A united states federal judge has ordered the immediate freeze of a multibillion-dollar merger between two tech giants, citing antitrust concerns that could reshape the digital advertising market. The ruling, filed late Tuesday, blocks the deal that would have created a monopoly controlling over 70% of consumer data flows, sending shockwaves through Wall Street and triggering a 12% drop in shares of the acquirer. Compliance teams now face a 90-day window to restructure or face permanent injunction, a move analysts call the most aggressive antitrust action in a decade from a united states federal judge.