Keeping kids safe online is no easy task. As many as 25 percent of minors get away with pretending to be older on social networking sites like Twitter and Facebook, according to Netmums, and one in 12 sends messages with sexual content to other users. Worse still, roughly a third of children have been bullied, threatened, or abused online via email and instant messaging apps.

Those depressing statistics motivated Brian Bason, former chief technology officer at influencer collaboration platform Niche (which was acquired by Twitter), to take action. In 2015, he founded Bark, a service that leverages machine learning to identify potential safety concerns across text messages, emails, and 24 different social networks.

On the eve of its third birthday, the Atlanta-based startup is announcing a $9 million funding round led by Signal Peak Ventures, with Two Sigma Ventures and participation from existing investors, including Symmetrical Ventures, Fuel Capital, Hallett Capital, and Atlanta Seed Company. Bark will use the capital to “broaden its product offering” and “establish a presence in new markets,” Bason explained.

“We are very excited to welcome Signal Peak and Two Sigma as new investors and look forward to working closely with them, both to accelerate our growth and [to have a] positive impact on children’s lives,” he said in a statement.

Bark, which works on iOS, Android, and Amazon Fire Tablet devices, monitors kids’ communications in real time, automatically alerting parents to signs of depression, suicidal thoughts, cyberbullying, and adult content. The extensive list of supported apps includes Slack, Facebook, Twitter, WhatsApp, YouTube, Reddit, Pinterest, OneDrive, Kik, Houseparty, GroupMe, Google Drive, Flickr, Dropbox, Ask.Fm, and even Snapchat. And that’s all in addition to platform-level features that let parents monitor device location, photos, videos, and browsing history.

To be clear, Bark scans the content of kids’ phones and messages — even private messages. But it uses OAuth to connect social media accounts, meaning parents can deny it permission to access sensitive personal information, and Bark says it doesn’t store data on its servers.

To date, Bark said it has analyzed more than 1 billion messages across texting, email, and social media and that its algorithms are nuanced enough to distinguish between playful ribbing (“You suck!”) and real threats (“I’m going to beat you up for this”).

It normally runs $9 per month ($99 annually) per family. But following the high school shooting in Parkland, Florida earlier this year, Bark began offering its platform for institutions — Bark for Schools — free of charge to schools using Google’s G Suite for Education and Microsoft Office 365 Education. (About 1,000 schools have signed up so far.)

“Bark for Schools is the real deal,” Thad Schulz, technology coordinator at Sebeka Public School, said in a statement. “We didn’t have any sort of content scanning before getting Bark. Within a few days, Bark found multiple issues that would have otherwise gone unnoticed. When an issue arose that could have been life-threatening for one of our students, a Bark team member called our school to help us take action.”

Bark claims that it has helped save 33 students from imminent suicide and abort 12 school bomb and shooting threats.

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