Australian Property Investment, Accommodation and Operations Ontology (pbo)

Status: release_candidate (version 0.1.0, 2026-09-14). All mandatory deterministic gates, the 15 competency-question tests and SHACL conformance (pySHACL, RDFS inference) pass. No OWL DL reasoner has been run; the release policy does not require one.

Ontology IRI https://ontology.property.local/pbo · prefix pbo: · base https://ontology.property.local/pbo# · licence CC-BY-4.0 · creator Ryan Ballantyne.

What it models

An evidence-first ontology derived from the property-pages corpus: 31 scraped web sources, seven category summaries, seven combined source references and two deep-research reports, all compiled 14 September 2026. The model covers:

• Property assets and identifiers – land parcels, buildings, dwellings, rentable units, commercial premises; address, lot-on-plan, cadastral parcel and title reference.
• Parties and roles – persons, organisations, government bodies, councils, regulators and businesses bearing roles (owner, investor, operator, provider, landlord, tenant, resident, owner-occupier, property manager, lender, insurer, developer, adviser, corporate tenant, anchor tenant) through a participation node.
• Agreements – residential tenancy, rooming accommodation agreement, head/master lease, sublease, management agreement, corporate lease, commercial lease, clauses (subletting permission, co-tenancy) and outgoing allocations by lease type.
• Accommodation and operating models – whole-dwelling rental, rooming house / HMO / boarding house / share house, purpose-built studios, coliving, dual-income configurations, short-stay, corporate furnished, single- and multi-tenant commercial; owner-operated, master lease / rent-to-rent, management / revenue share, hybrid / franchise, corporate leasing, owner-occupier rooms, short-stay.
• Strategies and structures – 15 investment strategies; individual, joint tenants, tenants in common, discretionary trust, unit trust, company and SMSF with sourced characteristics.
• Regulation – regulatory regimes with jurisdiction, legislation, regulator, occupancy thresholds (kind, comparator, value, effect), required authorisation types, dated rules and tax rules; authorisations with status and validity (planning, building, fire, QLD residential-service registration and accreditation, VIC operator licence and premises registration, agent licence).
• Finance – financial scenarios with assumption and result metric values; quantitative source claims preserved as competing metric values with authority, jurisdiction and date.
• Risk and decision – risks by category, mitigations and the four rooming-house acquisition gates.
• Business planning and operations – business plan, project plan, feasibility study, information memorandum, financial model, risk register, implementation schedule and their recommended sections; property-management services, fee models, workflows and KPIs; agency business models and capability sourcing.
• Data sources – open, public-paid, commercial and first-party datasets with the property attributes they supply, refresh cadence and licence.

What it explicitly does not model

Statutory text and planning-scheme codes; conveyancing mechanics; construction engineering; personal financial or legal advice and lender products; market statistics as time series; non-Australian legal regimes (kept only as source context); marketing content; strata governance beyond the recorded short-stay restriction; HR and general accounting practice. See requirements.yaml for the full exclusion list.

Intended use

Primary: AI grounding. Secondary: retrieval and cataloguing, integration with the planned property-intelligence platform, SHACL validation of stored records. OWL 2 DL is used for structure and disjointness, but no core competency question depends on entailment.

Bundle layout

Regenerating and validating

python3 build/build_model.py && python3 build/build_evidence.py
python3 ../ontology-v1.1/scripts/validate_project.py . --json validation/validation.json
python3 ../ontology-v1.1/scripts/run_cq_tests.py . --json validation/cq-results.json
uv run --with pyshacl --with rdflib --with pyyaml python3 ../ontology-v1.1/scripts/run_shacl.py . --json validation/shacl-results.json --inference rdfs
python3 ../ontology-v1.1/scripts/validate_atlas.py . documentation/semantic-atlas.md --json validation/atlas-validation.json

Edit build/build_model.py rather than model.yaml, ontology.ttl or taxonomy.ttl.

Core competency questions

CQ-001 required authorisations per operating model and jurisdiction · CQ-002 occupancy thresholds and effects · CQ-003 roles and risk allocation under agreements · CQ-004 scenario assumptions and results · CQ-005 ownership structure characteristics · CQ-006 strategy to accommodation type / operating model / segment · CQ-007 risks and mitigations · CQ-009 data sources per attribute · CQ-011 provenance of quantitative claims. Supporting: CQ-008, CQ-010, CQ-012 to CQ-015.

Standards and reuse

RDF 1.1, Turtle 1.1, RDFS 1.1, OWL 2 DL, SKOS 2009, SHACL 2017, SPARQL 1.1. PROV-O (prov:Agent, prov:Entity, prov:Activity), SKOS and Dublin Core Terms are referenced by IRI without owl:imports. schema.org, W3C ORG, GeoSPARQL and ELI alignments are recorded as proposed skos:closeMatch / rdfs:seeAlso candidates only.

What remains unresolved

See model.yaml → unresolved_issues. The material ones:

• ISSUE-001/002/003 – rooming-house yield, vacancy behaviour and coliving break-even figures conflict across sources; preserved as competing metric values, never reconciled.
• ISSUE-004 – "rooming house" is defined differently by source and jurisdiction (four or more unrelated tenants; four or more residents paying separately; five lets and 300 m²; nine bedrooms / 12 persons / 300 m²). Thresholds are modelled per regime.
• ISSUE-005/006 – regulatory and tax detail from the deep-research report (QDC MP 5.7, accreditation levels, Clause 52.23 limits, the 1 July 2027 negative-gearing and CGT reform and 12 May 2026 cut-off) is cited through unresolvable tokens and is not independently verifiable from the corpus. Evidence records carry an explicit verification flag.
• ISSUE-010 – seven manifest URLs failed to scrape, so Victorian coliving economics and multi-lease lending are under-represented.
• The .local namespace must be replaced by a persistent IRI before any released version (DEC-010).

Citation

Ballantyne, R. (2026). Australian Property Investment, Accommodation and Operations Ontology, version 0.1.0, https://ontology.property.local/pbo/0.1.0. Derived from the property-pages corpus compiled 14 September 2026. Corrections require a new version; released artefacts are immutable.