In the current regulatory climate, environmental claims are no longer just the domain of the marketing department: they are significant legal representations. The gap between “aspirational branding” and “factual substantiation” has become a primary target for class-action lawsuits and regulatory actions around the globe. A recent study found that 96% of companies making net-zero pledges exhibit greenwashing risk factors. That’s significant when almost two-thirds of the Forbes Global 2000 have net zero targets and 137 of 198 national governments have net zero targets.

For startups, the stakes are particularly high. A single greenwashing suit can drain early-stage capital and permanently tarnish a brand before it even scales. To move from vulnerability to defensibility, companies must treat climate claims with the same rigor as financial reporting.

The Pillars of a Defensible Climate Claim

To survive legal scrutiny, an environmental claim must be rooted in evidence rather than intent. If your company is claiming “Net Zero” status or “Carbon Neutrality,” its defense rests on four critical pillars:

• Measurable Targets: Vague promises are a liability. Claims must be backed by specific metrics, typically measured in tons of carbon dioxide equivalent (CO2e).

• Verified Data: Self-reporting is rarely enough. Defensibility requires third-party verification (such as ISO 14064 or limited assurance from an auditor) to prove that the numbers are accurate.

• Timebound Commitments: A claim of “Net Zero” is meaningless without a roadmap. This includes near-term (2030) and long-term (2040/2050) milestones that show a clear trajectory of reduction.

• Documented Governance: Who is accountable? Legal defensibility is strengthened when environmental performance is tied to board-level oversight and internal controls.

What “Net Zero” Actually Means Under Today’s Standards

In many jurisdictions, “Net Zero” implies a 90%-95% absolute reduction in emissions, with only the remaining 5%-10% emissions being offset. This is the “gold standard” for climate claims and is based on:

1. The Science Based Targets initiative (SBTi)

The SBTi Corporate Net-Zero Standard is the most influential source for this figure. It is the world’s first framework for corporate net-zero target setting.

• The Rule: To claim “Net Zero” under this standard, a company must achieve long-term deep decarbonization of 90%–95% across its entire value chain (Scopes 1, 2, and 3) by 2050 at the latest.

• Adoption: While SBTi is a non-governmental organization, many regulators (including the UK’s CMA and the New York Attorney General) have used a company’s adherence to (or departure from) SBTi standards as evidence of whether their climate claims are “credible” or “fraudulent.”

2. UN High-Level Expert Group (HLEG) – “Integrity Matters”

Commissioned by the UN Secretary-General to combat greenwashing, the HLEG 2022 report (“Integrity Matters”) established the criteria for “non-state entities” (companies and cities).

• The Rule: It explicitly states that “Net Zero” requires deep absolute emission reductions. It prohibits counting carbon offsets toward a company’s interim emissions reduction targets.

• Alignment: It aligns with the IPCC’s “1.5°C pathways,” which necessitate near-total elimination of emissions, leaving only a “residual” 5%-10% to be neutralized via permanent carbon removal.

3. EU Greenwashing & Green Claims Directives

The European Union has moved to codify these definitions into law through two major pieces of legislation:

• Empowering Consumers for the Green Transition (ECGT): Adopted in early 2024, this directive bans claims that a product has a neutral, reduced, or positive environmental impact based solely on carbon offsets.

• The 2040 Climate Target: In late 2025, the EU reached a provisional agreement for a 90% net GHG reduction target by 2040 for the entire union, further cementing the “90% reduction” figure as the legal baseline for what a “Net Zero” trajectory looks like.

• Banned Terms: generic terms, like “green” or “eco-friendly” are effectively banned in the EU and high risk in the US.

4. UK Competition and Markets Authority & Advertising Standards Authority

In the UK, the CMA (Green Claims Code) and the Advertising Standards Authority (ASA) have ruled against companies making “Carbon Neutral” or “Net Zero” claims that rely heavily on offsets.

• The Reasoning: Consumers generally understand “Net Zero” to mean the company has fundamentally changed its business to stop polluting. If a company has only reduced emissions by 20% and offset the rest, claiming “Net Zero” is considered a “material omission” of fact. The ASA’s carbon‑neutral and net‑zero guidance makes clear that claims based mainly on offsetting, without clear explanation of the limited role and quality of offsets, are likely to mislead; in a series of rulings, the ASA has treated unqualified “carbon neutral” statements as problematic where advertisers relied largely on cheap, avoidance‑type offsets and did not explain that they had made only limited absolute emissions cuts.

“Net Zero” versus “Carbon Neutral”

Green-Light vs. Red-Light Claims

Lessons to Avoid Greenwashing and Climatewashing Suits and Investigations

Be transparent. Explain when carbon neutrality is achieved through offsets and what kind of offsets. Avoid implying deep structural decarbonization when only modest reductions have occurred. Avoid broad “we are carbon neutral” messaging where only a subset of operations or products is covered.

Know the rules. Jurisdictions have different rules about what you can say, how you can say it, and what type of backup you need. A good rule of thumb across jurisdictions is to avoid generality and vagueness. 

Provide context. Don’t focus only on a single environmentally beneficial initiative when it’s not the only thing in your business or only a small portion of your business. Provide details or elements that show both low-carbon and high-carbon aspects of your business. Qualify anything that needs to be qualified to be clear.

Substantiate now. Get the backup (substantiation) for all numbers that you are going to use – in advance – and make sure that they match your other published numbers. Your CIM should match your website. It should match any reports you have created, white papers, and presentations. The same goes for every other claim in your materials and statements that you make when talking about your business or pitching your company. Keep documentation of the numbers, data, and claims.

Building a Foundation of Integrity

The goal isn’t to stop talking about your environmental progress, it’s to talk about it accurately. By focusing on documented governance and verified data, you turn your environmental strategy from a potential legal liability into a verified competitive advantage.