hypnosec writes: Amazon sales revenue numbers in the UK have been huge over recent times. One in four books sold in the UK are through Amazon. It's Britain's biggest online retailer, and generated some £3.3 billion in sales last year. Yet the firm didn't pay any corporation tax on the profits made. However, the retail giant appears to be under HMRC investigation — or at least a filing by parent Amazon.com with the US securities and exchange commission indicates a tax inquiry of some sort is being conducted. In fact, the filing shows that in the past three years, Amazon has generated some £7.6 billion in sales in the UK, none of which has seen a penny of corporation tax paid.