Google has agreed to pay parents at least $19 million to refund the unauthorized in-app purchases made by their kids, according to the Sydney Morning Herald.

The issue started in 2011 when parents started receiving billing notices from Google about the in-app purchases of their children while using mobile apps.

The virtual purchases were made through Google Play for Android mobile devices. The items bought range from 99 cents to $200.

After receiving the notices, many parents complained that they never gave authorization to their kids to make the purchases.

According to the Federal Trade Commission (FTC), the company has promised to improve its billing procedures for in-app purchases.

Specifically, the FTC said Google will "ensure that it obtains express, informed consent from consumers before charging them for items sold in mobile apps."

The U.S. agency also noted that it is the responsibility of companies to ensure that their customers are billed properly for their transactions.

"As more Americans embrace mobile technology, it's vital to remind companies that time-tested consumer protections still apply, including that consumers should not be charged for purchases they did not authorize," FTC's chairperson, Edith Ramirez said.

Google's refund program will only apply to consumers in the United States. Before it issues the refunds, the company will contact all of its consumers who were billed for unauthorized transactions, CNET reported.

"We're glad to put this matter behind us so we can focus on creating more ways for people to enjoy all the entertainment they love," a Google spokesperson said in a statement.

Google is not the first company to issue a massive refund amount to consumers due to inappropriate billing practices.

In January of this year, Apple paid a minimum of $32.5 million to consumers for charging them with unauthorized transactions, according to the Wall Street Journal.

Amazon was involved in a similar case in July after the FTC filed a complaint against the company. The agency alleged that Amazon billed parents for the unauthorized app purchases made by their children while using the Kindle Fire and the company's other devices.