NEWARK, N.J.—Two female sales representatives have filed a putative class action lawsuit seeking $100 million in damages that alleges a medical testing firm engaged in a pattern of gender discrimination against its female employees.

The suit against Madison, N.J.-based Quest Diagnostics Inc. and subsidiary AmeriPath Inc. was filed Thursday in federal court in Newark, N.J., on behalf of Erin Beery, an executive territory manager in Indianapolis and with the firm since 2004, and Heather Traeger, senior executive territory manager in Bradenton, Fla., with the firm since 2005.

According to the lawsuit, women who work at Quest say “high-ranking company officials within the predominantly male management team foster an environment hostile to the success and advancement of female employees. Promoting ‘old boys' club' attitudes, upper management regularly grooms junior male employees for leadership by granting them disproportionate access to resources and exposure to decision-makers.”

The lawsuit was filed by New York-based law firm Sanford Wittels & Heisler L.L.P., which represented plaintiffs in litigation that led to Novartis A.G. agreeing in 2010 to pay $175 million to settle a class action that had accused the Swiss pharmaceutical firm of unfair treatment of 5,600 female sales reps regarding pay and promotion.

The Quest Diagnostics lawsuit says that only four of the 17 top management members of the company are female.

“When female employees complain to upper-level management about discrimination, managers refuse to investigate these claims as required by law, instead telling these women, ‘You are lying!' When female employees receive unfair performance reviews, instead of their concerns being addressed, they have been asked, ‘Are you just going to go ahead and quit?' Women who wish to challenge discrimination are faced with an indifferent Human Resources Department that routinely fails to respond appropriately” to complaints of gender discrimination, sexual harassment and retaliation, according to the suit.

On behalf of Quest's female employees, the lawsuit accuses the company of pay, promotion and pregnancy and family responsibilities discrimination under Title VII of the Civil Rights Act of 1964 and with violation of the Fair Labor Standards Act.

On behalf of Ms. Beer and Ms. Traeger alone, the suit also alleges retaliation and sexual harassment under Title VII.

“Quest Diagnostics is an equal opportunity employer,” a spokeswoman for the company said in an email. “We are proud to be routinely recognized as a top employer in communities around the U.S.”