US regulators unveiled new regulations December 19 aimed at strengthening online privacy protections for children, to reflect the growing use of mobile apps and social networks.
The Federal Trade Commission said its updated rules require websites or online services to get consent from parents if they are directed to children under 13 or if they have knowledge that they are collecting personal information from young children.
But FTC chairman Jon Leibowitz said the final rules in the Children's Online Privacy Protection Act stepped back from some earlier proposals, which would have made companies liable for most "plug-ins" such as the Facebook "like" button or Twitter's "tweet" button.
"The Commission takes seriously its mandate to protect children's online privacy in this ever-changing technological landscape," said Leibowitz.
"I am confident that the amendments to the COPPA Rule strike the right balance between protecting innovation that will provide rich and engaging content for children, and ensuring that parents are informed and involved in their children's online activities."
Liebowitz told reporters that websites will still be able to direct ads to children, and that "the only limit we place is on behavioural advertising," which is based on a person's browsing activity.
"Until you get parental consent, you may not build massive profiles of children to deliver advertising," the regulator said.
The rules close some loopholes on online operators who can be liable for violations of the law, which was passed by Congress in 1998.
But the regulations noted that in light of comments received on draft proposals, the FTC decided that the rules should not encompass platforms, such as Google Play or the App Store, that offer access to "someone else's child-directed content."
Third-party plug-ins would be responsible only where they have "actual knowledge that they are collecting personal information from users of a child-directed site," the FTC rules state.