Labor and civil rights groups are pressing a federal appeals court to revive a gender discrimination class action of more than 8,000 current and former Microsoft Corp. female employees, arguing a trial judge's ruling, left unchecked, will create hurdles for women suing to challenge workplace disparities.

The advocates filed an amicus brief in the U.S. Court of Appeals for the Ninth Circuit in support of the plaintiffs, who are challenging a Seattle federal judge's refusal to certify a class of Microsoft engineers and IT operations professionals.

The challengers are represented by the firms Lieff Cabraser Heimann & Bernstein; Outten & Golden; and Frank Freed Subit & Thomas. Last month, they filed papers in the Ninth Circuit challenging the denial of class certification. U.S. District Judge James Robart in June said no uniform policy and job descriptions tied together the thousands of women across multiple states to satisfy the class.

A coalition of 32 groups, including the National Employment Law Project, National Women's Law Center, ACLU, Lambda Legal Defense and Education Fund, filed the amicus brief last week. Jocelyn Larkin of the nonprofit Impact Fund was counsel of record on the brief, which arrived at an early stage in the proceedings. There has been no ruling on the merits of the Microsoft employees' claims of gender discrimination.

The brief challenges how Robart handled litigation declarations, arguing that the judge “erected an arbitrary numerical threshold” for such anecdotal evidence.

“Women may also be reluctant to accuse their managers of sexism where the biased judgments that have inhibited their advancement are subtle or undocumented. This reticence will be particularly acute in industries, like tech, where women have traditionally been underrepresented,” Larkin wrote in the brief.

A Microsoft representative said in an email, “After three years of litigation, the plaintiffs failed to show any legitimate basis for why this should be a class action. The judge's decision carefully and thoroughly applied the law and leaves no question that his decision was correct.”

The lawsuit against Microsoft was filed in 2012 and is one of several gender bias cases that targeted the technology industry. Other companies that have faced scrutiny include Google Inc., Oracle Corp., Twitter and Uber Technologies.

In the span of two weeks, judges in the Microsoft and Twitter cases denied motions to certify the classes. Robart and the California state judge in the Twiter case both found no common employment practice or standard contributed to pay disparities. Both judges drew on the 2011 U.S. Supreme Court decision Walmart v. Dukes, which created a more rigid standard to certify a class.

Microsoft's lawyers at Orrick, Herrington & Sutcliffe contend the class certification order was correctly decided and does not prove a “death knell” for the plaintiffs lawsuit. Orrick's Lynne Hermle, lead counsel for Microsoft, argued the “68-page opinion carefully applied the case law” to the allegations and determined that none of the “shifting theories of liability” satisfied class certification requirements.

Robart ruled that the anecdotal evidence in the case was not enough to demonstrate that Microsoft operated under a general policy of discrimination across 41 states and of workers holding thousands of unique positions.

The amicus brief principally argued that Robart applied a “mechanical, mathematical standard” in evaluating anecdotal evidence presented to the court. It argued that the declarations from the workers and the evidence of hundreds of internal complaints of gender bias should be convincing.

“Class actions allow women to challenge systemic gender discrimination without suing their employer individually and thereby putting their careers and workplace relationships in jeopardy,” the amicus brief argued. “This court should ensure that the requirements for bringing such cases are not set arbitrarily and unrealistically high, undermining their important purpose.”

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