Every public company depends to some extent on the trust of its investors.

Volatility may be rising simply because investors must digest more information every day.

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.

For value investors, General Motors is a tempting target. The company's share of the North American auto market has steadily declined for two decades, and analysts say the company suffers from weak management and unexciting cars.

As a public servant, William H. Webster has an impeccable resume.

Because Genentech is a leading developer of cancer therapies, some doctors also fear that the company's pricing plans for Avastin - around $8,800 a month - may encourage other companies to charge more for their own oncology drugs.