How do you tell Theranos from not-Theranos before you'd invested a bunch of money in them? As far as we know there were quite a few large players in the indust

How do you tell Theranos from not-Theranos before you'd invested a bunch of money in them? As far as we know there were quite a few large players in the industry who were uninterested in Theranos - which means they have rejected their ideas before the ideas came into living.