The United States' National Labor Relations Board has given staff at Activision Blizzard's Raven Software studio the green light for a union vote.

As reported by the Washington Post, the body ruled that the 21 quality assurance workers at the developer could take part in a union election. This comes in the wake of Raven Software staff announcing in January their intention to form the Game Workers Alliance union, with parent firm Activision Blizzard missing the deadline to recognise this organisation.

“While we respect the NLRB process, we are disappointed that a decision that could significantly impact the future of our entire studio will be made by fewer than 10 per cent of our employees,” Activision Blizzard spokesperson Rich George said.

“We believe a direct relationship with team members is the best path to achieving individual and company goals."

The NLRB is now posting ballots to employees at Raven. Activision Blizzard has said that it is reviewing further legal options and might even appeal the NLRB's decision.