Trending Environmental Lawsuits: Climate Liability, PFAS, and EPA Rollbacks

Trending environmental lawsuits in 2026 center on one Supreme Court case that could reshape the entire field, a surge of state and city suits against oil companies, a federal rollback of the greenhouse gas endangerment finding, PFAS drinking water settlements worth more than $23 billion, and a growing wave of litigation accusing plastics and consumer companies of deceptive environmental marketing. Here is where the biggest fights stand.

The Supreme Court Case That Could Reshape Climate Liability

The most consequential environmental case in the country is Suncor Energy (U.S.A.) Inc. v. County Commissioners of Boulder County (No. 25-170). The Supreme Court agreed to hear it on February 23, 2026.¹ Boulder County and the City of Boulder sued Suncor and ExxonMobil in 2018 under state tort law, alleging the companies caused climate change injuries while concealing the dangers of fossil fuel use. Colorado’s Supreme Court let the claims proceed, and the companies appealed.²

The question before the Court is whether federal law preempts state-law tort claims that seek relief for injuries tied to interstate and international greenhouse gas emissions.³ A ruling for the companies could effectively shut down dozens of similar climate-damage suits across the country. The Trump administration has urged the Court to reverse the Colorado ruling. Petitioners filed their merits brief on May 14, 2026, with the respondents’ brief due by July 27, and oral arguments are expected in the fall.⁴

The ripple effects are already visible. Defendants in climate suits in Hawaii, New Jersey, and Washington have asked trial courts to pause proceedings until the Supreme Court rules, calling the decision potentially dispositive. The Maryland Supreme Court denied a similar stay request in the Baltimore case in March 2026.²

State and City Suits Against Fossil Fuel Companies

Even before the Supreme Court weighs in, the docket of state and local climate suits is vast. Eleven state attorneys general and dozens of city, county, and tribal governments across at least a dozen states have filed suits alleging that fossil fuel companies knowingly contributed to climate change and misled the public. The jurisdictions behind these cases represent more than one in four Americans.⁵

Several cases have survived motions to dismiss and are moving toward discovery and trial, including suits brought by Boulder, Honolulu, the District of Columbia, Massachusetts, Vermont, Minnesota, and Connecticut. Not every case has survived. A North Carolina Superior Court dismissed Town of Carrboro v. Duke Energy Corp. in February 2026, ruling that climate-damage claims were nonjusticiable under the political question doctrine and calling the attribution of specific climate impacts to one company’s conduct a “futile endeavor.”²

Climate Superfund Laws and Liability Shields

Two parallel legislative trends are now generating their own litigation. New York and Vermont have enacted “climate superfund” laws making fossil fuel companies pay for a share of historic emissions. New York’s version seeks roughly $75 billion from energy companies through 2050, or about $3 billion per year, and about a dozen other states are considering similar bills.⁶

The federal government has moved to block them. In April and May 2025, the Department of Justice sued Hawaii, Michigan, New York, and Vermont, arguing the laws are preempted by the Clean Air Act and violate the Constitution’s foreign affairs and commerce provisions.⁷ DOJ filed motions for summary judgment against Vermont in September 2025 and against New York in August 2025.⁸ United States v. New York (No. 1:25-cv-03656, S.D.N.Y.) remains in summary judgment briefing as of mid-2026.⁹ A 22-state coalition of Republican attorneys general has also filed its own challenge to the New York law.

Running the other direction, Utah became the first state to enact a climate liability shield when Governor Spencer Cox signed House Bill 222 on March 23, 2026, effective May 6, 2026.¹⁰ The law bars civil or criminal liability for damages from greenhouse gas emissions unless a plaintiff proves by clear and convincing evidence that the defendant violated an enforceable emission limit or permit term and that identifiable damage directly resulted.¹¹ Lawmakers in Oklahoma, Louisiana, Tennessee, and Iowa are working on similar bills, and Representative Harriet Hageman of Wyoming has said she is drafting federal legislation to grant broad immunity to energy companies.¹²

The Challenge to the EPA Endangerment Finding Repeal

On February 12, 2026, the EPA finalized the repeal of the 2009 greenhouse gas endangerment finding, the scientific determination that carbon dioxide and other greenhouse gases threaten public health and welfare. The agency called it the “single largest deregulatory action in American history.”¹³ The agency simultaneously eliminated clean vehicle emission standards that had relied on the finding.¹⁴

On March 19, 2026, a coalition of 23 states, Washington D.C., the U.S. Virgin Islands, and several local governments, led by Massachusetts Attorney General Andrea Joy Campbell, filed a petition for review in the D.C. Circuit (Case No. 26-1061).¹⁵ The coalition argues the repeal contradicts the 2007 Supreme Court ruling in Massachusetts v. EPA, which held that greenhouse gases are air pollutants under the Clean Air Act. Health and environmental groups have filed a separate challenge in the same court. Briefing schedules had not been set as of mid-2026.

