A federal court found Amazon liable for charging parents for unauthorized in-app purchases made by kids, siding with the Federal Trade Commission in a case that stretched back to 2014.

The key question in the legal battle was whether Amazon’s app store made it too easy for children to buy virtual goods with real money inside games labeled as “free” without parental permission.

Following the launch of the Amazon app store in 2011, the company fielded thousands of complaints about unauthorized charges made by children in apps where they could purchase virtual items, the FTC alleged in a suit seeking refunds for consumers.

The practice was unfair because the e-commerce giant’s disclosures about in-app purchases didn’t do enough to explain to consumers what they were authorizing, the agency argued.

Amazon, whose founder Jeff Bezos also owns The Washington Post, has changed the in-app purchase interface over the years and added more parental controls, according to court filings. It also said it refunded consumers who complained.

In a ruling Tuesday, a federal judge granted the FTC a summary judgment that found the tech giant responsible for the charges.

“(W)hile entering a password linking her Amazon account to a new device, a reasonable consumer unaware of the possibility of in-app purchases would not assume she was authorizing unforeseen charges,” U.S. District Judge John Coughenour wrote in his order.