5 Company Naming Mistakes That Block Registration

Your Company Name Can Get Your Registration Rejected

You have chosen the perfect company name. It reflects your brand, sounds professional, and your co-founders love it. You file your registration at the Legal Affairs Bureau — and it comes back rejected.

The Commercial Registration Act (商業登記法) and the Companies Act (会社法) impose specific rules on company names (商号). Violating these rules is not a matter of preference — it is a legal rejection that costs you time and, if you need to re-file, potentially additional fees.

Here are the five most common naming mistakes that block registration in Japan.

Mistake 1: Missing the Required Entity Suffix

Under Article 6 of the Companies Act, a Kabushiki Kaisha must include "株式会社" in its name, and a Godo Kaisha must include "合同会社." You cannot register "MmowW" — it must be "株式会社MmowW" or "MmowW株式会社." This requirement is absolute and has no exceptions.

Mistake 2: Using Prohibited Characters

The Legal Affairs Bureau limits the characters permitted in company names. Permitted characters include kanji, hiragana, katakana, romaji (alphabet), Arabic numerals, and a limited set of symbols (ampersand, apostrophe, comma, hyphen, period, middle dot). Characters outside this set — including most special symbols, emojis, and certain punctuation marks — will cause rejection.

Mistake 3: Including Misleading Terms

Article 8 of the Companies Act prohibits using a name that misleads the public into believing the company is a different type of entity. For example, a GK cannot include "株式会社" in its name, and no company may use terms like "銀行" (bank) unless it is actually a licensed bank under the Banking Act.

Mistake 4: Identical Name at the Same Address

Under the Commercial Registration Act, you cannot register a company with the same name at the same registered address as an existing company. This is not a nationwide uniqueness requirement — two companies can share the same name if they are at different addresses — but if your registered address is in a shared office space, this rule becomes practically relevant.

Mistake 5: Names That Infringe Trademarks or Unfair Competition Laws

While the Legal Affairs Bureau does not conduct trademark searches during registration, choosing a name that infringes an existing trademark exposes you to legal action under the Trademark Act (商標法) or the Unfair Competition Prevention Act (不正競争防止法). This does not block registration itself, but creates legal liability after formation.

Check Your Name Before Filing

MmowW's Company Name Availability Checker helps you avoid all five mistakes. Enter your proposed name, and the tool screens for character compliance, entity suffix requirements, and naming rule violations.

How It Works

1. Enter your proposed company name — In Japanese, English, or a combination.
2. Select your entity type — The tool checks for the correct entity suffix.
3. Review the screening results — The tool identifies character violations, missing suffixes, and potential conflicts.
4. Adjust and re-check — Modify your name and run the check again until you have a compliant name.

Key Benefits

• Prevents the most common rejection cause: Naming violations are among the most frequent reasons for registration rejection at the Legal Affairs Bureau.
• Character validation: The tool checks every character against the permitted set, catching issues that are invisible to the untrained eye.
• Entity suffix verification: Ensures your name includes the required legal designation.
• Instant results: No waiting for a professional review — know immediately whether your name complies.

Real Scenarios

Tech startup using an English name: "TechFlow" sounds clean, but the founder forgot to include "合同会社" for GK registration. The checker flags the missing suffix immediately.

Restaurant choosing a creative Japanese name: "食楽亭＆Bar" uses a full-width ampersand, which may cause issues depending on the character encoding accepted by the Legal Affairs Bureau. The checker validates the specific characters used.

Consulting firm inadvertently using a bank-related term: "Financial Trust Consulting 株式会社" — the checker notes that while "Trust" may be acceptable in English context, the Japanese equivalent could trigger scrutiny under Article 8.

FAQ

Q: Can I use a completely English name for my Japanese company?

A: Yes, romaji (Latin alphabet) is permitted in company names. However, you must still include the entity type designation — either in Japanese (株式会社/合同会社) or in the registered form.

Q: Is my company name protected nationwide once registered?

A: Registration does not grant nationwide name exclusivity. Protection comes from trademark registration (under the Trademark Act) or through unfair competition claims (under the Unfair Competition Prevention Act). The checker helps with registration compliance; trademark protection is a separate matter.

Q: Can I change my company name after registration?

A: Yes, through a name change registration at the Legal Affairs Bureau. This requires a special resolution and a registration tax of ¥30,000.

Try It Now — Free, No Signup Required

Check your company name in seconds:

Use the Company Name Availability Checker →

What's Next?

Name confirmed. Now file it. MmowW Scribe handles the rest — articles of incorporation, registration, and all supporting documents.

Loved for Safety.

Ready to file with confidence? MmowW Scribe guides you step by step — ¥22,000/month.

Start with MmowW Scribe →

Loved for Safety.