For years, Scope 3 was a reporting exercise. A company estimated its value chain emissions, disclosed the number, and moved on. Nobody outside the sustainability team looked too closely, because nobody outside the sustainability team was accountable for it.
That's changing, and the reason is straightforward: most of a company's emissions sit outside its own operations. Supply chain emissions run on average 26 times higher than a company's own operational footprint, according to CDP and Boston Consulting Group, so a buyer's climate targets depend heavily on data they don't hold themselves. The share of companies building sustainability metrics into supplier scorecards has climbed from 38% in 2020 to 64% today, per MIT's Center for Transportation & Logistics. A supplier who can't produce emissions data isn't just fielding a follow-up email, increasingly, they're being marked down on a scorecard that feeds into the sourcing decision.
Two things have pushed this further this year: the regulatory scope narrowed, and the requests are now coming from procurement rather than sustainability teams.
The EU's CSRD went through a real simplification in 2026. The Omnibus I package, approved by the European Council in February, narrowed the companies required to report from roughly 50,000 down to around 5,000, applying now only to firms with more than 1,000 employees and over €450 million in annual turnover. That's a real reduction in scope, but it doesn't mean less scrutiny for the companies still in it. Scope 3 reporting stays mandatory for every in-scope company where those emissions are material, and for most companies, that materiality test isn't close.
At the same time, the methodology expected of the companies still in scope has tightened. The GHG Protocol's Scope 3 Phase 1 update, published as a draft in March 2026, moves toward tighter data quality tiers and requires companies to label their Scope 3 data as verified, partly verified, or not verified, publicly. California's SB 253 adds a further layer, requiring Scope 3 disclosure from large firms starting in 2027. Fewer companies are directly obligated, but the ones that are face more detailed expectations than they did a year ago.
The requests are also coming from a different part of the business than suppliers might expect. It's less often a sustainability team compiling an annual report, and more often a procurement team accountable for their own company's targets. 81% of procurement leaders now say ESG factors shape their purchasing decisions, while 85% say finding suppliers who can meet that bar is difficult. Some large buyers have written this into formal policy: Nestlé, Coca-Cola, and PepsiCo have required supplier engagement covering 70% of their emissions since 2024, with an expectation that suppliers set their own science-based targets. For those suppliers, this sits inside the sourcing conversation, not a separate sustainability disclosure.
In practice, that usually means moving past spend-based estimates, a figure produced by multiplying spend by an industry average. Buyers are increasingly asking for primary data specific to what's actually being supplied, a visible reduction trajectory rather than a single-year snapshot, and some level of third-party verification behind what's reported. It's also worth noting the standard isn't "100% primary data everywhere": SBTi's own criteria only require Scope 3 targets to collectively cover 67% of total emissions, through some combination of reduction targets and supplier engagement. Even so, a supplier without a credible plan for the remaining gap is the one more likely to be deprioritised, since that plan is often what a buyer's own reporting depends on.
The consequences here tend to show up quietly. Suppliers who can't produce the data don't always get a direct warning, more often, they're deprioritized in a tender, dropped from a preferred-supplier list, or left out of a renewal conversation without it being framed as a climate issue. Because this happens inside procurement processes rather than public disclosures, it's often not visible until a renewal simply doesn't happen.
None of this means every supplier needs a complete emissions program immediately. It means the expectations for staying in consideration have shifted: being able to show a reduction trajectory rather than just a current snapshot, primary data specific to what's actually being supplied rather than an industry average, and a reasonably clear answer for whatever emissions can't yet be eliminated.
Suppliers who prepare this ahead of time are generally in a stronger position than those who put it together only once a buyer asks.