as the basis or govern the principle for this determination of bonus in future, but nevertheless this Settlement shall be final and binding on the parties as regards bonus claims for the years 1956 to 1964 (both inclusive) and any claim relating to Centenary Bonus, as also regards qualifications for eligibility and procedure as set out above." It may be noted that this Settlement was arrived at between the parties after the Payment of Bonus Act, 1965 came into force on 25th September, 1965. This Act provided a statutory formula for computation and payment of bonus and it was admittedly applicable in respect of the accounting year 1964, but no separate computation of bonus for that year was made in accordance with this statutory formula and it was settled on an ad hoc basis as a part of an omnibus settlement for the accounting years 1956 to 1964. So far as the claim for bonus for the accounting year 1965 was concerned, computation was made in accordance with the statutory formula provided in the Payment of Bonus Act and the maximum 28 of the salary or wage earned during that accounting year was paid by way of bonus to the workmen. The claim for bonus for the accounting year 1966, however, could not be settled between the parties and though the Bank paid 18 of the wage or salary earned by the workmen during that accounting year as 613 bonus, the workmen were not satisfied and the industrial dispute arising from their claim had to be referred for adjudication. There were different aspects of this industrial dispute which required consideration and the Central Government, therefore, formulated each aspect as a separate question and referred those questions for adjudication to the Industrial Tribunal, Calcutta. The Industrial Tribunal made an award holding that, on an application of the statutory formula, the amount available for payment of bonus was Rs. 22.17 lakhs and the workmen were, therefore, entitled to a little over 9 of their salary or wage as bonus, but since they had already been paid by the Bank bonus at the rate of 18 of their salary or wage, which was much more than what they were entitled to receive, nothing fu