Beyond Nice Classes: How Similarity Group Codes Determine Goods Overlap

Foreign applicants filing trade marks in Japan often assume that the Nice Classification governs how goods and services are compared for similarity. It does not. Japan uses the Nice Classification for organisational purposes, but relies on its own Similarity Group Code system to determine whether goods or services are similar. This mechanical system operates very differently from the case-by-case analysis used in the EU and US, and understanding it is essential for effective trade mark protection in Japan.

How the System Works

Every designated good and service in the JPO’s Examination Guidelines for Similar Goods and Services is assigned a Similarity Group Code — typically a five-character alphanumeric code. The fundamental rule is:

• Goods or services sharing the same code are presumed similar.
• Goods or services with different codes are generally presumed dissimilar.

Examiners apply this code-based system mechanically during examination. The similarity of goods is determined by the codes, not by a subjective assessment of commercial overlap, trade channels, or consumer perception.

How Codes Are Assigned

The codes group goods or services that share commonality in terms of:

• Production or provision sector: Goods manufactured by the same type of industry.
• Sales sector: Goods sold through the same distribution channels.
• Raw materials and quality: Goods made from similar materials or having similar characteristics.
• Purpose and method of use: Services offered for similar purposes or in similar ways.

Cross-Class Similarity

The same Similarity Group Code can appear in different Nice Classes. This is one of the most counterintuitive aspects of the system for foreign applicants. For example:

• Jewellery cases (Class 14) and furniture (Class 20) may share the code 20A01, making them similar despite being in different classes.
• Computer programs and video games may share the same code even when they appear in different parts of an international application.

Conversely, goods within the same Nice Class may have different codes and be treated as dissimilar. Within Class 16, for example, stationery (code 25B01) and printed matter (code 26A01) are considered dissimilar because they have different codes.

Why This Matters for Filing Strategy

The code system has direct implications for how you file and protect your mark:

• Class headings are not always acceptable: The JPO does not accept all Nice Class headings as valid goods or services descriptions. You must specify goods at a level that maps to specific Similarity Group Codes.
• A filing in one class may conflict with a mark in another: Because codes cross class boundaries, a prior registration in a seemingly unrelated class may still block your application.
• Too many codes trigger scrutiny: If an application designates goods covering 23 or more Similarity Group Codes in a single class, the JPO may issue a provisional refusal requesting evidence of use or intent to use for each group, or requiring the specification to be narrowed to 22 or fewer.

How to Use the Codes

The JPO publishes the Examination Guidelines for Similar Goods and Services on its website and through the J-PlatPat database. Applicants can search the database to identify:

• The Similarity Group Code for each good or service they intend to designate.
• Other goods or services sharing the same code (and therefore presumed similar).
• Prior registrations covering the same codes, which may conflict with the new application.

This research should be conducted before filing to identify potential conflicts and optimise the goods and services specification.

Madrid System Considerations

International registrations designating Japan through the Madrid Protocol often face problems with the Similarity Group Code system. The goods and services descriptions used in international filings may not map neatly to the JPO’s standard descriptions, resulting in unexpected code assignments or insufficient coverage. For key marks, consider filing a direct national application with goods descriptions specifically tailored to the relevant codes.

Strategic Recommendations

• Research the codes before filing: Identify the Similarity Group Codes for your goods and services and check for conflicting prior marks.
• Use JPO-standard descriptions: Draft your goods and services using the JPO’s standard terminology to ensure correct code assignment.
• Watch for cross-class conflicts: Do not assume that different Nice Classes mean no conflict. Shared codes across classes are common.
• Stay within the 22-code threshold: If your specification covers 23 or more codes, be prepared for a provisional refusal and consider splitting the filing.
• Supplement Madrid designations: International registrations often receive unexpected code assignments. Review the JPO’s code allocation for your IR and consider direct national filings to cover gaps.

Common Mistakes

• Assuming class-wide protection: A registration in Class 9 does not automatically cover all goods in that class. Different Similarity Group Codes within the same class create distinct zones of protection.
• Ignoring cross-class conflicts: Two marks in different Nice Classes may still conflict if their goods share the same Similarity Group Code.
• Using non-standard goods descriptions: The JPO may reject non-standard descriptions or classify them into unexpected codes. This can undermine the entire filing strategy.
• Expecting a case-by-case analysis: During initial examination, the JPO applies the code system mechanically. Arguments about commercial relationship between goods in different codes are unlikely to succeed at the examination stage, though they may carry more weight in opposition or court proceedings.

Defensive Filing Strategy

Understanding the Similarity Group Code system is also essential for defensive filings. If you want to prevent competitors from registering similar marks in related product categories, you need to identify all the relevant Similarity Group Codes and ensure your registrations cover them. This often means filing for specific goods in multiple classes and multiple codes, rather than relying on broad class headings.

For brands with diverse product ranges — such as consumer electronics companies that span hardware, software, accessories, and services — a thorough code mapping exercise before filing can prevent gaps that competitors or squatters could exploit.

Key Takeaway

Japan’s Similarity Group Code system replaces the qualitative, case-by-case assessment of goods similarity used in most other jurisdictions with a mechanical, code-based presumption. The same code in different classes means similar; different codes in the same class means dissimilar. This system is predictable but requires specific local knowledge to navigate. Foreign applicants who file without understanding the codes risk both unexpected conflicts and gaps in protection.