Agencies Rescind “Harm” Definition

On July 14, 2026, the U.S. Fish and Wildlife Service (USFWS) and National Marine Fisheries Service (NMFS) (collectively, Services) published a final rule to rescind the definition of “harm” from their Endangered Species Act (ESA) implementing regulations (Final Rule). For decades, the Services’ definition of “harm”—which indicated that, under certain circumstances, modifying the habitat of ESA-listed species could result in prohibited “take”—has been the primary means by which the ESA impacts private activities. Following the effective date of the Final Rule on September 14, 2026, many activities that would have been regulated under the former definition may no longer be. For now, it remains unclear how the Services will administer the “take” prohibition of the ESA moving forward, and how federal courts will interpret the same.