UPDATED with details: 20th Television Animation has agreed to voluntarily recognize the Animation Guild as the collective bargaining representative of production workers employed on The Simpsons, Family Guy and American Dad! According to the guild, an arbitrator will be conducting a formal card count to certify the results this week.

The move to unionize came on May 26 when a super-majority of the shows’ production workers requested that the companies voluntarily recognize the guild as their bargaining agent. The guild then filed petitions for union elections with the National Labor Relations Board for each show.

Workers in the bargaining units include the shows’ production managers, production supervisors, production coordinators, writers’ assistants, production assistants, associate producers, office assistants and IT supervisors. The shows’ animators are already covered by the guild’s contract.

The news comes the same day that members of the Animation Guild voted overwhelming to ratify their new film and TV contract with the Alliance of Motion Picture and Television Producer.