Federal Agencies Finalize Rescission of “Harm” Definition Under Endangered Species Act

On July 10, 2026, the U.S. Department of the Interior and the U.S. Department of Commerce jointly announced via press release the finalization of a rule rescinding the longstanding regulatory definitions of “harm” under Section 9 of the federal Endangered Species Act (ESA). The final rule, published today in the Federal Register, removes the definitions of “harm” from 50 C.F.R. § 17.3 (U.S. Fish and Wildlife Service) and 50 C.F.R. § 222.102 (National Marine Fisheries Service) and takes effect 60 days later, on September 14, 2026.

This alert follows our April 24, 2025 client alert (found here), which analyzed the proposed rulemaking and its potential implications for development projects. The final rule is consistent with the proposed rule: It eliminates the regulatory definitions of “harm” without adopting any replacement, thereby narrowing the scope of activities that may constitute prohibited “take” under the ESA. The rescission is one of the most significant changes to the ESA in decades and has significant potential implications for developers, energy and infrastructure project proponents, and landowners.

A coalition of conservation organizations has already announced plans to challenge the rescission in federal court. As such, project proponents should not assume immediate narrowing of incidental take permitting obligations until the rule takes effect and survives anticipated judicial challenges.

BACKGROUND AND PROCEDURAL HISTORY

The Prior “Harm” Definition

Since 1981 (for FWS) and 1999 (for NMFS), the Services’ regulatory definitions of “harm” have included “significant habitat modification or degradation where it actually kills or injures wildlife by significantly impairing essential behavioral patterns, including breeding, feeding, or sheltering.” This definition served as the primary mechanism by which habitat-disturbing activities (such as land grading, vegetation removal, streambed alteration, water operations, renewable energy development, telecommunications infrastructure, and transportation projects) triggered the need for incidental take permits (ITPs) under ESA Section 10 or incidental take statements under Section 7 consultation, even where there was no direct physical contact with or intentional targeting of individual listed species.

The definition was upheld by the U.S. Supreme Court under Chevron deference in Babbitt v. Sweet Home Chapter of Communities for a Great Oregon, 515 U.S. 687 (1995) (Sweet Home).

The Proposed Rule (April 2025)

As discussed in our prior alert, on April 17, 2025, FWS and NMFS published a Notice of Proposed Rulemaking (90 FR 16102) proposing to rescind the “harm” definitions in their entirety, without replacement. The Services relied on the Supreme Court’s decision in Loper Bright Enterprises v. Raimondo, 603 U.S. 369 (2024) (Loper Bright), which overruled Chevron deference, to argue that the regulatory definition of “harm” is not the single best reading of the statutory text, and cited Justice Scalia’s dissent in Sweet Home for the proposition that “harm” requires an affirmative act directed immediately and intentionally against a particular animal.

The comment period closed on May 19, 2025, generating an exceptionally high volume of 357,699 public comments (Docket FWS-HQ-ES-2025-0034-0001) — an unusual level of engagement for a technical regulatory action.

OIRA Review

On April 3, 2026, the final rule arrived at the White House Office of Information and Regulatory Affairs (OIRA) for review under Executive Order 12866, which requires OIRA review of significant regulatory actions prior to issuance. OIRA completed its review on July 7, 2026.

THE FINAL RULE

Substance of the Rescission

Consistent with the proposed rule, the Services have rescinded the regulatory definitions of “harm” from 50 C.F.R. § 17.3 (FWS) and 50 C.F.R. § 222.102 (NMFS) in their entirety. No replacement definition has been adopted. The final rule was published in the Federal Register on July 14, 2026 (91 Fed. Reg. 43300), and takes effect 60 days later, in mid-September.

The preamble to the final rule reiterates the Services’ position that the best interpretation of “harm” under ESA Section 3’s definition of “take” is that it requires “an affirmative act . . . directed immediately and intentionally against a particular animal,” rather than “an act or omission that indirectly and accidentally causes injury to a population of animals” (citing Sweet Home).

