Relatives of passengers who died in Boeing Max crashes will tell a judge to throw out a plea agreement that they say is a sweetheart deal for Boeing.

Relatives of some of the 346 people who died in two crashes involving Boeing 737 Max planes are in court Friday, where their lawyers are asking a federal judge to throw out a plea agreement that the aircraft manufacturer struck with federal prosecutors.

Boeing filed a complaint with the NLRB accusing the IAM union of bargaining in bad faith, after negotiations collapsed this week.

The union violated its duty to bargain in good faith by engaging in regressive bargaining, surface bargaining, misrepresenting deal terms and negotiation status to its members and the public, and failing to bring representatives to the bargaining table with the authority to reach an agreement,

Boeing said late on Thursday it filed an unfair labor practice charge with the National Labor Relations Board against the union that represents about 33,000 striking U.S. West Coast factory workers. The planemaker said the International Association of Machinists and Aerospace Workers unit representing the workers had failed to bargain in good faith during the four-week work stoppage.