The repeal may carry a counterintuitive side effect. Legal experts, including the Sierra Club, have suggested that eliminating the endangerment finding could increase fossil fuel companies’ exposure to common-law liability by undermining their defense that the Clean Air Act displaces such claims.¹⁶

PFAS “Forever Chemical” Settlements and Deadlines

The largest environmental settlements in recent years involve PFAS contamination of drinking water. In 2024, 3M agreed to pay up to $12.5 billion and DuPont agreed to pay $1.185 billion to help public water utilities test for and remove PFAS. A related $10.3 billion class action settlement covering PFAS-containing firefighting foam was approved on March 29, 2024.¹⁷

Those settlements are now in active distribution. Phase 2 deadlines for water systems that had not yet detected PFAS run through the summer of 2026, with action fund claims due by July 31 for both the 3M and DuPont funds. Water systems that miss these deadlines forfeit the right to future litigation against the companies over PFAS in drinking water.¹⁸

The regulatory picture is shifting at the same time. In 2024, the EPA finalized the first national limits for six PFAS compounds in drinking water. In January 2026, a federal appeals court rejected the Trump administration’s request to vacate the rules for four of those compounds, though legal challenges remain pending. The administration’s EPA has said it will stop defending the regulation of four of the six chemicals, prompting NRDC and Earthjustice to intervene to defend the original health standards.¹⁹ More than 300 separate PFAS contamination lawsuits have been filed since 2018.²

Plastics Pollution Suits Against Oil and Beverage Giants

A wave of litigation targeting the plastics industry has drawn frequent comparisons to the lawsuits against Big Tobacco. The most prominent case is California’s suit against ExxonMobil (People v. Exxon Mobil Corp., No. CGC-24-618323), filed by Attorney General Rob Bonta in September 2024, alleging a decades-long campaign of deception about the recyclability of plastics.²⁰ ExxonMobil removed the case to federal court, a federal judge sent it back to state court in February 2025, and as of May 2026 ExxonMobil is appealing that remand to the Ninth Circuit, arguing the case belongs in federal court because the alleged pollution affects navigable waterways.²¹

Other plastic pollution suits are advancing on parallel tracks:

Connecticut’s trial against Reynolds Consumer Products over claims that Hefty “recyclable” trash bags were deceptively marketed was scheduled for May 2026.²²
Baltimore’s public nuisance and false advertising case against PepsiCo tied to plastic waste continued through spring 2026 briefing on the nuisance claims.
Los Angeles County’s case against PepsiCo and Coca-Cola, alleging disinformation about plastic bottle recyclability, is set for trial in October 2027.
A federal court denied ExxonMobil’s motion to dismiss a public nuisance claim in Sierra Club v. ExxonMobil in September 2025.

Youth Climate Cases

Youth plaintiffs scored a major win in Montana, where the state Supreme Court affirmed in December 2024 that the Montana Constitution’s guarantee of a “clean and healthful environment” includes a stable climate system.²³ The ruling struck down provisions of the Montana Environmental Policy Act that had excluded greenhouse gas emissions from environmental review.

The Montana Legislature responded in 2025 by passing three new laws plaintiffs say undermine the decision: one stripping the environmental review process of enforcement power, another narrowing review scope to exclude indirect impacts, and a third barring the state from adopting air pollution standards stricter than federal ones. In January 2026, 16 youth plaintiffs, including 13 from the original case, filed Held v. State of Montana II in district court to challenge all three laws.²⁴ The state has moved to dismiss portions of the case and to transfer venue to a rural county far from the capital, and as of mid-2026 the court has not ruled on either motion.²⁵

The federal youth case, Juliana v. United States, came to a definitive end in March 2025 when the Supreme Court declined to hear the plaintiffs’ appeal.²⁶ In September 2025, fifteen of the original Juliana plaintiffs filed a petition with the Inter-American Commission on Human Rights alleging that U.S. energy policies violate their rights to life, health, and dignity under the American Declaration of the Rights and Duties of Man. The Commission typically takes about a year to respond.²⁷

Challenges to Trump Administration Environmental Rollbacks

Environmental groups have filed a barrage of suits challenging rollbacks across the federal government. The Center for Biological Diversity alone has filed 112 suits against the administration as of mid-2026, covering endangered species protections, pesticide approvals, border wall construction, and more.²⁸

Among the active challenges:

Multiple groups sued over an 80-million-acre Gulf of Mexico oil and gas lease sale, citing violations of the National Environmental Policy Act.²⁹
The Center for Biological Diversity sued in March 2026 to block the administration from convening the rarely used Endangered Species Committee, the “God Squad,” to grant an exemption for Gulf oil and gas drilling. A federal judge in D.C. declined to block the meeting, citing jurisdictional concerns, and the government has since moved to dismiss the case entirely, with briefing due by late June 2026.³⁰
Earthjustice challenged an EPA process that allowed 68 coal plants to email the agency to obtain exemptions from mercury and arsenic standards.²⁹
NRDC and a coalition sued the EPA in March 2026 for repealing rules limiting mercury, lead, and particulate emissions from power plants.³¹
Environmental groups challenged both FERC’s approval of the Venture Global Calcasieu Pass 2 (CP2) LNG export terminal and the Department of Energy’s export authorization.