Agency Rationale

The agencies’ July 10, 2026 press release states the rescission will “reduce unnecessary permitting, cut compliance costs and eliminate confusion for landowners, small businesses, energy producers, farmers, ranchers and local governments.”

Interior Secretary Doug Burgum further stated:

“For years, federal agencies abused the ESA to obstruct lawful land use and burden American families and businesses. That approach turned routine activity into a regulatory trap, drove up costs that impacted people’s lives, and expanded federal authority beyond what Congress intended. This action restores common sense, respects private property, provides much-needed certainty for landowners and follows the statute Congress actually passed.”

The Services continue to rely on Loper Bright’s overruling of Chevron deference, arguing that Sweet Home’s holding (i.e., that the prior definition was a permissible construction of the statute) no longer compels the broader, habitat-based reading of “harm” now that courts must independently determine the best reading of the statute.

Prospective Application

Importantly, the rescission operates only prospectively. Existing incidental take permits and habitat conservation plans that were previously issued remain valid and enforceable. The rule does not affect the terms or conditions of permits already in place. Similarly, activities affecting habitat, if undertaken prior to the effective date of the recission without incidental take permit coverage, could still result in ESA violations and attendant enforcement liabilities.

Additionally, the rescission does not affect critical habitat designations or the Section 7 consultation process for federal actions. Federal agencies must still consult with the Services on actions that may affect listed species or designated critical habitat.

State Laws Unaffected

Although the federal rescission narrows the scope of the federal ESA’s take prohibition, state endangered species laws, including the California Endangered Species Act (CESA), are unaffected by the federal rescission. Under CESA, state authorization may still be required where habitat disturbance would result in take of a state-listed species, but CESA does not independently prohibit habitat modification in the absence of take.

PRACTICAL IMPLICATIONS FOR PROJECT PROPONENTS

The rescission has significant potential implications for developers, including energy and infrastructure project proponents, water operations, and landowners:

• Narrower Scope of “Take”: Habitat disturbance alone (including land grading, vegetation removal, streambed alteration, and water operations) occurring without direct or intentional injury to individual listed animals may no longer independently trigger the need for an ITP under ESA Section 10 or an incidental take statement under Section 7 consultation. For example, under the rescission, loggers could cut trees containing the nests of endangered or threatened birds, such as the northern spotted owl, without triggering take liability, so long as the birds are not physically present in the tree when cut.
• Reduced Permitting Burden: Fewer projects may require ITPs or habitat conservation plans, potentially reducing compliance costs and project timelines for energy development, infrastructure, telecommunications, transportation, and other land-disturbing activities.
• Continued Uncertainty: A coalition of conservation and fishing organizations — including the Environmental Protection Information Center, Western Environmental Law Center, Klamath-Siskiyou Wildlands Center, and Cascadia Wildlands — has announced plans to file suit challenging the rescission in the Northern District of California (within the Ninth Circuit). The anticipated litigation creates substantial uncertainty regarding whether the rescission will survive judicial review or be stayed prior to or shortly after its mid-September effective date.
• Risk of Inconsistent Regional Enforcement: Absent clear regulatory guidance and with litigation pending, federal agencies and regional offices may apply varying interpretations of what constitutes “harm” and “take,” creating unpredictability for multi-jurisdictional projects.
• Related Deregulatory Actions Pending: Forthcoming agency actions related to Section 7 consultation procedures and critical habitat designation processes remain in progress and may further alter the regulatory landscape.

CONCLUSION

Today’s final rule represents the most significant narrowing of ESA “take” enforcement in decades, but its practical impact remains uncertain in light of anticipated judicial challenges. The rule’s reliance on Loper Bright’s overruling of Chevron deference to overturn decades of settled regulatory interpretation will be closely scrutinized by the courts. Project proponents with projects that have historically been subject to ESA incidental take permitting for habitat-based impacts should carefully evaluate their individual circumstances before making changes to their compliance strategies.

If you have questions about the implications of this rule for your projects or operations, please contact a member of Allen Matkins’ Natural Resources practice group.