Identity verification (KYC, consumer) + business verification (KYB) + sanctions screening + onboarding decisioning. Tracked in a single bucket because most vendors (Alloy, Persona, Sumsub, Stripe Identity) sell both; KYB specialists like Middesk and Baselayer sit alongside them. Fraud-orchestration and transaction-monitoring vendors (Sardine, Sift, Forter, ComplyAdvantage) belong to this compliance layer but are counted in a separate bucket, so they don't appear in the ranking below. Compliance vendors are the most under-disclosed layer — see Section 05.