Stier verified people's ages through information displayed in users' bios or profiles. He said he has seen teens say they're a "nonprofit," or an "athlete." But upon reviewing their profiles, he found that a significant portion of them were not businesses, but regular people, sometimes with mere hundreds of followers.
After he reported the issue to Facebook, Instagram made the contact information less obviously visible. But the company said they didn't consider his findings a security vulnerability because users made their own choices about what information to display, according to an email exchange reviewed by Bloomberg.
Instagram didn't reply to a request for comment.
Stier argued that despite that choice, Instagram could protect users' privacy. It's possible to email and call people without displaying their actual personal details. Many businesses use contact forms, for example, or anonymized emails. Instagram could do the same for minors, he said.
When people sign up to get Instagram's tools for businesses, the company doesn't verify that they are who they say they are. Instagram has blurred the lines between personal and professional, because so many regular people use their profiles for economic purposes, to create a brand for their art or photography or lifestyle.
But the metrics also matter to non-professional users. For the most part, users seek Instagram followings for the social currency they provide, creating something of a digital popularity contest. Instagram executives acknowledge the problem, and have proposed partially solving it by removing "like" counts on posts. The change is in testing in seven countries.
"We don't want Instagram to be such a competition," Chief Executive Officer Adam Mosseri said in June during an interview on CBS This Morning.