Yes, as I said there are good arguments for allowing insider trading at least in some circumstances (and some arguments against). Until fairly recently, there

Yes, as I said there are good arguments for allowing insider trading at least in some circumstances (and some arguments against). Until fairly recently, there was no rule against insider trading in commodities in the US, and the market worked just fine. My point in my earlier comment was that your question about 'why?' seemed a bit weird. You can look up the 'why?' relatively easily, even if you don't find it convincing.