Corporate Sustainability Reporting & ESG Disclosure Advisory

Gasilov Group helps mid-market and enterprise companies meet disclosure requirements under the ISSB standards (IFRS S1 and S2), California SB 253 and SB 261, the EU's CSRD, and the UK's SRS S1 and S2. We handle double materiality assessments, Scope 1-3 baselining, data architecture, and disclosure drafting that survives external assurance.

Engagements are led by Seyfi Gasilov, our partner for Sustainability Reporting & Governance, who works on CSRD and ESRS compliance, ISSB, internal controls, and supply-chain due diligence.

Get disclosure-ready under ISSB, California, CSRD, and UK SRS, all before your next filing deadline

The global baseline is the ISSB's standards, IFRS S1 and S2, with roughly 40 jurisdictions adopted or moving as of early 2026; they set the structure investors expect whether or not your home market mandates them yet.

In the US, California is the binding driver. Companies above $1B in revenue doing business in California must report Scope 1 and 2 emissions under SB 253 by August 10, 2026, with Scope 3 in 2027, and its climate-risk counterpart SB 261 (for companies above $500M) is built on the same TCFD basis as IFRS S2, currently subject to a Ninth Circuit injunction with CARB holding enforcement pending appeal.
For the first SB 253 cycle, CARB is exercising enforcement discretion: good-faith filers can submit the Scope 1 and 2 data they already have, no third-party assurance is required, and no penalties apply.
The EU's CSRD still applies if you have significant European operations, but the 2026 Omnibus removed an estimated 80 to 85% of previously in-scope companies, so far fewer US groups are caught than a year ago.

If your company is in scope, or if you supply a company that is, you'll need audit-ready emissions data, documented controls, and disclosures written to the datapoints each regime requires.

According to KPMG's 2024 Survey of Sustainability Reporting, 96% of the world's 250 largest companies publish sustainability reports, so the question has moved from whether to report to whether the numbers survive assurance.

How We Deliver Reporting That Passes Assurance

A typical reporting engagement runs in five stages: materiality, data, framework alignment, governance, and narrative.

Regulators and investors read these disclosures to judge your company, and an external assurance provider tests them under ISSA 5000, the IAASB standard effective for reporting periods beginning on or after December 15, 2026. We build each engagement with the evidence a reviewer asks for already in place.

Materiality & Topic Prioritization – We run the materiality assessment your regime requires: financial materiality alone under ISSB, where the test is what affects enterprise value, or double materiality under CSRD, which adds your effect on people and the environment. The output is a defensible list of impacts, risks, and opportunities tied to the ESRS topical standards, which sets what you disclose and what you can leave out.

Data Collection & Control Design – We establish data lineage for each metric back to its system of record, so a number in the report reconciles to the meter reading or invoice behind it. For emissions that means GHG Protocol Scope 1, Scope 2 on both a location and market basis, and the material Scope 3 categories, with emission factors and calculation methods held in version-controlled files a reviewer can re-perform.

Regulatory & Framework Alignment – We align disclosures across the regimes you report under: CSRD and the revised ESRS (which cut mandatory datapoints by about 61% under the Omnibus), ISSB's IFRS S1 and S2, California SB 253, and the voluntary frameworks investors still ask for (GRI, SASB, CDP, TNFD). Where you report under both ESRS and ISSB, we use the IFRS-EFRAG interoperability guidance to avoid duplicate work and check where the new ESRS reliefs have no ISSB equivalent, so nothing falls through.

Stakeholder & Governance Integration – We build the governance disclosures ESRS 2 requires (the one standard that stays mandatory regardless of your materiality result), including how your board oversees the identified impacts, risks, and opportunities and where that oversight sits in existing committees. In practice that means putting sustainability disclosure on the same review calendar as your 10-K, so the board signs off on consistent numbers and narrative.

Reporting Narrative & Disclosure Quality – We draft the disclosures against the specific ESRS datapoints your materiality result kept, using the revised standards' more flexible, narrative treatment of policies, actions, and targets. We prepare the report for digital tagging under the ESRS taxonomy, which the 2026 revision simplified to match the reduced datapoint set, so the filing is machine-readable without a separate scramble at the end. Claims are drafted with the EU's Empowering Consumers Directive in view, which from September 27, 2026 bans generic claims like 'eco-friendly' unless backed by recognized certification; Sourcing Journal quoted one of our partners on what that shift means for brand messaging.

Not Sure If You Are In Scope? Start With Our Free Regulatory Readiness Assessment:

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Who This Is For

US companies with California operations

Scope 1 and 2 reporting under SB 253 is live, Scope 3 follows in 2027, and SB 261's biennial climate-risk report sits on top.

Companies in ISSB markets or with global investors

If you operate or raise capital in one of the ~28 jurisdictions adopting IFRS S1 and S2, or your investors expect them, ISSB is your baseline even without a US federal mandate

Companies with significant EU operations

CSRD still applies to non-EU groups above the post-Omnibus thresholds (more than €450M in net EU turnover with a qualifying EU subsidiary or branch), though far fewer are caught after the 2026 changes

Suppliers to in-scope companies

Data requests now cascade from in-scope customers through their supply chains. Mining Technology quoted the firm on how buyers now demand auditable emissions numbers from suppliers, with tariffs and lost contracts as the penalty.

Frequently Asked Questions

Is sustainability reporting only for large companies?

No. Mandatory reporting applies to large companies, but mid-market suppliers increasingly receive data requests from CSRD-scoped customers, investors, procurement platforms, and public tenders. Under the Omnibus value chain cap, suppliers below 1,000 employees can limit these requests to the Voluntary SME Standard (VSME). Even so, preparing audit-ready emissions data and basic ESG disclosures is often required to retain enterprise accounts.

Which frameworks are used for sustainability reporting?

The ISSB standards (IFRS S1 and S2) are the global baseline, adopted or progressing in around 28 jurisdictions including the UK, Japan, Singapore, Australia, and Canada, and they replace TCFD. US companies above California's thresholds report under SB 253 and SB 261, with SB 261 built on the same TCFD basis as IFRS S2. Companies with significant EU operations use CSRD and ESRS, though the Omnibus narrowed that scope. GRI, SASB, CDP, and TNFD remain in use for voluntary and investor-led disclosure.

How do we determine which ESG topics to report on?

For CSRD, topic selection uses a double materiality assessment: impact materiality (how your operations affect people and the environment) combined with financial materiality (how sustainability issues affect business performance). The output is a prioritized list of Impacts, Risks, and Opportunities tied to ESRS topical standards. Under revised ESRS, companies can report at topic, sub-topic, or IRO level to reduce excess granularity.

What changed under the CSRD Omnibus, and does our company still need to report?

The 2026 Omnibus directive (EU 2026/470) , which entered into force on March 18, 2026, raised CSRD thresholds to more than 1,000 employees and more than €450M net turnover, removing approximately 80 to 85% of previously in-scope companies. Wave 2 reporting was pushed to FY 2027 with first reports in 2028. Listed SMEs are fully exempt. Whether CSRD still applies to your company depends on headcount, EU turnover, corporate structure, and customer relationships.

Get Disclosure-Ready

An ISSB and California Readiness Review is a two-week diagnostic that works out your scope under each applicable regime, finds the data gaps against required disclosures, and delivers a prioritized workplan with effort estimates.

Led by Seyfi Gasilov, partner for Sustainability Reporting & Governance.

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