A class action filed Thursday against Google Inc. claims the tech company systemically pays women less than men in similar jobs and also enables unequal promotions and opportunities for male and female workers.

The sex discrimination case filed in San Francisco Superior Court, Ellis v. Google, accuses the Mountain View, California, company of paying women at all levels less than men in comparable positions, assigning women lower-tier jobs with lower pay and compensation than men and promoting women less frequently. The lawsuit also claims Google failed to correct these issues even after being made aware of them.

“While Google has been an industry-leading tech innovator, its treatment of female employees has not entered the 21st century,” said Kelly Dermody of Lieff Cabraser Heimann & Bernstein, who was among the lawyers who filed the case. “This case seeks to ensure fairness for women at Google.”