Yahoo revealed in September 2016 that the personal data of over 500 million users had been stolen by hackers in 2014. Yahoo didn’t go public about the breach until December 2016, advising users to be cautious of unsolicited communications and to ensure that they were not using the same passwords and security questions/answers on any other online accounts. The timing for the company couldnt have been worse, as it was in the process of trying to sell itself to Verizon. But it was hard to feel too sorry for Yahoo as some of its staff had known since 2014 that its systems had been compromised by what it believed to be a state-sponsored attacker”]