Dropbox – Jul 01, 2012
On Jul 01, 2012 attack happened. Dropbox suffered a data breach which exposed the stored credentials of tens of millions of their customers. In August 2016, they forced password resets for customers they believed may be at risk. A large volume of data totalling over 68 million records was subsequently traded online and included email addresses and salted hashes of passwords (half of them SHA1, half of them bcrypt). On Aug 31, 2016 only breach discovered.