How to track insider trading?

How do you track insider trading? How do you know if an employee of that company buys shares of their own company?

You are allowed to own shares in the company you work for. A number of executives will do so. Insider trading is using privileged knowledge of the company in order to benefit financially. You don't even need to be associated to the company to be involved in insider trading (just get access to knowledge that the public does not have and act on it).

On the ASX each company's announcements will have Director's changes of holdings, if any.
Other announcements such as change in substantial holding, or, becoming a substantial holder could also be considered as insider trading under certain circumstances.
It probably should be stated, that I think the term insider trading is based on illegally profiteering from insider knowledge, but the term also is used for the general majority of legal trades by Directors or employees.

F.Rock
PS. No one likes to rat...