OPDA Knowledge base
Concept tier agent

Buyer

opda:Buyer

Buyer

A Buyer is the role borne by the party acquiring a Property in a Transaction. Buyer is a Role Mixin: it can be borne by a Person or an Organisation, and it gets its identity from the (Transaction, bearer) pair.

Why it matters

Buyer mirrors Seller: both are Role Mixins founded by the same Transaction. In a chain of transactions, the Buyer of one link is typically the Seller of the next; the Role Mixin pattern handles both perspectives uniformly without splitting into kind-specific role classes.

If you are an integrator working with buyer-side data — affordability claims, lender-attribution, identity-verification claims — this is the entity that links those records back to the underlying Person or Organisation.

Hard cases

  • Chain-overlap. The Buyer in one Transaction is the Seller in the next. Two distinct Role-Mixin instances on one Person — different Transactions, different role-specific properties.
  • Joint Buyers. Two co-purchasers acting together. Two Buyer Role-Mixin instances on the same Transaction, both founded by the same Transaction Relator.
  • A buying Organisation that doesn’t exist yet. A Special Purpose Vehicle (SPV) created for the purchase. The Organisation must exist as a record before the Buyer Role-Mixin can bind to it; the IC won’t accept a Buyer with no bearer.

Identity Criterion

A Buyer Role-Mixin instance is identified by its (Transaction, bearer) tuple — the Transaction context plus the Person or Organisation bearing the role. The Role Mixin NEVER supplies its own identity. See the Logical tier → for the typed structure.

  • Role Mixin — Buyer is the canonical OPDA Role Mixin alongside Seller
  • Seller — the mirror Role Mixin in the same Transaction
  • Person — a typical bearer of the Buyer role
  • Organisation — the alternative bearer
  • Transaction — the Relator within which the Buyer Role Mixin is borne
  • Transaction Chain — chains are built from buyer-also-seller participant overlap
%%{init: {"theme": "base"}}%% flowchart LR accTitle: Buyer related-Kinds neighbourhood graph accDescr: Buyer as a RoleMixin borne by either a Person or an Organisation, founded by a Transaction, mirrored by Seller; the buyer-also-seller overlap is the join into a Transaction Chain. classDef centre fill:#E1BEE7,stroke:#6A1B9A,stroke-width:3px,color:#4A148C classDef cls fill:#B3E5FC,stroke:#0277BD,stroke-width:2px,color:#01579B classDef ext fill:#ECEFF1,stroke:#455A64,stroke-width:2px,color:#263238 Buyer["Buyer
(RoleMixin)"]:::centre Person["Person"]:::cls Organisation["Organisation"]:::cls Transaction["Transaction"]:::cls Seller["Seller
(mirror)"]:::cls Chain["TransactionChain"]:::cls RoleMixin["RoleMixin
(pattern)"]:::ext Buyer -->|"borneBy"| Person Buyer -->|"or borneBy"| Organisation Transaction -->|"founds"| Buyer Buyer -.->|"buyer-also-seller
overlap to next link"| Seller Chain -->|"composed via overlap"| Buyer Buyer -.->|"specialises"| RoleMixin

Source ODR

ODR-0006 — Agents and roles §Q2

Comments

Loading comments…