In this batch of writ petitions, the valid, "type of the provisions contained in the U. P. Trade Tax Act, formerly known as the U. P. Sales Tax Act, 1948 (hereinafter REFERRED TO as "the U. P. Act"), relating to imposition of sales tax on works contracts has been challenged. Since these petitions involve common questions, they are being disposed of by a common judgment.

Before the, Constitution (Forty-sixth Amendment) Act, 1982, indivisible works contracts were not eligible to sales tax due to judicial pronouncements. To overcome this difficulty, the Constitution was amended and the Constitution (Forty-sixth Amendment) Act came into force with effect from February 3, 1983. It introduced clause (29a) to article 366, clause (b) of which is material which runs as follows :

" 366. Definitions.- In this Constitution, unless the context otherwise requires, the following expressions have the meanings hereby respectively assigned to them, that is to say -

(29a) tax on the sale or purchase of goods includes -

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

(b) a tax on the transfer of property in goods (whether as goods or in some other form) involved in the execution of a works c