Apple has rehired security expert Jon Callas (pictured), who left the firm to work at companies including PGP Corp, Blackphone and Silent Circle, in a move that seems to be a reaction to its recent legal battles with the FBI.
Callas admitted that he was parting company with Silent Circle last month with a message on Twitter, although he did not reveal where he was going.
Last week was my last day-2-day w/ @SilentCircle. Yes, amicable. As an investor, I love the enterprise direction. Just going a different way— Jon Callas (@joncallas) April 2, 2016
His LinkedIn profile gives nothing away directly, merely stating that he is in 'Personal Stealth Mode', adding: "I'm not interested it talking about it. But I'm doing it, and I like it."
Whether this is a reference to his work at Apple is not clear, but an Apple spokesperson confirmed the Callas appointment to Reuters, saying that he joined in May, so it could well be.
Callas worked for Apple in the 1990s as a senior scientist, as listed on his LinkedIn profile.
Apple did not reply to a request for comment on the role, although it's certain that it relates to encryption and privacy given Callas's background and Apple's efforts to protect the data on its devices, even from the US government.
CEO Tim Cook said a lot about the importance of encryption and security recently after a protracted and very public legal battle against the FBI over whether Apple should help to unlock an encrypted iPhone.
"To protect people who use any products, you have to encrypt. You can just look around and see all the data breaches going on," he once said in opposition to UK surveillance plans.
"These things are becoming more frequent. They can not only result in privacy breaches but in security issues. We believe very strongly in end-to-end encryption and no back doors."
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