Land readjustment projects (tochi kukaku seiri jigyō, 土地区画整理事業) are a common feature of urban development and infrastructure improvement in Japan. These projects often involve extensive re-parceling of land to create more regular and usable lots, alongside the establishment of new public facilities such as parks and, crucially, municipal roads (shidō, 市道). The creation of these new roads necessitates their registration as distinct parcels of land, each requiring a unique lot number (chiban, 地番). While the general principles of lot numbering in Japan emphasize sequential assignment, a Ministry of Justice Civil Affairs Bureau directive from July 21, 1961 (Showa 36, Minji Kō No. 1750), provided important clarifications on the flexibility allowed for numbering such public infrastructure within these specially designated zones.

Fundamentals of Lot Numbering (Chiban) in Japan

The Japanese system for assigning lot numbers is designed to ensure that every parcel of land can be uniquely and unambiguously identified. Key principles, historically rooted in the old Land Ledger Act and now found in the Real Property Registration Rules (e.g., Articles 97 and 98) and the Real Property Registration Affairs Handling Procedure Rules (e.g., Article 67), include:

• Unique Identification: Each chiban must be unique within a designated "lot numbering area" (chiban kuiki, 地番区域). This area is typically a subdivision of a municipality, such as an ōaza (大字, large section) or aza (字, smaller section).
• Sequential Assignment: As a general rule, lot numbers are assigned sequentially, starting from 1, within the chiban kuiki.
• Branch Numbers: When a parcel is subdivided (bunpitsu, 分筆), branch numbers (e.g., 100-1, 100-2 or 100番の1, 100番の2) are often used to maintain a connection to the original lot number while ensuring uniqueness for the new parcels.
• No Re-use of Closed Numbers (Generally): To avoid confusion, lot numbers of parcels that have been closed (e.g., due to amalgamation or extinction) are generally not immediately reused.
• Prohibition of "Lot No. 0": A fundamental rule is that lot numbering begins with "1". The use of "0" as a lot number is not permitted.

While these rules provide a framework for order and clarity, the system also acknowledges that "special circumstances" (tokubetsu no jijō, 特別の事情) may warrant deviations from strict sequential numbering.

The Challenge: Numbering Municipal Roads in Reconfigured Land Readjustment Zones

In Japan, public roads, including municipal roads, are typically registered as separate parcels of land in the property registry. Their land category (chimoku, 地目) is designated as "public road" (kōshūyō dōro, 公衆用道路). As registered parcels, they require their own unique chiban.

Land readjustment projects often result in a complete redesign of an area's layout. Existing lot boundaries are extinguished, and new parcels are created for both private use and public facilities. Simply interspersing the lot numbers for new roads within the sequential numbering for new private lots could:

• Make it difficult to quickly distinguish road parcels from private parcels on maps and in records.
• Consume valuable sequential numbers that might be better reserved for the private lots.
• Lead to a less intuitive or organized numbering scheme in the newly planned area.

This context set the stage for the 1961 (Showa 36) inquiry from the Aomori District Legal Affairs Bureau.

The 1961 (Showa 36) Ministry of Justice Directive: A Case for Flexibility

The Aomori Inquiry:
The Aomori District Legal Affairs Bureau was dealing with a land readjustment project where the newly configured private land parcels had been assigned lot numbers from 1 to 35. The project implementer needed a method to assign lot numbers to the newly created municipal roads within this zone.

• Initial Proposal (Lot No. 0): An initial idea, apparently from the project implementer's side, was to assign "Lot No. 0" (〇番) to the municipal roads. However, the Legal Affairs Bureau correctly noted that this approach was improper. A Ministry of Justice Civil Affairs Bureau communication from 1960 (Showa 35, Minji Kō No. 1896) had already established that assigning "Lot No. 0" was not an acceptable practice.
• The Second Proposal (The "100 Series"): Faced with the rejection of "Lot No. 0," a strong request was made for an alternative: to assign lot numbers to the municipal roads starting from 100 (e.g., 100-1, 100-2, 100-3, etc.). This would involve intentionally skipping the lot numbers from 36 to 99, creating a distinct numerical block specifically for the road parcels.

