In 2009, Twitter Inc. had hundreds of pages of confidential plans exposed after a hacker accessed the Gmail account of an employee by resetting the employee's password.

WSJ: What's a Company's Biggest Security Risk? You.

For instance, when every message from a sender's account is tagged with "privileged and confidential, " it might make it difficult to convince a judge that any one email is more private than another.

WSJ: Email Disclaimers Proliferate

The U.S. attorney said Chilowitz sent the confidential list and data from a Morgan Stanley computer to his personal AOL account and had communications from his Morgan Stanley e-mail to that unnamed "co-conspirator, " who worked at an unidentified consulting company that helped negotiate prime broker rates for hedge funds.

FORBES: Magazine Article