Insider trading is hard to prove. To be convicted, a person must have bought or sold a stock based on material information that is both unknown to the general public and likely to have had an important effect on a company's stock price.
Although not well known outside Wall Street, Freddie Mac and its corporate cousin, Fannie Mae, are two of the world's largest financial institutions and play a crucial role in the housing market.
The details of the personal expenses that executives put on the company tab often are not known because loopholes in federal disclosure rules let publicly traded companies generally avoid disclosing the perks they give executives along with pay and stock options.