The decisions behind the method

An ontology decision record explains a modelling choice, its scope and its consequences. The adopted OPDA ODRs linked here are normative for how we model within the selected scope. OPDA ADRs establish how that discipline is applied to the property programme. Neither adopting a method nor a successful generator run adopts the meanings in a candidate model.

Local decisions govern; upstream sources explain their provenance

The adopted OPDA records have their own numbers and canonical links. For example, OPDA ODR-0041 governs the role-view modelling pattern. The earlier OPDA ODR-0025 concerns the schema-derived implementation's entailment regime and remains historical context, not the role-view decision. Each adopted record identifies its upstream lineage.

The original 29-record adoption is pinned to upstream revision 67174057e6384b79d0b28b7736fe70a66e112895, inspected read-only on 5 September 2026. The upstream project was not modified. OPDA adopts the selected modelling rules, not that project's business content, process models, architecture or implementation tooling. The local record's scope, rule standing and adopted amendments govern; future upstream amendments are not silently adopted by this page.

ODR-0065 adds the namespace policy on 7 September 2026, from source revision 5e083c3baf6837ab93698d883a6ff01338565bd8. It consolidates the relevant namespace decisions with OPDA context codes and opda.org.uk; it does not migrate the existing corpora. The namespace explainer distinguishes selected policy from current identifiers.

ODR-0046: eight selected concerns, not all fourteen categories

Ontology Modelling Category Framework, originally dated 2 April 2026, is adopted in OPDA's category framework. OPDA's scope retains categories 1, 2, 5, 7, 8, 9, 10 and 11. Original numbers are preserved so the selection can be checked without translating a new numbering scheme.

The eight normative concerns selected for this modelling programme

Category	OPDA record	Concern
1	ODR-0047	Domain structure
2	ODR-0048	Vocabulary and taxonomy
5	ODR-0049	Classification metadata
7	ODR-0050	Validation and constraints
8	ODR-0051	Cross-domain mappings
9	ODR-0052	Provenance and quality
10	ODR-0053	Temporal state and history
11	ODR-0054	Access control and data sensitivity

Categories 3 (process modelling), 4 (service architecture), 6 (governance and compliance as an ontology), 12 (capability and intent), 13 (source mapping) and 14 (data products) are outside this required ontology scope. Excluding a governance ontology does not remove programme governance. Excluding a source-mapping model does not discard historical evidence about an input schema.

The scope and package chapter explains the four dispositions for each concern: model here, reuse shared, boundary contribution or not applicable with reasons. Coverage is a responsibility to assess, not a mandate to manufacture eight separate ontologies.

The rules behind the choices

Read a decision with its amendment and rule-level standing. A document can retain historical wording or contain a separately marked proposal. Its heading alone does not make every paragraph a current normative requirement.

Adopted OPDA contracts, applied only within the selected scope

Concern and records	Required discipline	Explanation
Namespaces and stable identifiers ODR-0065	Use the selected opda.org.uk namespace topology; distinguish vocabulary, instances and documents. Preserve existing corpus identifiers until a separate authorised migration.	Namespaces and identifiers
Boundaries and authority ODR-0038 · ODR-0045 · ODR-0060	Give meaning a coherent, accountable context. Semantic ownership, organisational accountability, classification and system topology are not the same structure.	Strategic context maps
Vocabulary and classification ODR-0036 · ODR-0039 · ODR-0040	Separate classification from inheritance. Govern concepts and labels with SKOS; distinguish closed enumerations, their selected typing pattern, and open populations.	Names, choices and classifications
Identity and property placement ODR-0041 · ODR-0042	Distinguish kind, role and phase. Place applicability at the type that introduces the meaning and represent qualifications explicitly. Class-level roleOf/phaseOf annotations are not instance participation.	Roles and phases
Foundational discipline ODR-0061 · ODR-0062 · ODR-0063	Apply OntoClean and UFO-informed analysis across the selected concerns. Do not subsume domain classes under external upper-ontology classes.	Foundations and modelling judgement
Property applicability ODR-0037	For each subject and value side, select exactly one complete mechanism: a safe universal RDFS declaration, alternative Schema.org inclusion hints, or a governed waiver. Read the 28 and 30 August amendments.	Meaning, checks and delivery
Semantic standards and execution ODR-0043 · ODR-0044	Use RDF 1.2, SPARQL 1.2 and SHACL 1.2 with pinned package profiles and feature evidence. Keep standard RDF/RDFS/OWL semantics. Bound the selected OWL surface; declare SHACL constraints and rule materialisation separately, with traceable derived information.	Languages and profiles
Qualified mappings ODR-0056 · ODR-0058 · ODR-0059	Establish identity compatibility before equivalence. Retain SKOS correspondence statements and qualified SSSOM 1.0 records using SEMAPV process values and named RDF 1.2 reifiers.	Qualified term mappings
Strategic context map records ODR-0064	Keep strategic DDD relationships separate from term mappings. Active AS-IS/TO-BE records reference individual applicable mappings. Preserve the special history boundary rather than applying generic PROV revision predicates.	Strategic context maps
Evidence, time and metadata ODR-0052 · ODR-0053 · ODR-0055	Reuse selected canonical PROV-O, OWL-Time and Dublin Core terms through bounded profiles. Attribution is not truth; a recording date is not automatically the time a fact applies.	Evidence and time
Sensitivity and policy ODR-0054 · ODR-0057	Use local classifications and reviewed DPV mappings. ODRL through its DPV profile is conditional and limited to the selected policy cases; annotations are not access enforcement.	Sensitivity and policy

