How Google Almost Killed ProtonMail
By the summer of 2015, ProtonMail passed half a million users and was the world’s most well known secure email service. ProtonMail was also ranking well in Google search at this time, on the first or second page of most queries including “encrypted email” and “secure email”. However, by the end of October 2015, the situation had changed dramatically, and ProtonMail was mysteriously no longer showing up for searches of our two main keywords.
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In November 2015, we became aware of the problem and consulted a number of well known SEO experts. None of them could explain the issue, especially since ProtonMail has never used any blackhat SEO tactics, nor did we observe any used against us. Mysteriously, the issue was entirely limited to Google, as this anomaly was not seen on any other search engine.
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In August, with no other options, we turned to Twitter to press our case. This time though, we finally got a response, thanks in large part to the hundreds of ProtonMail users who drew attention to the issue and made it impossible to ignore. After a few days, Google informed us that they had “fixed something” without providing further details. The results could be immediately seen.
Update (2016-11-12): See also: Hacker News.