Maintaining trade secrets, from company employees

The yahoo story Chiefs employees live in environment of ‘secrecy, intimidation, and fear’ included the text:

Staff members with office windows facing the team's practice fields were directed to keep the shades in their offices drawn, and security guards would interrupt phone calls if necessary to tell employees to close those shades. This applied to team president Mark Donovan as well — he told Babb that he kept his shades drawn in an effort to let employees know that one was not more trusted than others.