The way it works in the real world is that all insider trades are done publicly.  I think they're also supposed to be announced in advance in order to make sure that they're not using insider information about upcoming announcements  (i.e. Tim Cook isn't allowed to schedule his share purchases right before they announced the iPhone 6)

Unfortunately, the SEC is actually pretty lazy about enforcing rules.  Normally, people just get away with a fine or some bullshit. But the threat is enough to prevent people from just randomly spouting bullshit.