Former SpaceX engineer Ashley Foltz filed the proposed class action in California state court on Tuesday, saying the company paid her $92,000 per year while men with similar duties and qualifications were paid up to $115,000.

California law prohibits employers from paying workers less than colleagues who perform "substantially similar work" based on their sex, race or ethnicity.

Foltz said she discovered the discrepancy when SpaceX posted job openings for engineering positions with a salary range of $95,000 to $115,000. A California "pay transparency" law took effect this year requiring employers to post salary ranges in job listings.

SpaceX raised Foltz's pay to $95,000 only after it was required to include the information in job posts, according to the complaint.

Foltz alleges that SpaceX hires women and minorities into lower-level positions in order to justify lower salaries and promotes men and white employees at a greater rate than other workers, exacerbating the disparity in pay.

SpaceX did not immediately respond to a request for comment.

The lawsuit is the latest to accuse companies owned or run by Musk of employment discrimination.

The U.S. Department of Justice filed a complaint in August accusing SpaceX of refusing to hire refugees and asylees who lack U.S. citizenship. SpaceX has denied wrongdoing and last month filed a counter-suit seeking to block the government's case.

Tesla Inc (TSLA.O), where Musk is CEO, has repeatedly been accused by workers and government agencies of failing to stop racial and sexual harassment at its Fremont, California electric vehicle plant and other facilities.

And X Corp, formerly known as Twitter, is facing a series of lawsuits claiming it discriminated against women, older workers and employees with disabilities when Musk acquired the company last year and laid off half its workforce.

Tesla and X have denied wrongdoing.