Discussing whether one Bitcoin-related company is fake or not may not really be possible here because you are not giving us any other details on those companies you are talking about. When you say Bitcoin company you must be referring to a company whose business has something to do with Bitcoin like a trading company offering its service to customers promising that they would be sharing their gains with the members, right?

Now, whether one is involved with Bitcoin or not, examining one company can entail a lot of time and resources. You must be a good investigator to be able to arrive at a certain conclusion. But there is an easy way out of this dilemma: Just remember that when they offer something to good to be there is a strong chance that it is really a lie! Of course, there can be an exemption here but it only one out of a thousand cases.

Beware of those Bitcoin-engaged companies promising you heaven here on Earth because they are just actually bringing you to hell.