You are implying that I don't realize that insider trading reveals extra information. But I have clearly stated in almost every post that insider trading would reveal additional information. There's no point continuing this discussion if I am responding to what you say but you're ignoring what I say. I'd ask you to keep an open mind and not assume that other people just need to be enlightened via terse replies.

>So (and again, a model is really needed to confirm this) public information is cheaper in terms of its impact on liquidity, than insider information. One thing I'm not certain of is whether many insiders competing to trade on the same information would be as good as public information

That sounded to me like you were against insider trading because it wasn't as efficient as public information. I don't get why that implies we shouldn't allow insider trading.

Your other post said that it necessarily harms someone, but I think that argument was successfully argued against in the link I posted above. Do you have a problem with that part of it?

Also, I would still like it being up to the company. If liquidity is important to them, and the experiment shows that allowing it leads to less liquidity, then eventually they'll stop it.

I don't think that market is inefficient enough to necessitate government action.