The inheritance of real property in Japan, including condominium units, is governed by the Civil Code (民法 - Minpō) and involves specific registration procedures under the Real Property Registration Act (不動産登記法 - Fudōsan Tōki Hō). When the inherited property is a "shikiken-tsuki kubun tatemono" (敷地権付き区分建物) – a condominium unit with legally integrated site-use rights – special attention must be paid to how the "principle of integration" or "inseparability" (一体性の原則 - ittaisei no gensoku) interacts with the laws of succession, particularly in scenarios involving multiple heirs and subsequent estate division agreements (遺産分割協議 - isan bunkatsu kyōgi).

This article explores the legal framework governing the inheritance of such integrated condominium properties in Japan, focusing on the application of the inseparability principle and the required registration processes.

Inheritance in Japanese Law: A Universal Succession

Under the Japanese Civil Code, inheritance (相続 - sōzoku) commences upon the death of the decedent (被相続人 - hisōzokunin) (Civil Code Art. 882). The heir(s) (相続人 - sōzokunin) comprehensively succeed to all rights and obligations that belonged to the decedent's property at the time of death, unless they are strictly personal to the decedent (Civil Code Art. 896). This is a form of "universal succession" (包括承継 - hōkatsu shōkei), meaning the entire estate passes to the heir(s) by operation of law, rather than through specific itemized transfers.

This automatic succession is a key point: the initial passing of property to heirs is not considered a "disposition" (処分 - shobun) in the volitional, transactional sense (like a sale or gift by the deceased during their lifetime). This distinction is crucial when considering the application of specific rules from the Act on Unit Ownership of Buildings (建物の区分所有等に関する法律 - Condominium Ownership Act).

Inheritance and the Principle of Inseparability (Condominium Ownership Act Art. 22)

Article 22, Paragraph 1 of the Condominium Ownership Act establishes the fundamental principle that an exclusive-use unit (専有部分 - sen'yū bubun) and its associated site-use right (敷地利用権 - shikichi riyōken) generally cannot be disposed of separately, unless the condominium's bylaws (規約 - kiyaku) provide otherwise. This is the "principle of integration" or "prohibition of separate disposition."

1. Non-Applicability of Art. 22 to the Act of Succession Itself:
Because inheritance is a universal succession by operation of law and not a volitional "disposition" by the decedent in the manner Article 22 primarily addresses (such as a sale), the initial act of the integrated shikiken-tsuki condominium unit passing to the heir(s) is generally not considered to violate the prohibition on separate disposition. The property, as an integrated whole (unit plus shikiken), simply vests in the heir(s).

2. Integrated Property Remains Integrated in the Hands of Heirs:
If there is a single heir, they inherit the complete shikiken-tsuki unit. If there are multiple heirs (e.g., a spouse and children), they become co-owners (共同相続人 - kyōdō sōzokunin) of this integrated property interest. Their respective shares in this co-owned integrated property are determined by the statutory inheritance shares (法定相続分 - hōtei sōzoku-bun) stipulated in the Civil Code (e.g., Art. 900), unless a will dictates otherwise. The unit and its appurtenant shikiken do not become legally separated merely because they are now co-owned by multiple heirs; they are co-owners of the single, integrated right.

The Critical Role of Estate Division Agreements (遺産分割協議 - Isan Bunkatsu Kyōgi)

While the initial vesting of the inherited property in the co-heirs does not violate the inseparability principle, the situation changes if the co-heirs decide to formally divide the inherited assets amongst themselves. This is typically done through an "estate division agreement" (遺産分割協議 - isan bunkatsu kyōgi), as provided for in Civil Code Article 907.

1. Estate Division Agreement is a Legal Act Subject to Integration:
An estate division agreement is a volitional legal act (法律行為 - hōritsu kōi) by the co-heirs. Through this agreement, they actively decide how to allocate specific inherited assets. Because this involves the "disposition" of property rights among themselves, the Principle of Integration under Article 22 of the Condominium Ownership Act does apply to the terms of an isan bunkatsu kyōgi when it involves a shikiken-tsuki condominium unit.

2. Mandatory Allocation of Unit and Shikiken Together:
This means that when co-heirs are dividing an estate that includes a shikiken-tsuki condominium, their agreement must allocate both the physical condominium unit and its inseparable shikiken to the same heir or the same group of heirs (who would then co-own that specific unit and its shikiken).

• It is legally impermissible for an estate division agreement to, for instance, allocate the condominium unit to Heir A and the shikiken (the underlying land right) to Heir B. Such a provision attempting to sever the integrated rights would be considered void as it directly contravenes the prohibition on separate disposition.
• The goal is to ensure that whoever ends up with the unit also has the legal right to use the land, maintaining the integrity of the shikiken system.

3. Court-Mediated Division of Estate (遺産分割の審判 - Isan Bunkatsu no Shinpan):
If co-heirs cannot reach an agreement, they can apply to the family court for a division of the estate. While a judicial decision itself is not a "disposition" by the parties in the same vein as a contract, legal commentators note that it is practically inconceivable that a court, aware of the Condominium Ownership Act, would issue an order that separates a unit from its shikiken, as this would create a legally problematic property status.

Registration of Ownership Transfer by Inheritance (相続による所有権移転登記)

Once the heir(s) are determined (either by statutory rules or by an estate division agreement that respects the integration principle), the transfer of ownership must be registered in the property register.

