A judge ruled that a lawsuit against Cleveland Cliffs and the head of the United Steelworkers union can continue.
The suit was filed by U.S. Steel and Nippon Steel, alleging that Cliffs and the union leader tried to block their deal.
Judge Marilyn Horan decided that the suit would need amended if the steel companies wanted to proceed. However, she also urged all parties to try and find common ground.
The $14.9 billion merger between U.S. Steel and Nippon Steel was approved by the federal government earlier this year.