This market will resolve to "Yes" if the U.S. Public Health Service officially withdraws or ends its recommendation for adding fluoride to U.S. drinking water, or if the recommended fluoride level is changed to 0.0 mg/L between September 23 and December 31, 2025, 11:59 PM ET (see: https://www.cdc.gov/fluoridation/about/community-water-fluoridation-recommendations.html). If responsibility for directives on fluoride is transferred from the U.S. Public Health Service to another federal agency, any qualifying announcement from that new agency will qualify. The resolution source will be official information from the U.S. Government.