Microsoft’s pledge to stay neutral in unionization efforts is about to be tested in a big way. On Monday, quality assurance staff at ZeniMax Media went public with the news that they’re working to form a union. The approximately 300 workers involved in the effort want to be represented by the Communications Workers of America (CWA). That’s the same union that recently helped QA staff at Raven Software and Blizzard Albany win their organization bids.

Microsoft did not immediately respond to Engadget’s comment request. A company spokesperson told The New York Times Microsoft was “committed to providing employees with an opportunity to freely and fairly make choices about their workplace representation,” adding the campaign was “an example of our labor principles in action.”

ZeniMax Media is the parent company of some of Microsoft’s most prized first-party studios, including Arkane, Bethesda and id Software. Microsoft paid $7.5 billion in an all-cash deal to acquire the publisher in 2020. A successful unionization bid would affect all the studios under the ZeniMax umbrella.

According to The Times, QA staff at ZeniMax began voting on unionization on December 2nd, the same day testers at Blizzard Albany voted 14 to 0 to join the CWA. Staff at the Microsoft subsidiary can share their stance on the matter by signing a union authorization card or by voting through an electronic portal. A decision is expected before the end of the month.

In June, Microsoft announced it would respect all unionization efforts at Activision Blizzard following the close of its $68.7 billion deal to buy the publisher. At the time, the company signed a landmark neutrality agreement with the Communications Workers of America. Antitrust regulators in the UK and EU are currently conducting investigations of Microsoft’s bid to buy Activision Blizzard.