Competition watchdog alleges supermarkets briefly increased prices on hundreds of products before placing them in discount promotions

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The competition regulator is suing Coles and Woolworths over allegations they misled shoppers by engaging in “illusory” discounts on hundreds of common supermarket products.

The Australian Competition and Consumer Commission (ACCC) claimed on Monday that the major chains derived significant revenue from the sale of tens of millions of products sold through promotions that the regulator says breached consumer law.