The Federal Trade Commission on Wednesday filed suit against Amazon in the U.S. District Court for the Western District of Washington, alleging a number of deceptive practices around its Prime membership program. 

The FTC charges that Amazon duped consumers into enrolling in Prime or opting for automatic renewals and made it difficult to cancel the subscription, according to its complaint. An Amazon Prime membership costs $139 per year or $14.99 per month. 

“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 in a statement. “These manipulative tactics harm consumers and law-abiding businesses alike. The FTC will continue to vigorously protect Americans from ‘dark patterns’ and other unfair or deceptive practices in digital markets.”

Dark patterns are user interfaces designed to induce online users or e-commerce customers to make choices they don’t want, often without them realizing it.

In an emailed statement, an Amazon spokesperson disputed the FTC’s assertions.

“The FTC’s claims are false on the facts and the law. The truth is that customers love Prime, and by design we make it clear and simple for customers to both sign up for or cancel their Prime membership,” the spokesperson said. “As with all our products and services, we continually listen to customer feedback and look for ways to improve the customer experience, and we look forward to the facts becoming clear as this case plays out.”

The spokesperson also said the agency filed its suit without warning, in the midst of ongoing discussions about the issues at hand, and that “we look forward to proving our case in court.”