The US has accused Amazon of tricking customers into signing up for automatically renewing Prime subscriptions and making it difficult to cancel.
The Federal Trade Commission (FTC), the country’s consumer rights watchdog, made the claims in a lawsuit.
More than 200 million people globally subscribe to Prime, a subscription to Amazon that offers shipping perks, access to streaming movies and more.
Amazon did not comment immediately.
“Amazon tricked and trapped people into recurring subscriptions without their consent, not only frustrating users but also costing them significant money,” FTC Chair Lina Khan said announcing the suit, which was filed in federal court in Seattle.
The FTC said Amazon used website designs that pushed customers into agreeing to enrol in Prime and have the subscription automatically renew as they were making purchases.
According to the FTC, Amazon attempted to make it difficult for users to opt out of auto-enrolment because “those changes would also negatively affect Amazon’s bottom line”.
The company also allegedly put customers seeking to cancel through a cumbersome “four-page, six-click, fifteen option” process, which the FTC said was known internally as “Iliad” in a nod to the Greek epic about the “long, arduous Trojan War”.
The FTC said the company’s tactics broke laws aimed at protecting shoppers.
Amazon altered the cancellation process shortly before the lawsuit was filed, the agency added.
It is seeking a court order to force Amazon to change its practices, as well as financial penalties in an unspecified amount.
Prime costs $139 a year or $14.99 monthly in the US and £95 per year in the UK.
About 70% of subscribers are based in the US, according to the FTC.
The FTC has repeatedly warned online firms against using “dark patterns” to manipulate shoppers.
It had been investigating Amazon’s Prime programme since 2021.
It said the company had attempted to delay the probe on multiple occasions, including by refusing to deliver documents in a timely manner.
The lawsuit marks the third action from the FTC involving Amazon in recent weeks.
The company agreed to pay $25m last month to settle charges it had violated child privacy laws by keeping recordings children made on Alexa.
It agreed to pay another $5.8m to resolve claims that Ring, the doorbell company Amazon purchased in 2018, had violated privacy protections by giving staff unrestricted access to customer videos and failing to implement precautions against hackers.