Hard to say what the investigation is about, maybe some disgruntled investors who bought the stock at the IPO offering price and has gone down hill every since and think they were robbed?
Talks about Petrobras not paying for the 225īs to all the operators in Brazil when they were stopped but that was resolved some time ago, aircraft are flying and getting paid. Or at least I think they are with all the problems with Petrobras these days if they can pay there bills or not.