KKR’s agreement to pay a reported $250 million to resolve U.S. Department of Justice allegations over repeated violations of federal premerger filing rules is a striking escalation in Hart-Scott-Rodino enforcement. For dealmakers and their counsel, the settlement is more than a large penalty: it is a clear warning that the government is prepared to pursue aggressive remedies when it believes parties have sidestepped antitrust review.

The dispute centers on the HSR Act, which requires parties to certain acquisitions and mergers to notify federal antitrust regulators and observe a waiting period before closing.