What Is a Contract?
A contract is a formal document that sets out rights and obligations between parties.
Common examples include:
- sales agreements
- outsourcing agreements
- lease agreements
- non-disclosure agreements (NDAs)
The purpose is to prevent disputes, clarify responsibility, and preserve evidence.
Contracts usually define items such as:
- purpose of the agreement
- contract period
- compensation
- payment terms
- damages
- termination conditions
Article 1 Purpose
Article 2 Scope of Work
Article 3 Compensation
Article 4 Contract Period
...Contracts tend to be comprehensive.
What Is a Memorandum?
A memorandum is a document used to confirm, supplement, or amend agreed matters.
It is often used when an existing contract is already in place and the parties want to change only part of it, such as:
- price changes
- contract extensions
- additional terms
Example:
Original contract:
Contract period: January 2025 to December 2025
Memorandum:
The contract period is extended to December 2026.In this way, a memorandum can amend only a specific part of the original contract.
Is the Legal Effect Different?
In many cases, a memorandum can also have legal effect.
Under Japanese civil-law practice, what matters is whether there is an agreement between the parties and whether the content is sufficiently clear.
Even if the title is:
- Contract
- Memorandum
- Agreement
- MOU
the document may be legally effective if the agreement is clear.
Main Differences
| Item | Contract | Memorandum |
|---|---|---|
| Main use | New agreement | Supplement or amendment |
| Scope | Comprehensive | Specific matters |
| Length | Often longer | Often shorter |
| Legal effect | Yes | May have legal effect |
| Practical role | Main document | Supporting document |
Practical Points to Check
1. Relationship with the original contract
A memorandum should usually state that it amends or overrides the relevant part of the original contract.
This memorandum shall amend the original agreement.Without this, interpretation can become unclear.
2. Signature or seal
Even for a memorandum, it is common to use:
- signatures
- name and seal
- electronic contract procedures
3. Document management
In practice, memoranda can accumulate over time.
Original contract
↓
Memorandum 1
↓
Memorandum 2
↓
Memorandum 3If many changes are made, it may be cleaner to create a new contract rather than adding more memoranda.
Example in Real Estate
In real estate, including fixed-term land lease contracts, parties may later need to adjust:
- ground rent
- contract period
- management rules
In such cases, a memorandum is often used instead of drafting an entirely new contract.
What Investors Should Know
Corporate IR materials sometimes mention a "memorandum" or "MOU" such as:
- business alliance memorandum
- basic agreement memorandum
- Memorandum of Understanding
However, a memorandum does not always mean that a binding contract has already been concluded.
In M&A or business alliance situations, it may only cover:
- basic intent
- exclusive negotiation rights
- non-binding discussions
For investment decisions, check whether the memorandum is legally binding and what obligations are actually created.
Conclusion
The difference between a contract and a memorandum is mainly practical use. A contract usually sets out a new agreement, while a memorandum often supplements or amends an existing contract. Legal effect depends on content, not the title. In business, real estate, and IR disclosures, it is important to read what has actually been agreed and whether it is binding.