Four female workers in the USA are looking to sue Sanofi-Aventis for $300 million, after claiming that the firm has sexually discriminated against them in terms of pay and promotion.

An earlier version of the lawsuit was presented to a US District Court in New York in March by one employee and a revised complaint has been filed which includes new claims by three more plaintiffs. The women’s lawyers, Sanford, Wittels and Heisler noted that the potential class of plaintiffs could involve up to 7,000 current and former female sales staff at Sanofi, adding that “the essential allegations are that women are not paid the same amount as men and that women are not promoted at the same rate as men".

Plaintiff Karen Bellifemine, who worked for Sanofi for more than 12 years, alleges that the company “does not discipline managers or other employees when they discriminate against female employees or create a sexually charged and inhospitable workplace for women”. She also claims that sexually explicit language was used in e-mails and that she was twice denied promotions that were given to male colleagues.

A spokesman for Sanofi's US unit, Marc Greene, was quoted as saying that the company is "confident that the suit lacks merit and that all of our employees are treated fairly and in compliance with all applicable federal and state laws."

This case comes just a month after female plaintiffs, also represented by SWH, who brought a discrimination case against the US unit of Novartis were told by a judge in New York that their lawsuit, which is seeking damages of $200 million, can proceed as a class-action.