Harvard student Aran Khanna was supposed to begin a summer internship with Facebook when he had the position abruptly taken away from him in May. Why? Because he created a Google Chrome browser extension that highlighted a major privacy flaw on the site.

The student’s tool, Marauder’s Map, allowed users to see the geolocation of other users they communicated with on Facebook Messenger. Facebook didn’t take kindly to the tool, first asking him to take it down, then stripping him of his internship. At first, the site said he scraped user data from the site, but when Khanna said all of the information was publicly available, they told him that he had “misused” the information. Now Khanna has fired back at the site in a highly public way: with a column in TIME Magazine.

“So much of our lives have shifted online so quickly that it is not always clear how much data we are making accessible to others,” he wrote. “Moving forward, will companies like Facebook be more aware of privacy concerns and more proactive in patching them? Or must we continue to rely on privacy guardians affecting change from the outside?”

Though a Facebook spokesperson told Business Insider that Khanna did not lose his internship because of the exposed privacy flaw, from an outside perspective it certainly seems as if that’s the case. But there is a silver lining: Facebook did fix the loophole, and users must now opt in to location sharing on Messenger.