Patent Invalidity in Turkey for Foreign Manufacturers: Article 138, Evidence and European Patent Limits
A foreign manufacturer can challenge a Turkish patent through a properly grounded invalidity action; it does not have to accept registration as conclusive proof of validity. Article 138 of Industrial Property Code No. 6769 identifies the grounds, eligible claimants, defendant and time window. Article 139 determines the consequences of invalidity. The application route is essential: a Turkish national patent and a European patent effective in Turkey require the relevant national and treaty rules to be distinguished, particularly when claims are narrowed during litigation.
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This guide is for overseas manufacturers, technology suppliers and investors evaluating a patent that obstructs a Turkish project or is asserted against their supply chain. Its focus is the validity of the right itself. Whether a particular product infringes a valid patent is a separate question, addressed in our guide to patent warnings and non-infringement actions in Turkey. A sound file can analyse both questions without treating them as interchangeable.
Start with the patent’s identity, route and procedural status
Before commissioning a technical invalidity report, obtain the Turkish register entry, complete specification, claims, drawings, priority information and grant history. Record whether the right arose through a national application or the European route. Also identify the registered proprietor and any persons shown in the register as holding rights. The company that sent a warning may not be the same legal person that must be named as the defendant in an invalidity action.
Use the claim version legally relevant to the dispute. An application as first published, a patent as granted and a patent maintained in amended form can contain materially different claims. Prior-art analysis directed at a superseded claim version can miss the question the court must decide. Store the source and retrieval date of each document and distinguish original documents from translations and working annotations.
Article 98(9) expressly provides that grant is not an Office guarantee of the patent’s validity or usefulness. That does not mean registration can be ignored: the challenger must plead and prove the applicable invalidity grounds. A negative commercial opinion about the invention, dissatisfaction with the proprietor’s licence demands or a statement that similar technology is widely used does not replace the statutory analysis.
The five grounds in Article 138 require different evidence
Article 138(1) of Code No. 6769 provides for judicial invalidity after the Office’s final decision on five specified bases. The petition should identify the ground applicable to each challenged claim and explain the evidence supporting it. Combining every ground into a single unparticularised assertion makes it harder to see what is actually disputed and what the expert examination must address.
1. Failure to satisfy patentability requirements
Article 138(1)(a) refers to Articles 82 and 83. Those provisions address patentable subject matter, exclusions and the requirements of novelty, inventive step and industrial applicability. The technical report should identify the relevant requirement rather than simply call the patent unoriginal. A novelty allegation and an inventive-step allegation are not the same argument and should be presented with their respective reasoning.
For documentary prior art, preserve the full document, its publication evidence and the passage relied upon. A modern website showing an older product does not automatically prove what the public could access before the relevant filing or priority date. Where the case relies on an earlier sale, exhibition, use or technical disclosure, connect the asserted event to reliable dates and to the actual technical features disclosed.
2. Insufficient disclosure
Article 138(1)(b) refers to Article 92(1), (2) and (3). The issue is whether the invention is disclosed with the legally required sufficiency, not whether a marketing brochure is easy for a non-specialist to understand. Identify what the specification teaches, what is allegedly missing and why that deficiency matters to carrying out the invention. Technical expertise must be matched to the field of the patent.
Do not confuse a broad commercial ambition with an enabled technical teaching. The analysis should distinguish the claimed subject matter, the disclosed examples and the skilled person’s relevant knowledge. Where experiments are relied upon, preserve the protocol, materials, conditions and complete results, including results that do not support the proposed challenge. Selective laboratory records can create an inaccurate picture of the alleged deficiency.
3. Subject matter extending beyond the original application
Article 138(1)(c) addresses subject matter exceeding the application as initially filed. It also identifies the corresponding original-application comparison for divisional applications under Article 91 and applications arising under Article 110(3)(b). This ground requires a document-to-document comparison. A current claim may be commercially valuable yet still raise a question about whether its technical content was present in the relevant original disclosure.
Prepare an amendment history with the original text, each relevant amendment and the proprietor’s explanation of its basis. Do not use a later family member’s disclosure as though it were automatically part of the original Turkish application. The analysis must explain the correct reference document and the particular technical teaching alleged to have been added.
4. Lack of entitlement to the patent
Article 138(1)(ç) concerns proof that the proprietor was not entitled to seek the patent under Article 109. This ground has a special standing restriction: under Article 138(3) and (6), only the inventor or the inventor’s successors can invoke it. A commercial competitor cannot rely on a general interest in market access to sidestep that express restriction.
