About 90 employees work at a tech contractor for Google in the area called HCL, according to the statement, and 66 percent have signed union cards, indicating support for the plan. The employees are looking to unionize with United Steelworkers, an organization that represents about 850,000 workers. The Pittsburgh Association of Tech Professionals, a project from the union, has filed a petition with the National Labor Relations Board for a vote on the effort.

Google’s treatment of its contract workforce has been an issue of controversy in the past year. The company relies on a massive…