On October 10, 2024, the Federal Trade Commission issued new final rules governing the US premerger notification filing process. These rules – the first major overhaul to the Hart-Scott-Rodino (HSR) filing form in the nearly 50-year history of the HSR Act – will fundamentally alter the premerger notification process. While the rules omit some of the more extreme aspects proposed in the 2023 draft rules, they impose substantially more burdens on filing parties than the current filing regime. The changes will have wide-ranging implications for all parties required to notify transactions under the HSR Act.