A lawsuit accused Amazon of violating US consumer protection by steering users of its website to higher-priced items commanding higher fees for the company, as opposed to the 'best' prices it claims. 

According to a legal complaint (pdf) filed in the name of two US-based customers of Amazon, the company's Buy Box algorithm often obscures lower-priced options with faster delivery times. 

The suit also cited a recent antitrust case against Amazon by the US Federal Trade Commission and 17 states which alleged that shoppers use the company's choices almost 98 percent of the time by clicking its 'Buy Now' or 'Add to Cart' buttons, often falsely believing it had identified the best prices. 

The lawsuit also accused Amazon of creating the algorithm to benefit third-party sellers that participate in its Fulfillment By Amazon programme, which pay 'hefty fees' for inventory storage, packing and shipping, returns and other services.