Two events are worth keeping in mind regarding US antitrust merger reviews as we head into Q4: (1) the federal government shutdown, which is affecting Hart-Scott-Rodino (HSR) reviews at the Federal Trade Commission (FTC) and Department of Justice (DOJ), and (2) newly effective state “Mini‑HSR” notice requirements in Washington and Colorado (with more states likely following). Below, we lead with the shutdown and then cover year‑end filing calendars before turning to the new state‑level rules.
October 7, 2025
