Protection is assembled from the unfair competition chapter of the Commercial Code (Arts. 54–63), the employee’s statutory duties in the Code of Obligations, and Art. 239 of the Criminal Code — each with its own conditions.
Türkiye has no separate trade secrets act. There is no Turkish counterpart to a “Trade Secrets Act”, no domestic statute called an “unfair competition prevention and trade secret protection act”, and no single code chapter you can hand to a foreign board and say: this is the law. The protection nonetheless exists, and in some respects it bites harder than the contractual regimes foreign counsel are used to, because part of it operates whether or not anyone signed anything.
The framework has three legs. The civil regime sits in the unfair competition chapter of the Turkish Commercial Code No. 6102 (TCC), Arts. 54–63. The employment layer sits in the Turkish Code of Obligations No. 6098 (TCO), Arts. 396 and 444–447. The criminal layer sits in Art. 239 of the Turkish Criminal Code No. 5237 (TCK), alongside the offence in Art. 62 TCC. This guide reads each of them against the departing-employee scenario that generates most of these files, and sets out the sequence — warning letter, interim injunction, action — that the statutory text actually supports.
1. Where the Protection Sits, and Why the Absence of an Act Matters
The absence of a dedicated statute has one immediate consequence for pleading. A claim is not framed as “misappropriation of trade secrets”. It is framed as unfair competition under a specific sub-paragraph of Art. 55 TCC, or under the general clause, and usually in parallel as a breach of the employee’s statutory duties. Choosing the wrong statutory hook is the most common structural defect in these files.
The general clause is Art. 54. Its first paragraph states that the purpose of the chapter is to secure honest and undistorted competition in the interest of all participants. Its second paragraph is the operative rule: deceptive conduct and other conduct contrary to the rule of good faith, and commercial practices, affecting relations between competitors or between suppliers and customers, are unfair and unlawful.
Art. 55/1 then lists specific situations — and the opening words of that paragraph are the ones to notice. The listed cases are described as the principal instances of unfair competition. The list is illustrative, not exhaustive. So where the pleaded facts fall outside every sub-paragraph, the general clause in Art. 54/2 remains available: conduct contrary to good faith that affects relations between competitors or between suppliers and customers is unfair and unlawful even if no sub-paragraph describes it. That matters because the sub-paragraph most people reach for first frequently does not fit.
2. Which Parts of Article 55 Actually Protect a Trade Secret?
| Provision | Conduct caught | Who the defendant is | Statutory limit to watch |
|---|---|---|---|
| Art. 55/1-b-3 TCC | Inducing employees, agents or other auxiliary persons to disclose or obtain their employer's or principal's production and business secrets. | The competitor doing the inducing — not the employee. | Requires proof of the inducement, not merely of the departure. |
| Art. 55/1-c TCC | Unauthorised exploitation of another's work product: a tender, calculation or plan entrusted to the defendant; one the defendant ought to have known was entrusted unlawfully; or taking over a market-ready work product by technical reproduction. | Whoever exploits the work product, including a new employer. | Sub-paragraph 3 requires technical reproduction without an appropriate contribution of the defendant's own; independently rewritten output can fall outside it. |
| Art. 55/1-d TCC | Unlawfully disclosing production and business secrets — in particular exploiting or communicating information obtained secretly and without permission, or otherwise learned unlawfully. | Whoever discloses or exploits. | The wording is built around information acquired unlawfully. An employee who learned the information legitimately in the course of duties does not sit squarely inside it. |
That last limit is where cases are lost. Employers instinctively plead Art. 55/1-d against a former employee, and the defence answers that the employee learned everything lawfully, in the ordinary performance of the job, so the sub-paragraph’s own example does not describe them. The Code offers no definition here either: Arts. 54-63 TCC use the phrase “production and business secrets” without defining it. Whether the general professional skill and technical knowledge that an engineer or manager inevitably carries away falls within that concept is assessed on the facts, and its later use does not by itself satisfy Art. 55/1-d unless the unlawful disclosure or unlawful acquisition that the sub-paragraph requires is shown. Against a former employee the stronger pleading is usually Art. 396/4 TCO read together with the general clause in Art. 54/2 TCC, with Art. 55/1-d reserved for the case where the evidence shows extraction — a mass export, a copied repository, a device imaged on the last day.
That evidential distinction is the same one that governs code and product assets, where ownership must be established before misuse can be alleged; the analysis of assignment and ownership defects in our note on source code ownership and IP assignment in Turkish SaaS companies is the natural companion to this section, and the broader statutory picture is set out on our intellectual property page.
3. The Departing Employee: Two Different Duties, Two Different Conditions
The single most useful thing to know about Turkish law here is that secrecy and non-competition are separate duties with separate requirements, and confusing them costs employers cases.
