Calls by WellPoint (WLP) shareholders to oust CEO Angela Braly are growing louder, according to a report in the Los Angeles Times.

Criticism is intensifying about the second-largest U.S. health insurer’s poor stock performance, weak quarterly earnings and bleak outlook that includes a predicted loss of some 900,000 members.

Billionaire investor and Omega Advisors CEO Leon Cooperman has been one of the most outspoken stockholders against Braly, telling Bloomberg earlier this month that she is “the wrong CEO to lead the business.”

As of March, his Omega Advisors held 2.1 million shares of WellPoint, which adds up to a stake of about 1%. Other investors, including Orbimed Advisors, have blamed management missteps.

Last week, investor Royal Capital Management, which held some 837,000 shares of WellPoint as of the end of June, sent a letter to WellPoint urging Braly to step down, saying she “failed miserably” as CEO.

That had sparked a debate among who would rise as her replacement. WellPoint did not immediately respond to FOXbusiness.com for a comment on this story. 

Braly became CEO in 2007 and is one of just 20 women running Fortune 500 companies. Among other things, she has been criticized for her and the board’s approval of stock buybacks in recent years that have done little to improve the company’s stock price, as well as an increase in premiums by 10% or more on families and small businesses.

Down less than 1% on Tuesday, WellPoint shares have fallen 13% since January and more than 24% since the beginning of 2008.

The LA Times reported that shareholder complaints about Braly, who also serves as    WellPoint’s chairman, have grown louder since the insurer posted a 1.9% decline in commercial membership last month that caused earnings to fall to $643.6 million, or $1.94 a share, from $1.89 a year ago, below Wall Street’s consensus.

While sales had grown 2% for the period ended June 30, the company had to lower its fiscal 2012 guidance far below average analyst estimates.

Meanwhile, WellPoint is moving forward with its $4.9 billion purchase of rival Amerigroup, the costs of which WellPoint had named as one of the reasons why it had to lower its full-year outlook. Another main reason for the slashed guidance was an erosion of membership.

Last week, Morgan Stanley (MS) downgraded WellPoint to “equalweight” from “overweight,” citing ongoing price challenges.

The bank said WellPoint could face continued pressure from commercial health insurance prices and medical costs and said its risk-reward looks “less compelling” than its peers.

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