A federal appellate court has taken up an appeal of a decision denying class certification to thousands of women employed in technical positions at Microsoft who claimed they were systematically passed over for promotions and raises.

The U.S. Court of Appeals for the Ninth Circuit took up an intermediate appeal of the ruling denying class certification in the gender discrimination case Thursday. The Ninth Circuit will review a June decision by U.S. District Judge James Robart of the Western District of Washington who found there were no uniform policies or job descriptions that tied together the thousands of women across multiple states who were part of the proposed class.

A Microsoft spokesman said in a statement that the company continues to believe “that the judge made the right decision in denying class certification.”

“There is no bias in Microsoft's pay and promotion practices,” the spokesman said. “We remain committed to increasing diversity and making sure that Microsoft continues to be a workplace where everyone has an equal opportunity to succeed.”

The company is represented by a team from Orrick, Herrington & Sutcliffe.

Plaintiffs in the case are represented by co-lead counsel at plaintiff-side employment law firm Outten & Golden and national class action firm Lieff Cabraser Heimann & Bernstein.

Lieff Cabraser's Kelly Dermody said in a statement that “the evidence here demands that Microsoft's common discriminatory systems be addressed on a class basis so that women at the company can get justice.”

Plaintiffs' petition for permission to appeal the district court's class certification ruling had the backing of more than 30 civil rights, labor and women's rights groups who filed an amicus brief.

The brief challenged the way Robart handled declarations from plaintiffs, claiming the judge “erected an arbitrary numerical threshold” for the necessary anecdotal evidence to push forward with class claims.

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

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