Secrecy — Art. 396/4 TCO, no contract required. The employee may not, during the employment relationship, use for their own benefit or disclose to others information learned in the course of the work, in particular production and business secrets. The sentence that follows is the one that carries the file: to the extent necessary to protect the employer’s legitimate interest, the employee remains bound to keep secrets after the employment relationship has ended. The post-termination duty therefore arises by operation of law. But it is expressly proportionate — bounded by what the employer’s legitimate interest actually requires — so an employer who cannot articulate the specific interest and the specific information is arguing about nothing. Note also Art. 396/3: during employment the employee may not work for a third party for remuneration in breach of the duty of loyalty, and in particular may not compete with their own employer.
Non-competition — Arts. 444–447 TCO, contract required and conditions cumulative. Art. 444 requires the employee to undertake in writing to refrain from competing after the contract ends. A verbal understanding, a handbook, or a clause in an unsigned annexe does not qualify. Art. 444/2 then imposes two cumulative conditions: the employment relationship must have given the employee the opportunity to acquire knowledge of the customer base, production secrets or the employer’s business, and at the same time the use of that knowledge must be of a nature to cause the employer significant harm. Both limbs must hold.
Art. 445 caps the restraint: it may not impose restrictions of place, time and type of work that unfairly endanger the employee’s economic future, and its duration may not exceed two years save in special circumstances. The judge may reduce an excessive restraint in scope or duration. Art. 446 then contains two traps for the employer. Where the breach carries a contractual penalty and the contract says nothing to the contrary, the employee may discharge the obligation by paying the penalty — the employer keeps its claim for loss exceeding that amount, but loses the restraint. And the employer may demand that the offending conduct actually cease only where it expressly reserved that right in writing in the contract. Art. 447 closes the circle: the restraint ends if the employer has no real interest in maintaining it, and it ends if the employer terminated without just cause or the employee terminated for a reason attributable to the employer.
The drafting consequences are concrete, and they belong in the contract rather than in the litigation; they are dealt with in practice on our employment contracts page.
4. The Enforcement Chain: Warning Letter, Injunction, Action
Step one — the notarised warning letter (ihtarname). It fixes the date on which the employer identified the conduct, puts the recipient and the new employer on notice, and converts subsequent conduct into knowing conduct — which matters for the intent element of the criminal provisions and for the Art. 57 TCC route, under which the declaratory, prohibitory and removal claims may also be brought against the person who employs the wrongdoer where the act was committed in the course of their work.
Step two — interim relief. Art. 61 TCC allows the court to order preservation of the existing position, removal of the material situation, prevention of the unfair competition, and correction of false or misleading statements, applying the general rules on interim injunctions — today Art. 389 et seq. of the Code of Civil Procedure No. 6100 (HMK). Art. 389 sets the threshold: a fear that a change in the existing position will make obtaining the right significantly more difficult or wholly impossible, or that delay will cause a disadvantage or serious loss. Art. 390/2 permits the court to decide without hearing the other side where the applicant’s rights must be protected immediately, and Art. 390/3 requires the applicant to prove the merits of the case approximately. Art. 391/1 lets the court order any measure, including that something be done or not be done. Security is the default under Art. 392/1, though the court may dispense with it, giving express reasons, where the application rests on an official document or other conclusive evidence.
Three deadlines then run. An injunction granted without hearing the respondent may be challenged under Art. 394/2, within one week running from the enforcement of the measure where the respondent was present and otherwise from service of the enforcement record. If the injunction was obtained before proceedings, Art. 397/1 requires the main action to be filed within two weeks of the date on which enforcement of the order was requested, failing which the injunction lapses automatically. And Art. 398/1 gives the order teeth: a person who breaches an injunction may, on complaint made within six months of the breach becoming known, be sentenced to up to six months’ disciplinary imprisonment.
Step three — the action itself. Art. 56/1 TCC gives standing to anyone whose customers, credit, professional reputation, commercial activities or other economic interests are damaged or exposed to such a threat — actual loss is not a precondition. The available claims are a declaration that the act is unfair; prohibition of the unfair competition; removal of the resulting material situation, correction of false or misleading statements, and, where unavoidable to prevent the infringement, destruction of the instruments and goods used; damages where there is fault; and non-pecuniary damages where the conditions of Art. 58 TCO are met. The closing sentence of Art. 56/1 is the commercially significant one: as damages under sub-paragraph (d) the judge may also award the value of the benefit the defendant might have obtained as a result of the unfair competition. Art. 56/4 extends the prohibitory and removal judgment to those who acquired the goods from the defendant for commercial purposes.
