B2B Maintenance Obligations and the A/B/C 'Kouji' Demarcation

In residential apartments, a landlord's duty to fix broken air conditioners and water heaters is absolute. Contrastingly, in the high-stakes world of Osaka’s massive commercial office floors and retail spaces, landlords violently push almost 100% of the maintenance, utility infrastructure, and repair costs directly onto the corporate tenant. This is achieved via ruthless lease clauses and the notorious Japanese "Kouji Demarcation" system.

Disclaimer: This guide provides general legal information for educational purposes only and does not constitute legal advice. Disputes over commercial maintenance and contractor selection involve multi-million yen risks. Always seek advice from a Japanese attorney and a First-Class Certified Architect. Last verified: March 2026.

Passing the Buck: B2B Cost Allocation

While Article 606 of the Civil Code states that "A lessor shall assume the obligation to effect repairs necessary for the use and profit of the leased thing," this is merely an "optional" regulation in B2B leases. In a commercial environment, "Freedom of Contract" dictates that landlords can legally overwrite this rule.

Landlord Responsibility (The Building Core)

The landlord's financial and maintenance burden is strictly limited to the structural core (Kutai) and common facilities.

• The foundation, exterior walls, and roof waterproofing.
• Building-wide elevators, first-floor lobbies, main water pumps, and the primary electrical substation room.

Tenant's Responsibility (The Exclusive Leased Space)

A commercial lease’s Special Clauses dictate that any maintenance, equipment replacement, or statutory safety inspections that occur inside the tenant's rented walls are exclusively paid for out of the tenant's pocket.

• All interior walls and networking cables.
• The massive commercial HVAC units servicing only their floor.
• Clogged plumbing inside their restaurant kitchen or office bathrooms.
• Even if the tenant moves into an "Inuki" (Turnkey) space and inherits an old air conditioner from a previous renter, the landlord claims complete immunity; if it breaks on day one, the new tenant must buy a $30,000 replacement themselves.

The Chaos Agent: "The Demarcation System" (A/B/C Kouji)

When a massive corporation moves into a Osaka skyscraper, they must spend hundreds of millions to build out their office. The greatest battleground between a tenant wanting to save money, and a landlord desperate to protect their building's structural integrity, is Japan’s "Kouji Demarcation" (Kouji Kubun) system.

1. A-Kouji (A-Work):
   • Cost Burden: Landlord
   • Contractor: Landlord’s Designated Mega-Construction Firm (Zenekon)
   • Repairs to the building's core exterior, elevators, or shared lobbies. The tenant does not pay for this.
2. B-Kouji (B-Work): 【The Ultimate Flashpoint】
   • Cost Burden: Tenant (Out of Pocket)
   • Contractor: Landlord’s Designated Mega-Construction Firm (Exclusively)
   • This is the source of endless corporate warfare in Japan. B-Kouji involves work that occurs inside the tenant’s private office but heavily interconnects with the building's central life-safety or utility systems—such as relocating fire sprinklers, altering central HVAC ducts, or pulling massive power lines from the basement substation.
   • The Conflict: Because B-Kouji affects the whole building's safety, the landlord legally forces the tenant to use the landlord's designated mega-contractor. The tenant is trapped; they cannot ask for competitive quotes. Consequently, the designated contractor often gouges the tenant, presenting quotes that are 3 to 5 times the market rate. The Property Manager (PM) must utilize immense diplomatic skill to negotiate these inflated quotes down to prevent the tenant from abandoning the lease entirely.
3. C-Kouji (C-Work):
   • Cost Burden: Tenant (Out of Pocket)
   • Contractor: Any Contractor the Tenant Chooses
   • Cosmetic, superficial work that does not touch the building’s core infrastructure: laying carpets, painting walls, installing independent desks, or hanging custom lighting. Tenants are free to hire the cheapest crew they desire.

2020 Civil Code: The Terror of the B2B "Self-Repair" Right

Before 2020, if an Asset Manager ignored a tenant’s plea to fix an A-Kouji structural issue (like a leaking roof), the corporate tenant was legally forbidden from touching the landlord’s building.

The 2020 Civil Code revision dramatically changed this power dynamic. Article 607-2 granted all tenants—even mega-corporations leasing 10 floors of an office building—the Right to Unilateral Self-Repair.

The Multi-Million Yen Threat

Imagine an office ceiling (a structural A-Kouji component) springs a massive leak, threatening the tenant’s $5 million server racks. The tenant urgently notifies the PM, but the landlord’s side stalls for a few weeks to get cheaper quotes.

Under current Japanese law, the corporate tenant can legally hire a contractor themselves immediately, authorizing an emergency 50,000,000 JPY roof repair without the landlord's permission.

The Financial Impact (Articles 608 & 611):

1. Reimbursement & Offset: The tenant has the immediate legal right to demand the 50,000,000 JPY from the landlord. If the landlord argues, the tenant can legally enact an offset (Sausai), unilaterally deciding to withhold 100% of their rent payments for the next few months until the 50 million is perfectly recuperated.
2. Automatic Rent Reduction: Furthermore, if the leak rendered 20% of the office space unusable, the law states the rent is automatically reduced by 20% for those weeks.

"Taking our time" to fix structural A-Kouji issues in B2B leases is no longer a lazy annoyance; it is a deadly trigger that gives corporate tenants the legal weapon to instantly freeze a landlord's multi-million dollar cash flow.

Landager utilizes high-priority A/B/C Kouji legal tags on all corporate ticketing. Any ticket flagged as "A-Kouji" (Landlord liability) involving critical infrastructure instantly bypasses standard queues and triggers SLAs with mega-contractors. This establishes a legally auditable timestamp of "rapid landlord response," completely blockading malicious corporate tenants attempting to exploit the Civil Code’s "Self-Repair and Rent-Offset" mechanics.

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