Agents & Roles

Context and Problem Statement

PDTF v3 models everyone attached to a transaction as a flat participants[] array discriminated by a role enum, with name, address, organisation, dateOfBirth and email hanging off each entry, and distinguishes privateIndividual from organization only as enum values. This is the participant analogue of the implicit-Property defect (ODR-0005): identity-supplying things (a person, an organisation) are conflated with anti-rigid, externally founded things (being a seller, buyer, conveyancer). Capacity is a casualty — sellersCapacity and the gap between asserted capacity and evidenced authority (probate, power of attorney) collapse a founding legal grant into a free-text enum.

Council Session 001 (Q3) resolved to partition the ontology by ontological concern, reconciling Kendall’s FIBO modules with Guizzardi’s UFO Kind/Role/Relator layering. This ODR is the Agents & Roles module under that partition. It is gated by the identity crux (ODR-0005): Person/Organisation identity criteria and the Address class are shared with the Property work.

Considered Options

• Option A (chosen) — W3C Org ontology (or bespoke opda:) Kind layer with UFO Kind/RoleMixin/Role layering. Places identity where identity actually lives (the person/organisation) while keeping role-play anti-rigid and externally founded; leaves a clean seam to the provenance layer via prov:Agent.
• Option B — Keep the schema shape (one opda:Participant class with a role datatype property). Rejected: reproduces the exact defect — no identity criterion, bearer conflated with role.
• Option C — prov:Agent-only agent layer. Rejected: prov:Agent is deliberately thin and cannot carry the Kind layer (no Person/Organisation distinction, no structured Name).
• Option D — FOAF for the Kind layer. Rejected: overlaps the W3C Org ontology and dct: confusingly, absent from the comparable H&M src/ survey, already deferred by ODR-0002.

Decision Outcome

Chosen option: “Option A — W3C Org / bespoke opda: Kind layer with UFO Kind/RoleMixin/Role layering”, because it places identity where identity actually lives (the person/organisation) while keeping role-play anti-rigid and externally founded, and rules out FOAF.

Adopt a W3C Org ontology (or bespoke opda:) Kind layer with UFO Kind/RoleMixin/Role layering, ruling out FOAF, because it places identity where identity actually lives (the person/organisation) while keeping role-play anti-rigid and externally founded, and leaves a clean seam to the provenance layer via prov:Agent.

Consequences

• Downstream modules MUST consume opda:Address and opda:Name from this module rather than redeclaring them.
• The evidence layer (ODR-0009) MUST attach to the opda:evidencedAuthority slot when a regulated capacity is asserted.
• The role/capacity SKOS schemes (ODR-0011) MUST source their members from the data dictionary’s role enum and labels from the business glossary.
• The TBox remains unfrozen until the W3C-Org-vs-bespoke opda: Kind-layer choice is resolved in a follow-up council session.
• Schema-to-ontology mapping work for participants[] is blocked on this module reaching freeze.

More Information

• Target versions: RDF 1.2 and SHACL 1.2, per the Core-tier pin in ODR-0002.
• Vocabularies: Core (OWL/RDFS/XSD); SKOS for role/capacity schemes (→ ODR-0011); PROV-O for the verification cross-link (→ ODR-0009); DPV for PII annotation on Person/contact leaves (→ ODR-0012); OWL-Time if role-tenure intervals are modelled here. Candidate Kind-layer vocabularies (FOAF ruled out): W3C Org ontology or a bespoke opda: Kind layer.
• Glossary & data dictionary inputs: the role concept scheme (ODR-0011) draws enumerated members from baspi5.json (Buyer, Seller’s Conveyancer, Prospective Buyer, Buyer’s Conveyancer, Estate Agent, Buyer’s Agent…) and skos:definition/skos:prefLabel from the business glossary (Participant, Role, Scheme Operator, Data Provider, Data Recipient, TPP). Each concept carries dct:source to its glossary row or schema leaf path. See ODR-0004 for the term-sourcing convention.
• Deliverables: agents-roles.ttl; Role/Capacity/Status SKOS schemes (→ ODR-0011); DPV PII annotations (→ ODR-0012); SHACL role-play and capacity-evidence shapes (→ ODR-0013).
• Related ODRs: anchor ODR-0003; foundation ODR-0004; gating crux ODR-0005; provenance ODR-0009; enumerations ODR-0011; governance ODR-0012.
• Council deliberation: session-001 Q2 (Kind-layer agent vocabulary), Q3 (partition), Q4 (shared Address/identity).

