JUDGMENT

KAPUR, J. –

This is a petition under Article 32 of the Constitution challenging the legality of the amendment introduced in section 150 the Assam Sales Tax Act, 1947 (Act XVII of 1947) by section 2 of the Assam Sales Tax (Amendment) Act, 1960 (Act XIII of 1960) by which sub-section (b) of item (i) of sub-clause (b) of clause (1) was deleted and thereby sales of goods to a registered dealer intended for use in production of goods for sale became liable to sales tax.

The appellant company is a limited company carrying on in the State of Assam its business of manufacturing, selling and supplying iron and steel materials. It held a registration certificate under the Assam Sales Tax Act, as it was before the amendment of 1960. Under that Act all its purchases for use in manufacture or production of goods taxable under the Act were exempt from sales tax but after the amendment of the Act there was a deletion in the registration certificate of certain goods, e.g., cast iron, iron plates, steel bars and galvanized wire, which were used by the petitioner in the manufacture of its finished products which are also taxable in the State. Consequently it has become liable to pay tax on those goods purchased for use in the manufacture of goods and the cost of production has thereby gone up.

Three points were raised by the petitioner :-

(1) that the amendment introduced by Act XIII of 1960 is violative of Article 14 because it discriminates between manufacturers who supply goods according to orders received and others who manufacture goods on their own account and sell them;

(2) that the restriction imposed by the Amending Act is excessive and violative of Article 19(1)(f); and

(3) that the refusal to amend the registration certificate by not reinstating the articles mentioned above affects the rights of the petitioner company under Article 19(1)(f).

For the purpose of deciding these questions it is necessary to refer to the scheme of the Assam Sales Tax Act, 1947 (Act XVII of 1947). By section 2(2)(a)(b) of that Act "contract" is defined as :-

"2. In this Act, unless there is anything repugnant in the subject or context, -

(2) 'contract' means any agreement for carrying out for cash or deferred payment or other valuable consideration -

(a) the preparation, construction, fitting out, improvement or repair of any movable property or of any building, road, bridge or other immovable property, or

(b) the installation or repair of any machinery affixed to a building or other immovable property."

Section 9 of that Act provides for compulsory registration. Section 12 provides that a dealer registered under section 9 shall be granted a certificate of registration which shall specify the class or classes of goods in which the said dealer carries on business, and such other particulars as may be prescribed. Section 15(1)(b)(i)(b) and (c) deals with exemptions. It reads :-

"15. The net turnover shall be determined, by deducting from a dealer's gross turnover during any given period -

(1) his turnover during that period on -

(a) .............................................

(b) sale to a registered dealer of -

(i) goods specified in the purchasing dealer's certificate of registration as being intended by him for -

(a) ..............................................

(b) use in manufacture or production of any goods, the sale of which is taxable under this Act,

(c) use in the execution of any contract."

Sub-clause (b) has now been omitted by the amending Act above referred to as a result of which "from the gross turnover of a dealer goods specified in the certificate of registration as being intended by him for use in manufacture or production of any goods for sale" has now been omitted.

The argument raised was that by the omission of sub-clause (b) discrimination was intended as between materials which were to be used for manufacture of goods and to be sold on their own account by the petitioner company and materials which were purchased for use