he's pointing out the technical definitions of the terms; you're insisting on the imprecise/wrong popular usage.

"insider trading", when insiders trade, say the CEO sells his stock bonus, is regulated (has to announce in advance, follow a plan) but completely legal. Some investors track how much insiders are trading in order to judge confidence in a stock.

"trading on inside information" (whether you are an insider or not) is not legal.

I may have been ambiguous but I am saying if you work somewhere (pre IPO) and you can see their killing it, on fire, and are seeing a truth other companies can't see then you know (perhaps doing some more research on public info) that it is a good buy.

Also for private companies you often get an all hands with financials, sales info, strategy etc.

The bet here is: this company isn't just lucky they have a killer system. You would get shares privately if possible. Even at IPO at a higher price, knowing they are kickass you can buy then.