The consequence of choosing the wrong class is captured in one sentence: protection does not arise where you expected it. You hold a certificate, but that certificate gives you no rights in the field where you actually use the mark.
The mistake is usually discovered late — when a competitor starts using the same name, or when a marketplace rejects your brand registration. By then the options for correction are limited.
There are three distinct types of error, each with a different consequence:
| Error | Consequence | Correctable? |
|---|---|---|
| Missing class — not claiming a field you need | No protection there | Only by a new application, with a new date |
| Excess class — claiming a field you do not use | Cost + revocation risk after 5 years | Yes, the scope can be narrowed |
| Mistaken class — claiming the wrong field | No protection and wasted cost | A new application for the right class |
Missing Class: The Most Expensive Mistake
The commonest example is a business selling its own branded goods that takes only class 35 (retail). Class 35 protects the retail service, not use of the mark on the product.
The result:
- Someone else may register the same name in the goods class.
- That person may use the name on their product and assert it against you.
- Because marketplace brand protection programmes may look for a registration in the goods class, your brand registration may be refused.
The most frustrating aspect of a missing class is that correction has no retrospective effect. You file a new application, but its date is today; if someone took the same name in that class in the meantime, you are too late.
Excess Class: The Silent Cost
Unnecessary classes create no immediate problem. The problem starts in year five.
A mark not put to genuine use for the goods and services registered within five years of registration may be subject to a revocation request (Article 26). Revocation can be partial — confined to the unused classes.
This typically arises when a competitor wants to file something that clashes with you: they can have your unused class revoked and clear the obstacle in front of them.
Add to that the cost repeated at every renewal, and the risk of clashing with marks in those classes. To find the right number see How Many Classes Should a Trademark Cover?
Mistaken Class: Both at Once
Writing the activity into an entirely different class means both a protection gap and a wasted budget. Common confusions:
- Manufacture versus sale. Making the product belongs to the relevant goods class; selling it belongs to class 35.
- Software product versus software service. Downloadable software is class 9; SaaS and development services are class 42: Which class does software fall into?
- Restaurant versus food product. Providing food and drink is class 43; packaged food is class 29 or 30.
- Education service versus educational material. Courses are class 41; printed material is class 16.
- Copying activity codes. Commercial registry activity codes and Nice classes are different systems and do not correspond.
Sub-Group Error: Right Class, Wrong Scope
Selecting the right class number is not enough. What you actually select in the TÜRKPATENT list is sub-groups, and scope is determined at that level.
The best-known example is class 35: retail and store services form their own sub-group and do not fall within scope unless expressly claimed. Many businesses that say "I have class 35" in fact hold a registration covering only advertising and business management services.
Note also that under Communiqué 2026/2, when retail and wholesale services are described in class 35, only goods groups may be listed. See Class 35: Retail and Store Services.
Routes of Correction
Narrowing the scope — possible
A proprietor may limit the goods or services covered by the registration. This is used to shed unnecessary classes or to render an opposition moot.
Widening the scope — not possible
The scope cannot be widened, either during the application or after registration. The only route for a missing field is a new application.
A new application
A separate application is filed for the missing classes. It is an independent file with its own fee, its own process and its own date. Before filing, check whether there is a clash in those classes: search the existing register.
Corrections arising from the communiqué
When the classification communiqué changes, TÜRKPATENT may make the adjustments needed for conformity. Following Communiqué 2026/2, adjustments for applications filed after 1 January 2026 are made of the Office's own motion and free of charge. Earlier applications are not updated automatically.
This does not remove your responsibility for choosing the class that matches your activity — the Office ensures conformity with the list, not with your business model.
A Checklist for Your Existing Registration
If you hold a registration, ask these five questions:
- Does the list of goods and services on the certificate match what you actually do today?
- If you sell goods, is the goods class within scope?
- If you took class 35, is the retail sub-group expressly stated?
- If five years have passed since registration, can you show use in every class?
- Has your business model changed in the last five years — from a physical shop to e-commerce, for instance?
A "no" to any of these means there is a gap between your scope and your actual activity.
Let Us Review Your Scope
Share your certificate and what you do today, and our trademark registration team will identify the gap between the scope and your real use, and assess whether a supplementary application is needed.
To set the method up correctly from the start: How to Choose Trademark Classes.