Arizona Attorney General Kris Mayes filed a lawsuit against Amazon, accusing the company of using its Buy Box algorithm to harm consumers and unfairly disadvantage third-party sellers.

The lawsuit claims that Amazon's Buy Box algorithm, which determines which offer for a product is featured with the "Buy Now" or "Add to Cart" buttons, is misleading consumers, causing them to overpay for items as they are often directed to higher-priced options that generate more fees for Amazon.

It also accuses Amazon of harming smaller sellers and those not using FBA services are at a disadvantage, as their potentially better offers are less likely to be featured in the Buy Box.

The suit also alleges that Buy Box favours Amazon's own products or those from sellers using Fulfillment by Amazon (FBA) services, even when better non-FBA options are available, and it actually favours options that maximise Amazon's profits - contrary to what Amazon says publicly about the system.

The lawsuit argues that these practices violate Arizona's Consumer Fraud Act and Uniform State Antitrust Act by unfairly maintaining Amazon's market dominance.

Amazon denied these allegations, stating that the lawsuits mischaracterise how their business operates and that forcing changes would actually harm consumers and businesses selling on their platform.