Every single Yahoo account that existed in August 2013 was affected by an epic hack.
http://money.cnn.com/2017/10/03/technology/business/yahoo-breach-3-billion-accounts/index.html
* three billion accounts * reported * Related: Who the Russian hackers targeted when they stole Yahoo emails * acquired * Related: The biggest data breaches ever * initially * Related: Former Equifax CEO testifies before Congress * hit by a hack * indicted * eported in December