Today only a handful of big firms have the sort of board that seems hand-picked to be loyal to the boss, chief among them being News Corporation, says Paul Hodgson of GMI, a corporate-governance ratings firm.

ECONOMIST: How can you tell a good board of directors from a bad one?

While the moves are legal and disclosed in regulatory filings, "there are certainly some fairly serious red flags in terms of behavior that are raised there, " said Paul Hodgson, chief research analyst for GMI Ratings, a corporate-governance and risk-management research firm.

WSJ: Ocwen's Rapid Growth Puts Spotlight on Its Practices

To identify the most transparent and trustworthy businesses that trade on American exchanges, Forbes turned to GMI Ratings (GMI), a pioneer in the application of non-traditional risk measures for financial analysis.

FORBES: America's 100 Most Trustworthy Companies

Once the pool is culled to a few hundred companies, Ethisphere cross-checks it against governance lists from organizations including GMI Ratings and FTSE4Good.

FORBES: The World's Most Ethical Companies