Amendments that change how older explanations must be read

1. RDFS domain and range are not “OR” documentation

   ODR-0037's 28 August amendment retires the earlier alternative-domain convention. Repeated domains imply membership in all declared classes under RDFS semantics. Disabling local inference does not change that meaning. The 30 August amendment requires complete, exclusive applicability coverage on both sides: a safe universal RDFS IRI, Schema.org inclusion hints for intended alternatives, or a governed waiver.

2. Mappings require records, including internal mappings

   The selected ODR-0056 / ODR-0058 / ODR-0059 contract requires SSSOM 1.0 qualification and SEMAPV matching-process values, with a named RDF 1.2 reifier as well as the retained SKOS assertion. The 30 August profile excludes sssom:author_id; that does not abolish the human decision. An empty current mapping set is an implementation boundary, not a deferral of the normative method.

3. Concern organisation does not displace identity analysis

   ODR-0062 places the concern spine in the organising role while foundational analysis remains cross-cutting. ODR-0063 prohibits external upper-ontology class subsumption within scope. The analytical method and importing an external ontology are different choices.

4. The active context map has a specific history boundary

   ODR-0064 keeps active AS-IS/TO-BE strategic records and links exact applicable mapping records. It does not authorise prov:wasDerivedFrom or prov:wasRevisionOf on ContextRelationship resources. Files and Git retain that history. The general provenance chapter must not override this more specific contract.

5. An accepted document can still contain a proposal

   ODR-0059 includes a separately labelled proposed refinement. Its accepted header does not automatically adopt that refinement. The technical chapters distinguish the current contract from proposed changes rather than voting them into force through prose.

The relevant OPDA ADRs

Programme scope reconciled with the 7 September 2026 clarifications

OPDA record	Standing	What it contributes
0039 · Linked-data foundation	Accepted · 3 June 2026	The semantic foundation and the relationship to delivery representations.
0063 · Domain-led working groups	Accepted · 19 July; clarified 7 September	Practitioner-led meaning within established context boundaries, six outputs and the selected ODR-0046 concerns.
0064 · Modelling website revamp	Accepted · 19 July	Readable participation and explicit candidate-versus-historical authority.
0067 · First-principles Property Pack	Accepted · 3 August	The RDF 1.2, SPARQL 1.2 and SHACL 1.2 baseline with bounded candidate conformance.
0074 · Website information architecture	Implemented · 18 August	One Modelling destination for both audiences, using the shared page and navigation templates. This rewrite organises their tasks into four journeys.
0075 · Property Pack component	Accepted · 19 August	The accelerated Property Pack component is not the entire framework.
0065 · AI-assisted workflow 0068 · Standards lifecycle	Proposed · 19 July / 3 August	Wider operating and promotion proposals. Describing a required modelling method does not make these proposals operative.

How to make a claim readers can check

For a method requirement

Link the adopted OPDA decision and identify its applicable rule or amendment, local standing and scope. Treat its upstream revision as provenance, not a separate source of authority.

For an implementation statement

Name the candidate version, emitted feature, actual check and limitation. A declared prefix is not use of a vocabulary; parsing is not an entailment receipt.

For a teaching illustration

Say that it is fictional, state the assumptions and retain unresolved questions. Do not give invented data the standing of approved OPDA content.

For a proposed operating feature

Label the proposal and the decision still needed. A documentation diagram does not prove that a review or approval service exists.

The language and standards register records external specification maturity, OPDA governance status and candidate implementation independently. Its external publication checks have their own dates; this adoption-provenance review does not refresh them.

Use the legacy PDTF explanations as evidence, not a hidden specification

The legacy modelling explainer and identity guide preserve the reasoning and implementation history of a schema-derived model. Reusable techniques are now re-authored in the foundations, representation and source-evidence chapters. The older business-specific identity choices, technical counts and runtime conventions do not govern the new teaching or silently define the candidate.

In particular, earlier OPDA documentary-domain and SSSOM-deferral accounts remain historical evidence. The adopted OPDA amendments above govern the selected method. This documentation rewrite does not alter the ontology corpus, invent reviewed mappings or claim that an outstanding generator migration has happened.