As long as there isn’t any tangible proof of a violation of the rules, you shouldn’t tell anyone about it. That will only create uncertainty.If you “only” have doubts, it’s up to you to decide how to deal with the situation. Remember: Every colleague has many duties and responsibilities and it’s better if you solve problems on your own.Even if you “only” doubt whether an action is moral, you should take the initiative: Ask colleagues what they think of the situation. Or contact your superior and speak up about the problem.