The EU Carbon Border Adjustment Mechanism (CBAM) enters its definitive period in 2026. Free allowances taper on a fixed schedule and reach zero in 2034. The first phase covers six sectors — steel, aluminium, cement, fertilizers, electricity, and hydrogen. Petrochemicals are not yet on the list.

"Not yet listed" is not "exempt." SNSUC transfers crude and derivatives whose downstream buyers sit inside EU supply chains; those customers will soon demand batch-level product carbon footprint (PCF). Whoever builds solid carbon data first captures the EU orders.

The mechanics are concrete. Each batch's energy use, feedstock traceability, and transport emissions are computed into a PCF, then sealed with a SHA-256 proof that third parties can recompute and cannot alter. Cross-chain warehouse-receipt mutual recognition lets one fingerprint satisfy banks and exchanges on both sides of the border.

The compliance red lines stay fixed. Origin screening follows SNSUC's iron rules: Iran remains the only auto-denied origin, and Iraq has been exempt since 2026-10-02. Carbon compliance is a value-add; origin compliance is the gate. The two must not be confused.