Large investors are demanding more diversity in the boardroom, and most companies are heeding those calls. But a dozen of the largest companies in the U.S. have yet to add a single female director.
An analysis by executive compensation research firm Equilar and CNBC of companies on the Fortune 500 found that 12 companies have no women directors. The list, below, includes companies ranging from Icahn Enterprises, the holding company run by billionaire Carl Icahn, to Energy Transfer Equity, an oil and natural gas pipeline company.
CNBC sought comment from each of these companies, but as of publication, none had responded.
On Wednesday, the New York State Common Retirement Fund announced that it would plan to vote against all board directors standing for re-election at companies that have no women on their boards. In situations where a company has only one woman on the board, the state pension fund plans to vote against members of the governance committee.
"It is unconscionable that hundreds of publicly-held U.S. companies have no women directors," New York State Comptroller Thomas DiNapoli said in the statement today. "We're putting all-male boardrooms on notice — diversify your boards to improve your performance."

The fund currently holds shares in more than 400 public companies that have no women on their boards and 700 companies that have just one woman director.
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