LinkedIn announced Friday that its now offering two-factor authentication (2FA) The social networking site got savagely hacked on 5 June 2012. Cybercrooks stole about 6.5 million passwords, over 60% of which were cracked within the span of one measly day. LinkedIn is now giving users the option of using something stronger than a password and user name to protect their accounts. LinkedIn sends the code to users phones via SMS, which is more difficult for attackers to breach your account.”]
Source: https://nakedsecurity.sophos.com/2013/06/04/linkedin-two-factor-authentication/