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CategoryIP Litigation
Published28 August 2026
Authors
Uğurcan TekinPartner
İnci ÖzçilsalAttorney at Law

Trademark Invalidity Actions in Türkiye: Grounds, Acquiescence and the Difference from Administrative Revocation

Trademark registration creates a strong presumption, but not an absolute one. A legal defect present at the moment of registration allows the mark to be invalidated later. The Industrial Property Code No. 6769 governs this regime expressly: where one of the absolute grounds of Article 5 or the relative grounds of Article 6 exists, the court declares the mark invalid (Article 25). An invalidity judgment is, as a rule, retroactive; the mark is treated as if it had never come into existence (Article 27). That severe consequence makes the invalidity action the sharpest instrument in industrial property litigation.

The parties to the action are also defined by statute. Invalidity may be sought by persons with a legal interest, and public prosecutors and the relevant public institutions also have standing (Article 25). The action is directed against the person recorded in the registry as proprietor. The competent court is the specialised civil court for intellectual and industrial property rights (Article 156); where none exists, the designated civil courts of first instance hear the case.

An invalidity judgment is, as a rule, retroactive: a defect at the moment of registration can mean the mark is treated as never having existed.

The Grounds of Invalidity

The grounds fall into two groups. The first comprises the absolute grounds: lack of distinctiveness, descriptiveness and the registration of signs in common sectoral use are the principal examples, and these grounds protect the public interest. The second comprises the relative grounds: likelihood of confusion with an earlier mark, genuine ownership based on earlier use, earlier rights such as trade names, and bad faith. These protect earlier right holders. A relative ground not raised at the opposition stage may still be raised in an invalidity action; missing the opposition window does not extinguish the right altogether.

Partial invalidity is also possible. Where the defect concerns only some of the goods or services covered, invalidity is declared only for those goods or services, and the mark survives for the remainder. Litigation strategy must therefore be built on a fine-grained analysis of the specification.

Loss of Rights Through Acquiescence

The statute does not grant the earlier right holder an unlimited right to wait. An earlier right holder who knew, or should have known, of the use of the later mark and remained silent for five consecutive years can no longer invoke its own mark as a ground of invalidity (Article 25). The single exception is bad faith: where the later mark was registered in bad faith, the acquiescence period does not run. In practice the rule cuts both ways. Right holders must monitor the market and act within a reasonable time against infringing uses; conversely, for marks that have long coexisted, the invalidity threat weakens with the passage of time.

“In invalidity litigation, time works in both directions: the earlier right holder who waits can lose the right to act, while the later mark that is left alone grows stronger with every passing year.”

The Difference from Administrative Revocation

Invalidity and administrative revocation are often confused, yet the two institutions answer different problems. Invalidity rests on a defect existing at the moment of registration and is sought from the court. Revocation rests on circumstances arising after registration and is pursued before TÜRKPATENT (Article 26): non-use, the mark becoming a common name, and the mark becoming misleading are grounds of revocation. The effects differ as well. Invalidity operates, as a rule, retroactively; revocation, as a rule, takes effect from the date of the request onwards (Article 27). Choosing the correct route depends on the nature of the defect: a registration flawed from the outset points to invalidity, while a mark that lost its function later points to revocation.

The two routes can also be weighed together. In practice there are cases where both non-use revocation and invalidity grounds exist against the same mark at the same time, and there the comparison must be made on cost, duration and burden of proof. The workings of the administrative revocation route are examined in detail in a separate article of ours.

Proof and Strategy

The burden of proof in an invalidity action lies, as a rule, on the claimant. In confusion-based actions, the analysis of sign and goods similarity is decisive. In actions based on genuine ownership, the earlier use must be established with dated documents: invoices, catalogues, advertising records and commercial correspondence are the core instruments. In bad-faith actions, documenting the parties' past relationship carries the weight. A sober assessment of the evidentiary position before filing is essential, because an invalidity action brought on weak evidence can produce the unwanted result of strengthening the opponent's mark with a court judgment.

A Pre-Action Checklist

  • Identify the nature of the defect: a defect at registration points to invalidity, a later development points to revocation.
  • Calculate the acquiescence risk: establish, with documents, when the later mark's use became known and how much time has passed.
  • Assess partial invalidity: frame the claim by reference to the specification of goods and services.
  • Collect the evidence of the earlier right before filing, building a chain of dated documents.
  • Compare the administrative revocation alternative on cost and duration.
  • Anticipate counterclaims: analyse the defendant's possible non-use defence and cross-claims for invalidity from the outset.

The invalidity action is a mechanism that corrects the registry: it removes from the market a mark that should never have been registered. Used carelessly, however, the same mechanism can turn against the claimant. Choosing the right grounds, observing the time limits and completing the evidence file before filing are the preconditions of success. And because the judgment operates retroactively, the invalidity risk should also be priced into commercial agreements, with retrospective due diligence in every trademark acquisition.

Sources

  • Industrial Property Code No. 6769, Articles 5, 6, 25, 26, 27 and 156
  • mevzuat.gov.tr: current text of the cited statute
Related practice areaDispute Resolution & Litigation→

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