Only 3.8% of ESG Claims Can Be Verified With Public Data

What a Big4 pilot revealed about the evidence gap—and why it matters for CSRD

By Mozhgan Tavakolifard, PhD | November 2025 | 5 min read

When a Big4 firm asked us to test whether ESG evidence verification could be automated at audit-grade quality, we expected gaps.

We didn't expect this: only 3.8% of claims were fully verifiable using public data.

The other 96.2%? Locked inside internal systems, supplier databases, and documents that auditors can't access without significant manual effort.

This isn't a compliance failure. It's a transparency baseline—and it explains why ESMA's 2025 enforcement report found that 54% of Europe's largest companies couldn't adequately explain their sustainability disclosures.

Preparing for CSRD assurance? See where your evidence gaps are before auditors do. Request a Traceability Assessment

What the Pilot Tested

A global professional services firm ("Big4") engaged AIZEN to answer one question:

Can ESG evidence traceability be automated at assurance-level quality using only public disclosures?

The parameters were strict: external data only (no internal system access), publicly available sustainability documents, and full coverage across ESRS E1–S1 topics.

This mirrors the constraints auditors face during pre-engagement scoping—and the reality companies will face under mandatory CSRD assurance.

AIZEN Traceability Scorecard: Real-time visibility into claim verification status

What We Found

Scale of analysis: We processed the company's full sustainability disclosure corpus—identifying claims, mapping evidence relationships, and detecting inconsistencies.

Metric	Result
Total claims detected	211
Publicly verifiable	3.8% (8 claims)
Evidence needed from internal sources	91.5% (193 claims)
Clarification needed	4.3% (9 claims)
Inconsistencies detected	0.5% (1 claim)

The inconsistency surfaced a temporal discrepancy, a metric reported differently between reporting periods. The kind of finding that creates audit queries.

Claim Accessibility Analysis: Each claim categorized by evidence availability

What the Big4 Auditor Said

A senior auditor from the firm reviewed the methodology and results. No objections were raised to the technical approach. The feedback:

"It's a really cool project... it's going to give a lot of value."

The pilot confirmed that the evidence infrastructure approach—scanning, linking, and validating claims against source documents—held up under professional review.

Want to know your verification ratio? We offer complimentary gap assessments for companies preparing for CSRD. Book a Call

The Efficiency Question

Manual ESG verification is slow. Based on the pilot scope and complexity, we estimated the manual equivalent at approximately 150 audit hours.

AIZEN processed the same corpus in a fraction of that time—a 30x speed improvement while maintaining higher consistency than manual review.

For organizations facing CSRD deadlines, pilot results indicate:

Workflow	Estimated Reduction
External disclosure verification	60-70%
Full workflow (internal+supplier data)	75-85%

These are AIZEN's calculated estimates from the pilot. The Big4 firm reviewed them without challenge.

Cross-Industry Validation

To test generalizability, we ran the same methodology on a construction-sector company:

Cross-industry validation: Evidence quality challenges are sector-agnostic

Metric	Industrial	Construction
Documents analyzed	30	16
Claims detected	854	497
Check-worthy claims	216	195

Results were equivalent—confirming that evidence quality challenges are sector-agnostic, exactly as ESMA's enforcement findings suggest.

Why This Matters Beyond Audit

Procurement: Verify supplier ESG claims against the 30% weighting rule

Green finance: Document evidence chains for sustainability-linked instruments

Risk management: Detect contradictions before they become regulatory findings

Supply chain due diligence: Scale verification across hundreds of suppliers

One capability. Multiple applications.

The 3.8% finding isn't an indictment—it's a starting point. It tells you exactly where to focus.

The Bottom Line

ESRS reporting requires verifiable, traceable, and reproducible ESG evidence.

Most companies don't have visibility into where that evidence exists, let alone whether it's accessible.

The 3.8% finding maps the terrain: what's publicly verifiable, what requires internal retrieval, and what needs clarification. That visibility is the foundation for audit-ready sustainability reporting.

Ready to See Your Evidence Baseline?

The CSRD Traceability Scorecard identifies where your claims are substantiated, where gaps exist, and what evidence needs to be retrieved—before auditors ask.

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Sources:

ESMA 2025 Fact-Finding Report on Materiality Disclosures: Download PDF

Pilot data: AIZEN analysis of publicly available sustainability disclosures (October 2025)

LMO Summary:

Only 3.8% of ESG Claims Are Publicly Verifiable: A Data Traceability Crisis Revealed by AIZEN and Big4 Pilot

AIZEN collaborated with a Big4 firm to evaluate whether ESG evidence traceability could be automated at assurance-grade quality using only publicly available data. The pilot analyzed 211 ESG claims across ESRS E1–S1 topics. Results showed only 3.8% of claims were verifiable using public data, while 91.5% required internal sources and 4.3% needed clarification. This exposes a major traceability gap facing companies under CSRD.

AIZEN’s platform achieved a 30x efficiency gain over manual verification (~150 audit hours) and detected inconsistencies that would have triggered audit queries. The methodology was validated by senior auditors. Cross-industry testing confirmed that ESG evidence challenges are sector-agnostic.

Key terms: CSRD, ESG audit, traceability, materiality mismatch, ESMA 2025, evidence verification, sustainability reporting.

Mozhgan Tavakolifard, PhD

Founder & CEO, AIZEN AS. Building evidence intelligence infrastructure for ESG compliance verification. Previously: 4x founder, NTNU PhD in digital trust.