Cases / Law, regulation and treaties · United States · 2018
US Supreme Court hears Boulder County's climate suit against Suncor and Exxon
Short record: the main facts, with sources. A full case file has not been prepared.
Nature's voice · report
No measurement of the harm done to me here is on record.
Did nature suffer? Not measured.
Not on record
- The record does not name which of my species, waters, soils or forests were harmed.
The US Supreme Court heard oral arguments on 5 October 2026 in the case Suncor and ExxonMobil brought against Boulder County's 2018 climate suit, and a decision is pending. A ruling could affect 35 to 60 similar cases.
What?
The US Supreme Court heard arguments on 5 October 2026 in Suncor and ExxonMobil's case against Boulder County's 2018 climate suit; a decision is pending. Straight Arrow News
Where?
Boulder County, Colorado; US Supreme Court in Washington DC Straight Arrow News
When?
Suit filed 2018; oral arguments 5 October 2026; decision pending Straight Arrow News
Who?
Gained
- ExxonMobil — Reported 2024 profit of $33.7bn; $36.0bn paid to shareholders
Lost
- Boulder County — Its 2018 suit is now before the Supreme Court Straight Arrow News
Harmed
None on recordWhy?
Not stated in the sources reviewed.
How?
Local-government suits against fossil fuel companies, now before the US Supreme Court; the Trump administration supports the companies, as reported. Smart Cities Dive
6 of 6 questions answered from the record
What happened
The record, in order.
Boulder County sued Exxon and Suncor in 2018 in a climate case; the US Supreme Court heard the companies' challenge on 5 October 2026, and a decision is pending (Smart Cities Dive).
Dozens of municipalities, 11 states, Washington DC and two tribes have filed similar suits (Smart Cities Dive).
The Trump administration supports the companies, and the ruling could affect 35 to 60 similar cases (Straight Arrow News).
ExxonMobil reported a 2024 profit of $33.7bn and paid $36.0bn to shareholders.
In court and with insurers
Every proceeding and every insurer decision on record.
Lawsuits and rulings
- 2018–OngoingSuncor and ExxonMobil v. Boulder CountyUS Supreme Court · Civil · Suncor Energy; ExxonMobil → Boulder County
Oral arguments held 5 October 2026; decision pending. Straight Arrow News
- 2025–OngoingExxonMobil v. Bonta and othersTexas court (name not given in sources) · Civil · ExxonMobil → California Attorney General Bonta; four environmental groups; Intergenerational Environmental Justice Fund
Defamation suit filed in Texas in January 2025. In February 2026 the claims against the environmental groups were dismissed for lack of jurisdiction; claims against the attorney general were kept, and an appeal is ongoing.
Insurers
No insurer decision on record.
What we don't know
Undisclosed, unproven, untried: recorded as data.
Nature
- Not measured Harm to nature: The record holds no measurement of harm to nature.
Record
- Insufficient Reported but not verified: ExxonMobil's 2022 record profit of $55.7bn.
- Insufficient Reported but not verified: New York's 2019 investor-deception case against Exxon was won by the company; Massachusetts's 2019 consumer-deception case was still in document review in 2026.
- Insufficient Reported but not verified: 2025 Justice Department suits against Hawaii, Michigan, New York and Vermont over their climate actions.
- None on record The sources give 2027 as the expected decision date for the Supreme Court case; this is not confirmed.
- None on record No criminal penalty for Exxon's climate statements is on record in the sources reviewed, and no executive was personally prosecuted.
Did the harm stop?
Not stated in the sources reviewed.
Who paid?
Not stated in the sources reviewed.
Sources
Voices on record: — Company or project— Government and regulators— Courts✓ Press and investigations— Communities and civil society— Researchers
Press and investigations
- Supreme Court to hear high-stakes climate case tomorrowStraight Arrow News · 2026-10-04
- Supreme Court hears arguments in Boulder County, Colorado climate caseSmart Cities Dive · 2026-10-06
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