Deemed profits for specified goods: purchase treated as taxable business income with prescribed sectoral percentages and allocation rules. Section 44AC previously deemed a specified proportion of the purchase price of certain goods acquired by auction, tender or other modes to be the buyer's profits and gains from trading in those goods taxable under 'Profits and gains of business or profession.' It identified categories of goods with prescribed sectoral percentages, excluded bid money from 'purchase price,' limited application where sale price was state-fixed and non-auction, excluded further resale by buyers (with an exception for purchasers from public sector companies), and provided rules for apportioning expenses where businesses were mixed and separate accounts were not maintained.