For a corporate claimant asserting succession, investigate the chain from the inventor through employment, assignment or another alleged transfer. Ownership evidence is different from technical prior art. A manufacturing invoice does not itself establish inventorship, and a patent-family database naming an inventor does not resolve every issue of entitlement or succession.
5. Extension of the protection conferred
Article 138(1)(d) addresses an extension of the patent’s protection. Distinguish this from adding subject matter to the original disclosure. The challenge should identify the protection before and after the disputed change and explain the asserted expansion. Keeping these grounds separate helps the court and technical experts assess the legally relevant comparison rather than treating all amendments as the same defect.
Who can sue, who must be sued and how long is available?
Article 138(6) permits interested persons, public prosecutors and relevant public institutions or organisations to seek invalidity, subject to the special entitlement restriction. An overseas company should explain the interest connecting it to the challenged Turkish right. A threatened distribution project, an asserted supply-chain infringement or a dispute concerning licensed technology can provide factual context, but the legal interest must be established in the actual case.
Under Article 138(5), the action is brought against the person recorded as proprietor. Other persons shown in the register as holding rights over the patent must also be notified so that they can participate. Obtain a fresh register record before filing and monitor changes during the case. A corporate name change and a transfer to a different legal person should not be treated as the same event.
The statutory window lasts throughout the patent’s protection and for five years following termination of the right. This is not a five-year period beginning with grant. It also means expiry or another termination event does not automatically make every invalidity dispute pointless. The remaining legal interest and the consequences sought must still be examined rather than assuming the case is either always available or always unnecessary after termination.
Do not confuse the opposition deadline with the invalidity-action window
Article 99 provides a national post-grant opposition procedure. Third parties have six months from publication of the grant decision in the Bulletin to oppose on the specified patentability, sufficiency or added-subject-matter grounds, with the required fee and procedural conditions. Article 99(2) attaches consequences to failure to pay the fee within that period or to comply with the prescribed opposition requirements.
Article 138 governs the judicial invalidity action. Missing the Article 99 opposition period is not the same as expiry of the Article 138(5) litigation window. Conversely, preparing a court case should not lead a business to neglect a still-open opposition deadline that may be relevant to its strategy. Keep the two procedures, their decision-makers, grounds and dates separately diarised.
Article 138(2) prevents the court from deciding invalidity requests under Article 138(1)(a), (b) and (c) before the publications specified in Article 99(3) or (7). The relevant final-decision publication therefore matters. A docket entry showing only that the patent was initially granted does not establish that every statutory procedural stage has been completed.
European opposition is a different procedure. Article 99 of the European Patent Convention provides a nine-month period from publication of the mention of grant of the European patent in the European Patent Bulletin. Do not substitute that period for the six-month period in Turkish Code Article 99, or vice versa. The identical article number does not make the two legal regimes identical.
Partial invalidity: national patents and European patents must be separated
For the national statutory rule, Article 138(4) provides for cancellation of the claim or claims affected by invalidity while preserving claims that satisfy Articles 82 and 83. It states that part of a single claim cannot be declared invalid under that rule. If an independent claim is invalidated, dependent claims require separate assessment against the patentability requirements; they are not preserved merely because they are labelled dependent.
A report seeking invalidity of an entire patent should therefore explain the position of every claim included in the requested relief. Showing a problem with one independent claim does not justify ignoring other claim combinations. The petition, claim chart and proposed expert questions should align so that the requested judgment matches the technical case actually developed.
European patents require the treaty rule to be addressed. EPC Article 138(2) and (3) expressly provide for limitation by amendment of claims and the proprietor’s right to limit a European patent in validity proceedings before the competent court or authority. It would therefore be misleading to announce a universal ban on claim limitation in all Turkish patent litigation by quoting only the national Code’s wording.
For a European patent effective in Turkey, identify the amendment requested, its legal basis, the operative claim text and its impact on the invalidity grounds. Coordinate the Turkish proceedings with the relevant European prosecution or opposition record without assuming that an argument made in one forum automatically resolves all procedural questions in the other. The actual court file and treaty framework must be considered together.
What a successful invalidity decision does—and does not undo
Article 139(1) gives invalidity retrospective effect: the statutory protection is treated as never having arisen. However, Article 139(2) identifies important exceptions. Subject to the preserved damages claims of persons harmed by the proprietor’s gross negligence or bad faith, the retrospective effect does not disturb infringement judgments that were both legally final and executed before invalidity, or contracts concluded and performed before invalidity.
The cumulative wording matters. Do not shorten the first exception to every previous judgment or the second to every signed agreement. Review finality, execution, contract performance and the relevant dates. A group-level assertion that all historic payments must immediately be refunded is not a substitute for assessing the statutory exceptions and the particular payment history.
