( 1 ) IN this group of petitioners, a common question of vires of Sec. 15-B of the Gujarat Sales Tax Act, 1969 as amended by Sec. 2 of the Gujarat Sales Tax (Amendment) Act, 1990 arises for consideration. It is the contention of the petitioners that the said provision is beyond the legislative competence of the State legislature. In order to appreciate this common grievance of the petitioners, it is necessary to note a few introductory facts :

( 2 ) I. Introductory facts : The petitioners are dealers registered under the provisions of the Gujarat Sales Tax Act, 1969 (the Act for short ). They carry on the activity of manufacturing and selling various goods in this State. For that purpose, they require raw materials which are to be used in manufacturing the end product. The materials purchased by them in the State and used in the manufacturing process have been subjected to purchase tax by the impugned provision. The petitioners contend that the State Legislature has no competence to impose such tax as such tax does not fall within any of the entries of List ii of the Seventh Schedule to the Constitution, viz. ,the State list especially Entry 54 thereof. They have joined in these petitions State of Gujarat as respondent no. 1 and the authorities exercising powers under the Act as other respondents. As the petitions involve common questions of law, they were all heard together and are being disposed of by this common judgment.

( 3 ) THE common grievance of the petitioners is required to be examined in the bacjground of the statutory settings and their historical backdrop.

( 4 ) II. Statutory setting : The Act has been enacted by the State legislature in exercise of its powers under Entry 54 of the State list. The said entry reads as under :"taxes on the sale or purchase of goods other than newspapers, subject to the provisions of Entry 92-A of List I". The said Act is operative in the State from 6-5-1970. By Sec. 2 of the Gujarat sales Tax (Third Amendment) Act, 1986, the legislature of the first respondent state had inserted Secs. 15b and 15c from 1-4-1986 in the Act providing in substance levy of tax on the taxable goods consigned by the dealer outside the state of Gujarat to the extent of 2% of the purchase price of the raw materials used in the manufacture of such taxable goods so consigned. However, by the gujarat Sales Tax (Amendment) Act, 1987, Sec. 15c was deleted from 1-4- 1987 and new Sec. 15b was substituted from 1-4-1987 for old section. New sec. 15b so substituted read as under:"where any dealer liable to pay tax under this Act uses any goods other than declared goods purchased by him or through commission agent as raw or processing materials or consumable stores (irrespective of whether such goods are prohibited goods or not) in the manufacture of taxable goods and despatches any of the goods so manufactured to his own place of business or to his agents place of business situate outside the State but within India such dealer will be liable to pay, in addition to any tax paid or payable under other provisions of this Act, a purchase taxat the rate of four paise in the rupee on the purchase price of such raw or processing materials or consumable stores used in the goods so manufactured and despatched and accordingly he shall include the purchase price thereof in histurnover of purchases in his declaration or return under Sec. 40 which he is to furnish next thereafter : provided that where the raw materia;s so used is bullion or specie, the purchase tax payable on such bullion or specie under this section shall not exceed the agreegate of the rates of Sales Tax and the General Sales Tax payable on bullion or specie. "a similar provision was operative in the Maharashtra State being Sec. 13aa of the Bombay Sales Tax Act, 1959. The said Bombay provision which was then existing read as under :"where a dealer, who is liable to pay tax under this Act, purchased any goods specified in Part I of Schedule C, directl