U.S. Labor Department is also investigating.
Three female former employees of Alphabet’s Google filed a lawsuit on Thursday accusing the tech company of discriminating against women in pay and promotions.
The plaintiffs are a former Google software engineer, a former communications specialist and a former manager who worked in various roles at the Mountain View, Calif.-based company. They claim Google pays women in California less than men who perform similar work, and assigns female workers jobs that are less likely to lead to promotions.
“While Google has been an industry-leading tech innovator, its treatment of female employees has not entered the 21st century,” Kelly Dermody, a lawyer for the women, said in a statement.
Google did not immediately respond to a request for comment.
The plaintiffs are seeking to represent a class of women who worked at Google in California over the last four years.
Google is facing a separate probe by the U.S. Department of Labor into its pay practices. The investigation stems from a 2015 audit in which the department says it discovered sex-based wage gaps among Google workers.
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The department last month appealed an administrative judge’s July decision that rejected its request for contact information for thousands of Google employees.