After years of court battles with the US Federal Trade Commission, Amazon has agreed to pay up to $70 million to parents whose kids made in-app purchases without permission.

The refunds began yesterday. Affected customers should be receiving an e-mail from Amazon. You can also check if you're owed a refund by clicking this Amazon link for "in-app refunds."

The FTC sued Amazon in 2014 , saying the company had insufficient safeguards preventing kids from making purchases, some of which ranged into the hundreds of dollars. When Amazon first launched its Kindle Fire OS, the default settings had parental controls turned off, while in-app purchases were allowed. Kids could charge their parents up to $99.99 for a single in-app purchase, often without needing a password, according to the FTC.

Last month, following Amazon losing a key court battle, the litigation was settled.

“This case demonstrates what should be a bedrock principle for all companies—you must get customers’ consent before you charge them,” said Thomas Pahl, acting director of the FTC’s Bureau of Consumer Protection.

The FTC believes that more than $70 million in charges incurred between November 2011 and May 2016 are eligible for refunds.

On this issue, Amazon was the last holdout among tech companies with large app stores. Similar FTC cases against Apple and Google were settled much more quickly, with both companies striking deals with the FTC in 2014. That year, Apple agreed to pay $32.5 million over kids' in-app purchases, while Google agreed to pay $19 million.