Would you pay $100 a year to keep Facebook from selling your data? That’s the proposal from a Dartmouth researcher who says Facebook’s current security fixes are “not going to cut it.”

In a statement posted Wednesday, CEO Mark Zuckerberg acknowledged the social network had made “mistakes” with users’ privacy that allowed data firm Cambridge Analytica to collect information on 50 million unsuspecting users.

Zuckerberg said that “the most important actions to prevent this from happening again today we have already taken years ago,” and that “this specific issue involving Cambridge Analytica should no longer happen with new apps today.” 

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But, he said, “there’s more to do, and we need to step up and do it.”

Zuckerberg plans audits of “suspicious activity” from apps and reports on the misuse of user data.

But Dr. Luke Stark, an online privacy researcher at Dartmouth University, says those fixes don’t go far enough — because “the problem is Facebook itself is collecting all this data.”

To safeguard users, Dr. Stark proposed Facebook “build a subscription model, where they say ‘We’re going to charge you $100 a year for the website, and for that money we’re not going to sell your data.'”

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Stark immediately added that that is “not what Facebook’s going to do, because Facebook’s business model is so strongly tied to a broad collection of data.” And it’s true — Facebook rakes in billions of ad dollars — about $6 per user each quarter — precisely because of its mountain of personal information.  But whether that revenue model is sustainable is something that needs to be considered.

“The worst thing that could ever happen to Facebook is that it becomes cool to delete your account,” professor Karen North, director of USC Annenberg’s Digital Social Media Program, told TheWrap. Unfortunately, that worst case scenario could be taking shape, with the #DeleteFacebook momentum picking up in the wake of Cambridge Analytica.

But Facebook’s popularity was already waning before by the data-collection scandal broke, with the company losing around a million daily users in the U.S. last quarter.