Co-ownership and redevelopment decisions

When a Japanese property is held by more than one person, the first question is not “can we redevelop?” but “who actually holds which right over which parcel or building, and what does the current register say?” The answer is rarely visible from a single document. Official records are fragmented across local Legal Affairs Bureaus (法務局), municipal planning departments, and archived corporate registries, and there is no unified national portal for private use. Before treating consent as available, you need a method that maps shares, decision rights, unresolved succession, and professional questions in a fixed order.

This article is written for investors, tenants, heirs, and advisers who need to locate and interpret Japanese property records. It does not replace a licensed professional’s advice on your specific project.

Why co-ownership blocks redevelopment

A redevelopment project usually requires the consent of every co-owner of the land and building. Under Japanese law, the key threshold is found in Article 14 of the Urban Redevelopment Act (都市再開発法), administered by the Ministry of Land, Infrastructure, Transport and Tourism Japan (MLIT). For certain redevelopment procedures, a co-owner or landowner whose share exceeds a statutory ratio can apply for a decision that overrides objecting minority owners. The exact ratio depends on the project type and the applicable ordinance, and it has changed over time; you must check the current text of the Act on e-Gov Japan before relying on any number. The point is not to quote the ratio from memory, but to show how to verify it from primary records.

Do not assume that a co-owner’s share in a building equals their share in the land. In Japanese real estate, the land register (登記簿) records the land parcel and each co-owner’s undivided share. The building register records the building as a separate asset. A person can own 50% of the land and 0% of the building, or the reverse, if the building was constructed under a different ownership arrangement. The first step in any redevelopment decision is to map both registers, not just the one that looks relevant.

What counts as a co-ownership decision

A co-ownership decision is any decision that changes the legal or physical status of a parcel or building that has more than one registered owner. That includes:

• Selling the whole property
• Mortgaging the property
• Demolishing and rebuilding (建替え)
• Redevelopment under the Urban Redevelopment Act (都市再開発法)
• Changing the building’s use, floor area, or structure
• Granting or releasing an easement
• Subdividing or merging parcels

The critical point: the number of co-owners is not the same as the number of people who must agree. Some co-owners may have died without probate, some may be minors, and some may hold only a paper interest with no recorded address. The register tells you who holds the right, not who can validly consent.

A method for mapping ownership before consent

1. Start with the current register, not the story

The official record is the land register (登記簿, tōkibo) held at the Local Legal Affairs Bureau (法務局) that has jurisdiction over the parcel. The register is the only reliable starting point for ownership. A sale contract, a family statement, or an archived project memo is evidence of a claim, not proof of a right. The register shows the current owner, the share held by each co-owner, and the encumbrances recorded against the parcel. It does not, however, show every interest that affects the land. Easements, leasehold interests, and restrictions created by private agreement may appear in the register or may be recorded elsewhere.

To request the record, use the parcel’s land registration number (地番) and locate the file at the Legal Affairs Bureau (法務局) that has jurisdiction over the property’s location. The official register is called the 登記簿 (tōkibo). The accompanying cadastral map is the 地図 (chizu). These are separate records. Do not assume the map and the register match. Boundary lines on older cadastral maps can carry positional errors of several metres, and the register does not guarantee the physical location of the boundary. A licensed land and building surveyor (土地家屋調査士) conducts the boundary survey and prepares the registry application; a judicial scrivener (司法書士) handles the registration filing. For project-specific questions, consult a licensed Japanese professional.

2. Map both land and building shares separately

A co-owner’s share in the land and their share in the building are recorded on different registers. Request both documents and compare them side by side. List every registered co-owner, their stated share, and the date of registration. Flag any mismatch between the two registers. A person listed on one but not the other still holds a right that may block consent.

3. Identify gaps that block valid consent

Work through this checklist for every co-owner on the register:

• Is the co-owner still alive? If not, has probate (相続登記) been completed and recorded?
• Is the co-owner a minor or an adult ward? If so, who holds legal authority to consent?
• Does the register show a current address for the co-owner? An outdated or missing address often signals an unadministered estate.
• Are there registered encumbrances, such as mortgages or attachments, that restrict the co-owner’s ability to act alone?
• Does the building register show a leasehold interest (借地権 or 借家権) that survives a sale or demolition?

Each “no” or “unclear” answer is a block to consent. Resolve it before counting the share toward any statutory threshold.

4. Know which records sit outside the register

Not every interest that affects redevelopment appears on the land or building register. Check these sources separately:

• The Fixed Asset Tax Register, maintained by the municipality, not the Legal Affairs Bureau. It may reveal beneficial ownership or use patterns that the legal register does not.
• The cadastral map (地図), which shows parcel boundaries. The National Land Numerical Information (国土数値情報) provides MLIT’s digital GIS layers for zoning and land use.
• Municipal planning department records for zoning, district plans, and redevelopment promotion areas.
• Archived corporate registries when a co-owner is a dissolved company.

5. Understand the legal framework that sets the rules

Several statutes interact on any redevelopment project. Knowing which one governs your question prevents costly assumptions:

• The Urban Redevelopment Act (都市再開発法) sets the framework for coordinated redevelopment projects, including the consent thresholds in Article 14.
• The Land and Building Leases Act (借地借家法) governs lease protection and renewal rights. A sitting tenant under a protected lease cannot be ignored just because the building register lists a different owner.
• The Building Standards Act sets structural and fire-safety rules. The 1981 revision introduced revised seismic design standards. The 2006 revision introduced a structural review system for specified buildings. A building confirmation application (建築確認申請) is filed with the local government, and the approval may lapse if construction does not start within the statutory period.

6. Know when to stop and bring in a professional

A licensed land and building surveyor (土地家屋調査士) handles boundary surveys and registry applications. A judicial scrivener (司法書士) handles registration filings. When the register shows an unresolved estate, a missing co-owner, or a boundary that does not match the cadastral map, stop. The next step is a licensed Japanese professional, not further desk research.