Forum and mediation follow from the general provisions. Art. 5 TCC gives the commercial court of first instance jurisdiction over all commercial actions regardless of value, and Art. 4/1(c) classifies disputes arising from Arts. 444 and 447 TCO as commercial actions irrespective of whether the parties are merchants — so a non-compete claim against a former employee does not belong before the labour court. Art. 5/A makes recourse to a mediator a precondition to suit only for commercial actions whose subject matter is a sum of money — debt, damages, annulment of objection, negative declaration and restitution. The declaratory, prohibitory and removal claims are therefore not gated, while the damages claim is; where speed matters, the sequencing follows from that split. Related litigation strategy is set out on our unfair competition page.
5. Is Disclosing a Trade Secret a Crime in Türkiye?
Art. 62 TCC makes it an offence to commit one of the Art. 55 acts intentionally, and to deceive employees, agents or other auxiliaries in order to procure their employer’s or principal’s production or trade secrets. It is prosecuted on the complaint of a person entitled to bring the civil action, and is punishable, where the act does not constitute another offence carrying a heavier penalty, by imprisonment of up to two years or a judicial fine. Art. 63 extends Art. 62 to the members or partners of the organ acting for a legal person, and permits security measures specific to legal persons where the act was committed within the framework of that person’s activity.
Art. 239/1 TCK is the sharper instrument. It punishes a person who gives or discloses to unauthorised persons information or documents constituting a commercial, banking or customer secret to which they became privy by reason of their title, duty, profession or art, upon complaint, with imprisonment of one to three years and a judicial fine of up to five thousand days. The second sentence extends the offence to those who obtained the information unlawfully and then pass it on. Art. 239/2 applies the same rule to information relating to scientific discoveries, inventions or industrial application. Art. 239/3 contains a provision that changes the analysis in cross-border cases: where the secret is disclosed to a foreigner not resident in Türkiye, or to that person’s officers, the penalty is increased by one third — and the complaint requirement does not apply.
This is not merely a parallel remedy. Art. 60 TCC limits the Art. 56 actions to one year from the day the claimant learns of the right and three years from the day it arises — but the same article continues that where the unfair competition also constitutes an offence subject to a longer limitation period under the Criminal Code, that longer period applies to the civil actions too. Since both Art. 62 TCC and Art. 239 TCK carry maximum sentences of five years or less, Art. 66/1(e) TCK sets the criminal limitation at eight years. Where the conduct is criminal, the civil claim can therefore survive well past the ordinary one-year and three-year bars. Separately, Art. 73 TCK requires the criminal complaint itself to be filed within six months of the complainant learning of the act and of the identity of the perpetrator.
6. The First Week: Building a File That Survives Cross-Examination
Because no statute defines a trade secret, everything turns on what the holder can show it did to keep the information secret and on what the defendant can be shown to have taken. Two exercises belong at the start.
The evidence-preservation application under Art. 400 HMK allows a party to seek inspection, expert examination or the taking of witness evidence in respect of a fact to be relied on in an action yet to be filed. Art. 400/2 requires a legal interest, and provides that the interest is presumed where the evidence would otherwise be lost or its presentation would become significantly more difficult. Art. 401/1 allows the application to be made either to the court that will hear the main case or to the civil court of peace where the object is located or the witness resides, and Art. 401/2 preserves the notary’s power to record facts under the Notary Law No. 1512. Access logs, export records and mailbox contents are exactly the material this provision exists to capture.
The confidentiality audit is the other half. It converts an assertion into evidence: documented access restrictions, classification markings, need-to-know limits, exit interviews and device returns, and a written confidentiality clause even though Art. 396/4 TCO does not require one — because the clause is what proves the employee knew the information was treated as secret. A downloaded template is not a substitute. Under Art. 444/2 TCO a non-compete is valid only where the two cumulative conditions are met on the facts of that role, and under Art. 446/3 the right to demand that the conduct cease exists only where it was expressly reserved in writing. A restraint drafted without reference to the specific position is exactly the kind Art. 445 empowers the judge to cut down.
The absence of a trade secrets act does not mean the information is unprotected. It means the protection has to be assembled — deliberately, before the employee resigns, and from provisions that each carry their own conditions.
Two neighbouring questions draw on the same materials. Where the person with access is engaged through a third-party provider rather than employed directly, the confidentiality obligation has to survive that structure — and whether the structure itself holds under Article 7 of the Labour Act is the subject of is Employer of Record lawful in Türkiye. Where the secret is embodied in physical items held by someone else and those items are attached for that person’s debts, ownership has to be proved in enforcement rather than in a confidentiality action, as set out in a third-party ownership claim over seized goods.
