Earlier quoted context omitted.
> it need only be information that is material and non-public. I think this is wrong as well. Suppose you are a independent technician repairing cars. Over time you notice, that, say BMW car quality used to be good but has gone to shit. That's not public information, but you would be allowed to short BMW stock in the hopes that, once public catches on, their share price will tank. In fact half the point of stock trad…
>I think this is wrong as well. The gp's wording is a little confusing but he's just trying to explain the transitive logic of non-public information transferring from a "true insider" to an outsider is also "insider trading" and thus illegal. Think of it as the provenance of information coming from an insider. E.g. Martha Stewart is an "outsider" and not an insider of drug company ImClone but she was found guilty of…
I was trying to avoid the use of "insider," because people tend to assume that means employees or directors, but that is not the case. Outside organizations who have, as an example, signed an NDA with the organization may learn of material non-public information, and trading on that could constitute insider trading.