The FBI is linking a hacker only known by the moniker "mr. grey" to a whopping 1.2 billion stolen internet credentials after finding his Russian email address in the evidence it gathered. It's unclear if he obtained all those by himself, though, or if he's even just a single person or a group of people operating under one name. Either way, if there were a contest for hackers, mr. grey would've won it by now, as this is apparently the biggest collection of stolen log-in details the FBI has investigated thus far. Reuters says that info came from the court documents the feds submitted to support its search warrant request in 2014. The authorities got their tip from cybersecurity firm Hold Security, which found out that a Russian hacking group called CyberVor has stolen 1.2 billion log-in details and over 500 million email addresses.