Courts have sided with plaintiffs in several early disputes. A federal court nullified the administration’s attempt to open a Pacific Islands marine monument to commercial fishing, a D.C. court ordered the restoration of frozen USDA grants to farmers, and the USDA agreed to restore purged climate data from government websites before a court hearing.²⁹

A separate cluster of suits challenges the termination of clean energy programs authorized by the 2022 Inflation Reduction Act. In January 2026, a D.C. court found that the Department of Energy’s termination of grants violated the Fifth Amendment and vacated terminations for seven grants worth $27.6 million, though it later denied permanent injunctive relief. States including Arizona, Maryland, Virginia, and California have filed suits over Solar for All clawbacks and program cancellations, with cross-motions for summary judgment pending.³²

California Climate Disclosure Laws and Corporate Greenwashing

California’s two corporate climate disclosure laws face an ongoing legal challenge in Chamber of Commerce v. Sanchez (No. 25-5327, 9th Cir.). SB 253 requires companies with over $1 billion in annual revenue to report greenhouse gas emissions, and SB 261 requires companies above $500 million to report climate-related financial risks. A business coalition led by the U.S. Chamber of Commerce challenged both laws on First Amendment, preemption, and Commerce Clause grounds.³³

The Ninth Circuit heard oral arguments on January 9, 2026, but has not yet ruled. The panel expressed significant concern about SB 253’s Scope 3 emissions reporting requirements, which cover a company’s entire supply chain, and asked the state whether those provisions could be severed if found unconstitutional. SB 261 remains under a court-issued injunction while the appeal proceeds. SB 253 is technically in effect, with initial emissions reports due by August 10, 2026.³⁴ Summary judgment briefing is scheduled for the summer regardless of the appellate outcome.³⁵

Consumer-facing greenwashing litigation has also grown. Tracking by TINA.org found over 150 greenwashing class actions filed as of early 2025, targeting food, apparel, tech, and personal care companies. About 74% of tracked cases had been settled or dismissed, and 26% remained pending.³⁶ A federal court dismissed claims that Apple misled consumers by marketing certain Apple Watches as “carbon neutral,” finding the plaintiffs had not plausibly alleged the claims were false. Similar claims against the makers of Vuse vaping products were dismissed after a court found that a reasonable consumer would not interpret “carbon neutral” as meaning zero emissions. Courts have also dismissed greenwashing claims against Allbirds, H&M, Lululemon, Nike, and multiple airlines. Where cases have settled, consumers have sometimes won monetary relief and companies have agreed to change their marketing: of 35 settlements with disclosed terms, 14 included payments to class members and 11 included marketing changes.

1
SCOTUSblog. Supreme Court Agrees To Hear Case on Colorado Dispute Over Climate Change
2
Columbia Law School Sabin Center. Climate Litigation Updates
3
PBS NewsHour. Supreme Court Agrees To Hear Arguments From Oil and Gas Companies Trying To Block Climate Change Lawsuits
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U.S. Supreme Court. Docket for No. 25-170, Suncor Energy v. Boulder County
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Climate Integrity. Oil Lobby Makes Killing Climate Lawsuits a 2026 Priority
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ESG Today. 22-State Coalition Sues To Block New York Law Charging Oil Companies $75 Billion
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U.S. Department of Justice. Justice Department Files Complaints Against Hawaii, Michigan, New York, and Vermont
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U.S. Department of Justice. Justice Department Files Motion for Summary Judgment To Challenge Vermont’s Climate Superfund Law
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Climate Case Chart. United States v. New York
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NPGA. Utah Enacts Climate Shield Law
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Climate Court. State Climate Liability Shields in 2026
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New York Times. Oil Liability Shield Laws and Climate Lawsuits
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Spotlight PA. EPA Lawsuit Greenhouse Gas Trump Rollback
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Clean Air Task Force. US EPA Sued Over Illegal Repeal of Climate Protections
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Climate Case Chart. Massachusetts v. EPA
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E&E News. 5 Climate Court Battles To Watch in 2026
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Chemical & Engineering News. PFAS Settlement
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National League of Cities. PFAS Settlement Deadlines Updated
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NRDC. PFAS Settlement Money for Water Utilities Poised To Evaporate
20
Climate Case Chart. People v. Exxon Mobil Corp.
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Courthouse News. ExxonMobil Fights To Send California Pollution Deception Lawsuit Back to Federal Court
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Plastics Litigation Tracker. Plastics Litigation Tracker
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Justia. Held v. State, 2024 MT 312
24
Daily Montanan. Youth Climate Plaintiffs File Suit in State District Court
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Our Children’s Trust. Montana – Our Children’s Trust
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New York Times. Supreme Court Climate Lawsuit Juliana Children
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Jones Day. American Youth Climate Litigants Take the International Stage
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Earthjustice. Trump Environment Lawsuits
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Clearinghouse. Center for Biological Diversity v. Burgum
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NRDC. How NRDC Is Fighting Against the Trump Administration
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IRA Tracker. IRA Litigation Tracker
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