The Ministry's Approval:
The Director-General of the Civil Affairs Bureau, in the reply dated July 21, 1961 (Showa 36, Minji Kō No. 1750), approved this second proposal. The decision affirmed that it was permissible to:

1. Leave a gap in the sequential numbering (numbers 36 to 99 in this case).
2. Assign a new series of numbers (starting from 100) specifically for the municipal roads.

The legal basis for this flexibility was found in the then-applicable Land Ledger Affairs Handling Guidelines (土地台帳事務取扱要領第6第1項6号). This guideline allowed for the assignment of "appropriate lot numbers" (tekigi no chiban) when "special circumstances" (tokubetsu no jijō) existed. The context of a land readjustment project, with its complete reordering of parcels and creation of new public infrastructure, was deemed to constitute such special circumstances.

Rationale for the Flexible Approach to Road Numbering

The 1961 directive highlighted several important considerations:

• Enhanced Clarity and Distinction: By assigning a distinct block of numbers to municipal roads, these public infrastructure parcels become easily distinguishable from privately held lots on cadastral maps and in the land registry. This aids in administrative efficiency for local governments and provides greater clarity for the public.
• Systematic Organization: While deviating from strict sequence, this method still allows for a systematic approach within the designated block (e.g., 100-1, 100-2 for different road sections).
• Preservation of Sequential Numbers for Private Lots: Skipping a range of numbers and using a separate series for roads means that the primary sequential numbering (starting from 1) can be reserved for the newly configured private lots, potentially leading to a more orderly and predictable system for those parcels.
• Practicality for Project Implementers: In complex urban redevelopment schemes, this flexibility allows project implementers and registry officials to devise a numbering plan that is logical and manageable for the specific characteristics of the redesigned area.

The Enduring Prohibition of "Lot No. 0"

It is critical to reiterate that while flexibility is permitted in certain circumstances, the fundamental rule against using "0" as a lot number remains absolute. The 1960 (Showa 35) directive explicitly stated its unsuitability, and this principle is upheld. Lot numbering in the Japanese system inherently begins with the number "1".

Modern Relevance and Alternative Flexible Numbering Methods

The principles underlying the 1961 directive remain highly relevant today. Current Japanese real property registration law, specifically the Real Property Registration Affairs Handling Procedure Rules (不動産登記事務取扱手続準則 - Fudōsan Tōki Jimu Toriatsukai Tetsuzuki Junsoku), Article 67, Paragraph 1, Item (vii), continues to provide for the assignment of "appropriate lot numbers" (tekigi no chiban) when "special circumstances" justify a deviation from standard sequential numbering. The comprehensive replotting involved in land readjustment projects generally qualifies as such a special circumstance.

Furthermore, Article 67, Paragraph 1, Item (viii) of the same Procedural Rules explicitly permits the use of "block (street block) lot numbering" (burokku (gaiku) chiban o fuchishite sashitsukaenai) in areas that have undergone land readjustment. This system might involve assigning numbers like "Block A-1," "Block B-Lot 5," or similar alphanumeric combinations based on newly defined blocks and street layouts. This is another recognized method for achieving clarity and organization in redeveloped urban landscapes and can be seen as an alternative or complementary approach to the "separate numerical series" method approved in the 1961 Aomori case.

The choice of specific numbering method (e.g., skipping a block and starting a new series, or using block numbering) will often depend on the scale and complexity of the land readjustment project, local practices, and consultations between the project implementers and the relevant Legal Affairs Bureau.

Conclusion: Orderly Development Through Flexible Identification

The 1961 (Showa 36) Ministry of Justice directive concerning the lot numbering of municipal roads within land readjustment zones serves as a clear illustration of the Japanese land registration system's capacity for pragmatic adaptation. While upholding the core goals of unique parcel identification and the avoidance of ambiguity (such as prohibiting "Lot No. 0"), the system allows for flexible numbering strategies in complex scenarios like large-scale urban redevelopment.

By permitting deviations such as assigning distinct numerical series or employing block-based numbering for public infrastructure, the registry facilitates clearer administration and public understanding of newly configured areas. This balanced approach ensures that the chiban system, while rooted in fundamental principles of order and sequence, can effectively support the dynamic processes of urban planning and infrastructure development in Japan.