To have sex or casual relations with someone you work with. The
consequences are risky; that you will be caught with 'company fish' or
potentially loose your job, or just be stuck working in an
awkward situation.... but you do it anyway.
"Damn, that boy is hot! Ima hit him up at the staff party!"
"Yeah he is, but I never
fish off the company pier. After
the last guy, we had a crazy fight in the lunch room later. I learned my lesson!"