The other anomaly that occurs is a sudden dip in the share price if the forthcoming news is going to be bad.
I doubt many of the trades get audited. Who's got the time or the budget to look up family trees and facebook friends of all those trades and see if each 'entity' trading (if that can easily be established) has a relationship with an employee of the company or the company's auditor, board, publisher etc? Proving anything is time consuming and lengthy with no guarantee of success.
The only way to hit the limelight with the authorities is to be directly involved with the business in question and trade in high volumes over a short timeframe just before a big announcement. Everything else goes under the radar I believe. How can it not?
I wrote a bit of a rant about this when NPX blipped.
http://www.sharetrader.co.nz/showthr...ht=#post392317
Probably more of a topic in the off-market discussions forum. 12 hours 20 minutes (plus race time) before McLaren pulls off a win for Ryman!