The RESTART SUNSET Act of 2025 amends chapter 6 of title 5, United States Code, to strengthen requirements for the periodic review of federal agency rules. It mandates that agencies conduct a comprehensive review of all existing rules within ten years of the Act's enactment, and new rules within ten years of their final publication. A key provision requires agencies to annually publish in the Federal Register a list of rules that do not have a significant economic impact on a substantial number of small entities, along with the justification for this determination. This aims to increase transparency regarding the regulatory burden on small businesses. Furthermore, the bill introduces a significant enforcement mechanism: if a court finds that an agency has failed to comply with these periodic review obligations for a specific rule, the court shall order the prohibition of that rule's enforcement . This provision provides a powerful incentive for agencies to adhere to the new review standards, ensuring rules are regularly evaluated for their ongoing necessity and impact.