If I work at a company, I am bound to know things that are not public knowledge. This means that any trade I make is technically insider trading.
Example: I am an engineer, working on a new unannounced product which I think will do well. I buy shares of my company in advance of the release of that product. A few years later, after the product has shipped and delivered the expected gains, I sell my stock.
Will I go to jail for insider trading?