1. Sole Application by Heir(s):
Under Article 63, Paragraph 2 of the Real Property Registration Act, an application for registration of an ownership transfer due to inheritance can be made solely by the heir(s) who are acquiring the right. This is a form of registration by the rights-acquirer alone, and the participation of an estate administrator or executor is not generally required for the application itself unless specific circumstances (like a will appointing an executor with powers over property disposition) dictate otherwise.

2. Registration is Made for the Condominium Unit:
The application for the ownership transfer by inheritance is filed specifically for the condominium unit.

3. Automatic Legal Effect on the Shikiken (RPRA Art. 73(1)):
This is a crucial aspect of the shikiken system. When the ownership transfer due to inheritance is registered in the Kō-ku (ownership section) of the condominium unit's registration record, this single registration automatically extends its legal effect to the integrated shikiken.

• The heir(s) are thereby also recognized and perfected as the new holder(s) of the shikiken without any need for a separate registration action on the land records specifically for the shikiken component.

4. No Separate Shikiken Transfer Registration in Land Records (RPRA Art. 73(2)):
Complementing the above, Article 73, Paragraph 2 of the RPRA explicitly prohibits making a separate registration in the land records for the transfer of the shikiken alone when it's part of an integrated shikiken-tsuki unit.

• The public notice (公示 - kōji) and legal effect for the transfer of the shikiken component are achieved entirely through the ownership transfer registration made on the unit's record. This prevents conflicting or redundant entries, keeps the land registry cleaner, and reinforces the legal concept of the unit and its shikiken as a single, indivisible property interest for transactional purposes.

5. Documentation Required for Inheritance Registration:
The specific documents required for registering an ownership transfer by inheritance typically include:

• Family Register Excerpts (戸籍謄本 - koseki tōhon, 除籍謄本 - joseki tōhon, 改製原戸籍 - kaisei genkoseki): These are official documents that prove the death of the decedent and trace their lineage to identify all legal heirs according to the Civil Code. A complete set tracing back to the decedent's birth (or a certain point in time) is often required.
• Certificate of Division of Estate (遺産分割協議書 - isan bunkatsu kyōgi sho): If the co-heirs have entered into an agreement to allocate the condominium unit to a specific heir(s), this agreement is a vital document. It must be executed by all co-heirs and usually requires their registered seals (実印 - jitsuin) to be affixed, accompanied by their individual Seal Certificates (印鑑証明書 - inkan shōmeisho) issued within the preceding three months.
• Certificates of Residence (住民票の写し - jūminhyō no utsushi): For the heir(s) who will be registered as the new owner(s), to confirm their current address for the registry.
• Fixed Asset Valuation Certificate (固定資産評価証明書 - kotei shisan hyōka shōmeisho): Often required for calculating the registration license tax.
• Other documents as may be required by the specific Legal Affairs Bureau or the complexity of the inheritance (e.g., a will, if one exists and is being probated).

Testamentary Gifts (遺贈 - Izō)

A testamentary gift, or izō, is a gift of property made through a will, taking effect upon the testator's death (Civil Code Art. 964). This is considered a unilateral legal act of disposition by the testator.

• As such, the Principle of Integration (COA Art. 22) applies directly. A testator cannot validly bequeath a shikiken-tsuki condominium unit to one beneficiary and its associated shikiken to another beneficiary. The testamentary gift must encompass the integrated property as a whole to be valid with respect to the shikiken rules. If a will attempts such a separation, that aspect of the bequest would likely be deemed invalid.

Comparison with Corporate Mergers (法人の合併 - Hōjin no Gappei)

The PDF chapter also briefly touches upon corporate mergers as another form of universal succession. When a company owning a shikiken-tsuki condominium unit is merged into another company (or two companies merge to form a new one), the surviving or new company succeeds to all assets and liabilities of the merged company by operation of law.

• The shikiken-tsuki condominium, as an integrated property, passes to the successor company.
• The registration of this transfer due to merger also follows the principles applicable to universal successions, primarily requiring official documentation proving the merger (e.g., the merger agreement, corporate registration certificates showing the merger).
• The principle of inseparability of the unit and shikiken continues to apply to the property in the hands of the successor company. The registration on the unit's record will effect the change for the shikiken as well.

Conclusion

The inheritance of a shikiken-tsuki condominium unit in Japan results in the integrated property interest (the unit and its inseparable site-use right) passing to the heir(s) as a unified whole. The act of statutory succession itself does not breach the fundamental principle of inseparability enshrined in the Condominium Ownership Act.

However, if co-heirs subsequently decide to divide the inherited assets through an estate division agreement (isan bunkatsu kyōgi), this agreement is subject to the inseparability principle. Therefore, such an agreement must allocate both the condominium unit and its corresponding shikiken to the same heir or group of heirs to be valid.

The registration process reflects this legal reality: the ownership transfer due to inheritance is registered against the condominium unit, and this single registration automatically and effectively perfects the transfer of the shikiken as well. No separate registration for the transfer of the shikiken is made or permitted in the land records. This system ensures legal clarity, simplifies registration, and consistently upholds the core concept of integrated property rights that defines shikiken-tsuki condominiums in Japan, even through the complexities of generational transfers.