ODR dependency graph

The diagram below shows how this ODR relates to its declared depends-on and implements links.

Rules

Class hierarchy: Kind, RoleMixin, Role

The diagram shows the UFO-layered class structure for agents and roles as decided in this ODR.

Kind layer (rigid, identity-supplying)

• opda:Person, opda:Organisation — substance Kinds. Identity criteria coordinated with ODR-0005’s category commitments.
• opda:Name, opda:Address — structured datatypes, declared once here and reused by ODR-0005/0008 (single Address class).
• prov:Agent is retained only as the provenance role in claim/verification activities (ODR-0009), not as the Kind-layer agent type.

Role layer (anti-rigid, externally founded)

• opda:Seller, opda:Buyer — RoleMixins, played by a Person or Organisation. Each is specialised by a sortal role (PersonSeller, OrganisationSeller) that carries identity, and founded by the opda:Transaction relator (ODR-0007).
• opda:Proprietor, opda:Conveyancer, opda:EstateAgent, opda:Surveyor, opda:Lender, opda:Insurer — Roles, each founded by the relevant Relator (Proprietor by an opda:Proprietorship).

Role-founding relator pattern

This diagram illustrates how each Role or RoleMixin is externally founded by its Relator, as required by UFO anti-rigidity rules stated in this ODR.

Capacity split

• opda:assertedCapacity — SKOS-typed (→ ODR-0011).
• opda:evidencedAuthority — link to evidence (→ ODR-0009).
• The founding grant (probate, POA) is modelled as the missing Relator.

Turtle stubs

opda:Person a owl:Class ;
    rdfs:label "Person"@en ;
    ufo:isKind true .

opda:Organisation a owl:Class ;
    rdfs:label "Organisation"@en ;
    ufo:isKind true .

opda:Seller a owl:Class ;
    rdfs:label "Seller"@en ;
    ufo:isRoleMixin true ;
    ufo:foundedBy opda:Transaction .

opda:Proprietor a owl:Class ;
    rdfs:label "Proprietor"@en ;
    ufo:isRole true ;
    ufo:foundedBy opda:Proprietorship .

SHACL constraints (ODR-0013)

SHACL shapes constrain opda:Seller/opda:Buyer role-play to a opda:Person or opda:Organisation bearer, and require an opda:evidencedAuthority link where a capacity is asserted in a regulated context:

opda:SellerShape a sh:NodeShape ;
    sh:targetClass opda:Seller ;
    sh:property [
        sh:path opda:playedBy ;
        sh:or ( [ sh:class opda:Person ] [ sh:class opda:Organisation ] ) ;
        sh:minCount 1 ;
    ] ;
    sh:property [
        sh:path opda:assertedCapacity ;
        sh:node opda:RegulatedCapacityRequiresEvidence ;
    ] .

Enforcement and gates

• Validated against the participant facets of the diagnostic exemplars (ODR-0005): private-individual seller, organisation seller, seller acting under power of attorney.
• Role and capacity SKOS concepts (ODR-0011) carry skos:prefLabel/skos:definition sourced from the business glossary and dct:source back to it.
• Freeze gate: this module’s TBox is not frozen until (a) ODR-0005 clears its identity-criterion gate and (b) the remaining Kind-layer choice (W3C Org vs bespoke opda:) is resolved in council.

Decision rationale

The flowchart traces the three candidate agent-layer approaches through their disqualifying defects to the chosen outcome.