The only time I suspected something was wrong (beyond Mark himself) was in April 2013 when my ex-employee contacted me to report there was an account that seemed to be buying bitcoins at a surplus rate, and it seemed to be internal to the company.
It's even worse than I thought. The fake trading started in April.
Read it again. Ex-employee contacted him in April 2013, which means it started even earlier than that.
All considered, it's pretty good that we're maintaining above $200