Article 139(3) permits a claim for partial or complete repayment of amounts paid under the contracts described in Article 139(2)(b), where equity justifies it. This is a basis to request repayment, not an automatic rule returning every royalty. The agreement may also involve know-how, technical assistance or other rights, so identify what each payment bought. Our international IP licence guide addresses the separate question of the law governing contractual obligations.
Under Article 139(4), a final invalidity judgment has effect against everyone; the court informs the Office, and the invalidated patent is removed from the register with publication in the Bulletin. Article 162 states that decisions in actions seeking annulment of Board decisions or invalidity cannot be executed before finality, including their ancillary parts. Do not describe an unfinalised first-instance outcome as a completed register cancellation.
A practical evidence file for an overseas claimant
Organise the file around issues rather than a large undifferentiated data room. Keep one register-and-procedure section, one claim-version section, one evidence section for each invalidity ground and one chronology of warnings, sales, opposition steps and court papers. This structure makes it easier to identify missing proof before expert work becomes expensive or a procedural deadline is missed.
Technical documents should retain their original language and source alongside any translation. Mark translations as translations, preserve complete documents and make clear which passages support which propositions. For laboratory material or product samples, record the model, batch or version, the person providing the item and the conditions of examination. The objective is a traceable technical record, not simply a persuasive-looking presentation.
Separate the people needed for litigation, registered Office representation and technical analysis. A Turkish lawyer is not automatically a registered patent attorney, and a patent attorney’s technical opinion is not a court judgment. Article 160 regulates representation before TÜRKPATENT, including representation requirements for persons domiciled abroad. Allocate each task to the appropriate professional capacity and preserve communication between the legal and technical teams.
Finally, consider interim exposure separately. Filing an invalidity action is not itself a licence, a suspension of the patent or a court order permitting commercial exploitation. Article 159 governs interim measures under its conditions. Business decisions about shipments, ongoing manufacture and customer commitments should reflect the orders actually made, not an assumption that the challenge has already succeeded. The Turkish-language invalidity petition guide provides a related procedural document framework, not a replacement for claim-specific technical work.
Frequently asked questions
Can a foreign company challenge a Turkish patent?
Article 138 allows interested persons to seek invalidity. The company must establish the relevant interest and statutory grounds, while entitlement-based invalidity is reserved to the inventor or successors.
Is the deadline five years after grant?
No. Article 138(5) allows the action during the protection period and for five years following termination of the right. The six-month national post-grant opposition period is a different rule.
Does missing national opposition prevent every later invalidity action?
No. Article 99 opposition and Article 138 judicial invalidity are distinct procedures. The litigation window, standing, grounds and procedural stage must be assessed separately.
Can a competitor allege that someone else invented the technology?
The lack-of-entitlement ground in Article 138 is reserved to the inventor or successors. A competitor’s commercial interest does not itself confer standing to rely on that ground.
Must the challenge cover every claim?
The requested relief must match the grounds and evidence. Article 138(4) permits partial invalidity and requires assessment of claims that remain, including the position of dependent claims.
Can European patent claims be limited during validity proceedings?
EPC Article 138(3) gives the proprietor that right. The European patent’s treaty framework must be distinguished from the national Code’s partial-invalidity wording.
Are all royalties automatically refunded after invalidity?
No. Article 139 protects specified concluded and performed contracts from automatic retrospective disruption, while allowing an equitable claim for partial or complete repayment under paragraph 3.
Does a first-instance invalidity decision immediately cancel the register entry?
Finality matters. Article 139(4) governs the consequences of the final judgment and notification to the Office; Article 162 prevents execution of the specified judgments before finality.
Does filing invalidity proceedings permit importation?
Filing does not itself confer a licence or suspend the patent. Interim measures and existing orders must be examined separately under Article 159 and applicable procedural rules.
Who is the defendant in the national invalidity action?
Article 138(5) identifies the registered proprietor. Other persons recorded as holding rights over the patent must be notified so that they can participate.
Legal sources
Primary provisions: Code No. 6769, Articles 82–83, 92, 98–99, 138–139, 159–160 and 162; EPC Article 99; and EPC Article 138. The TÜRKPATENT legislation directory provides the official national legislation links. This article is an English explanation, not an official translation or an assessment of any identified patent.
Discuss a Turkish patent validity dispute
For an initial enquiry, provide the patent number, your company’s role, relevant deadlines and whether proceedings already exist. Do not send trade secrets, confidential research or sensitive identity documents through the initial form.
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