Add commercial identity research corpus and binding concepts

Record deep research on commercial identity coupling across theory, law,
regulation, and software (KYC, LEI, DUNS, eIDAS, CRM). Introduce Commercial
Commitment, Legal Person, and Beneficial Owner to the canon model and document
the fluid-to-bound identity gradient in the conceptual model.

OpenQuestions.md

@@ -159,6 +159,56 @@ Source notes use:
 
 No separate bibliography file added.
 
+## Commercial Identity Research (2026)
+
+Deep research recorded under `research/commercial-identity/`. Key finding:
+identity and commerce are coupled in practice through **commercial binding** —
+evidenced obligations that raise counterparty reliance and make identity less fluid.
+
+### Commercial Commitment placement
+
+**Status:** Tentatively resolved — first-class Relationship-layer concept.
+
+Contracts, subscriptions, payment mandates, and regulated onboarding acceptance
+map to **Commercial Commitment** attached to Commercial Relationship or
+Commercial Record. See `commercial-identity-synthesis.md`.
+
+**Remaining:** Whether pipeline stages (CRM Opportunity) are commitments or
+downstream-only.
+
+### Beneficial Owner modeling
+
+**Status:** Open.
+
+KYC sources require natural persons behind legal entity customers. Candidate:
+Beneficial Owner as Natural Person + Ownership/Representation with Evidence.
+
+**Decision needed:** Dedicated relationship type vs. Ownership subtype with
+`beneficial` role metadata.
+
+### Reputation as canon concept
+
+**Status:** Open — leaning toward Evidence Source aggregation.
+
+Credit scores (PAYDEX), performance history, and repeat-play trust may not need
+a separate Reputation entity if modeled as Evidence Source + Trust Relationship
+with temporal scope.
+
+### Registry identifier subtype
+
+**Status:** Open.
+
+LEI, DUNS, UEI, and company registration numbers share renewal, authority, and
+cross-registry linking needs. Candidate: authoritative **Registry Identifier**
+subtype with renewal Lifecycle State.
+
+### Payment credential boundary
+
+**Status:** Open (downstream-heavy).
+
+Whether payment methods on Commercial Record map to Credential in canon or remain
+PCI-scoped downstream artifacts only.
+
 ## New Questions From Corpus Review
 
 ### Cerbos derived roles vs. explicit relationships