It's been a bad week for Silicon Valley's "boys' club." Both Facebook and Twitter are being sued for sexism, and Ellen Pao's high-profile gender discrimination case against venture capital giant Kleiner Perkins was given the green light by a judge.

Twitter is facing a class action suit that claims the company's promotion policy heavily favors men, and a Facebook employee is suing over sexual discrimination and sexual harassment, among other offenses.

Tina Huang, who worked for Twitter from 2009 through 2014 in varying software roles, filed a class action suit against her former employer in San Francisco on March 19. Huang says she was overlooked for promotion because of her gender and then ultimately fired when she complained.

The lawsuit states that a largely male management is responsible for promotions, and that results in a bias favoring men — whether intentional or not. Huang missed out on a promotion to a senior engineering role and claims that after complaining directly to CEO Dick Costolo, she was put on administrative leave and forced out of the company.

Huang is attempting to bring a class action suit on behalf of current and former female employees of Twitter. The suits argues that "the company's promotion system creates a glass ceiling for women that cannot be explained or justified by any reasonable business purpose."

The suit claims that rather than openly posting job opportunities, only certain Twitter employees learn of promotions through an informal "shoulder tap" process, which favors the "boys' club." 

On March 21, another high-profile Silicon Valley sexism case was given clearance. Ellen Pao is seeking punitive damages for gender discrimination against her former employer, Kleiner Perkins. Pao is looking for $16 million in lost wages and bonuses and is also pursuing unspecified punitive damages.

Perkins tried to have the unspecified damages thrown out, but a San Francisco judge has denied the request, which means that tens of millions of dollars could be added to any potential damages awarded.

In a similar situation to Huang, Pao claims she was passed over for promotion in 2012 and then fired when she objected.

Pao's lawyer is also involved in a sexual discrimination case against Facebook. Former employee Chia Hong, who was fired in 2013, is suing Facebook for sex discrimination, sex harassment, race discrimination and intentional infliction of emotional distress, among other allegations. Hong claims she was discriminated against for being female and Taiwanese and was replaced by a less qualified, less experienced man.

Hong is also suing Anil Wilson, director of finance and infrastructure tools at Facebook, as well as a number of other unnamed male employees. The suit says Wilson routinely discriminated against Hong, asking her to serve drinks to male employees and telling her she should stay at home and watch her kids. The suit was filed in San Mateo Superior Court on Feb. 15.

None is this is good news for an industry trying to attract more female employees and rid itself of a "boys only" image. Cases like these are bound to continue as long as the industry is dominated by mostly white male employees, as shown in this 2014 survey.