Costco Wholesale Corp. ignored internal warnings that female workers couldn't get promoted, and Chief Executive Jim Sinegal opposed recommendations to post notices for all management positions, employees suing the company claim.

Court filings in a gender bias case against Costco show that members of a 2001 team investigating workplace barriers for women and minorities said company practices “allow for favoritism and individual biases in promotions.  The team recommended posting all management jobs.  Costco didn't follow the suggestion, John Matthews, vice president of human resources, testified in a March 2006 deposition, the Aug. 28 filings show.

The workers' lawyers said the filings bolster their claims that there was a pattern of discrimination against women at Costco. 

"They âre vulnerable to the argument that the red flags were raised and they ignored them," said Cyrus Mehri, who represents workers in lawsuits and isn't involved in the Costco litigation. "This shows reckless indifference to the rights of workers."

In the lawsuit, filed in 2004 by one current and two former Costco employees, workers claim women are prevented from applying for higher-paying management positions because the company doesn't post or advertise positions when they become available.  The suit is seeking back pay, future pay and punitive damages for up to 700 employees and a court order to change the policy.