U.S. Steel (X.US) and Nippon Steel have filed a lawsuit to challenge the acquisition barriers.

U.S. Steel Corp. (X.US) and Nippon Steel Corp. have launched two legal actions, aimed at challenging and rectifying the ongoing illegal hindrances faced by Nippon Steel in its proposed acquisition of U.S. Steel Corp.

Specifically, the first lawsuit has been filed with the U.S. Court of Appeals for the District of Columbia Circuit, alleging that President Biden's blocking order not only violates the principles of due process and the rule of law enshrined in the Constitution but also is tainted by improper political considerations. The lawsuit seeks to have the court vacate the review process of the Committee on Foreign Investment in the United States (CFIUS) and Biden's specific actions.

Following suit, the second lawsuit was filed in the U.S. District Court for the Western District of Pennsylvania, directly naming Lorenzo Gonzalez, CEO of Cleveland-Cliffs (CLF.US), the parent company of Cleveland-Cliffs, and David McCall, president of the United Steelworkers union, alleging illegal collusion among them to jointly hinder the strategic acquisition.

The legal actions were sparked by the sharp decline in U.S. Steel Corp.'s stock price on Friday, which fell 6.5%, amid a deadlock in federal regulatory approval of the merger, which coincided with Biden's reiteration of the importance of a strong domestic steel industry as a national security priority, further exacerbating market uncertainty.

As of writing, U.S. Steel Corp.'s stock price rose significantly by 3.51% before the market opened on Monday.