Contract Law
This section covers the core institutions of the law of obligations — from contract formation to termination, from performance to adaptation. The articles are prepared in light of the Turkish Code of Obligations (No. 6098).
Invalidity of Contract: Absolute Nullity (Butlan) and Voidability
TBK m.27, m.28 and defects of intent
When is a contract invalid? Absolute nullity, voidability, defects of intent, unjust exploitation and lack of form under the Turkish Code of Obligations.
For a contract to be validly formed, the parties must have capacity, the declarations of intent must be sound, the subject matter must be possible and not contrary to law or morality, and the required form (if any) must be observed. Lack of any of these results, depending on the type of contract, either in absolute nullity or in voidability.
Absolute Nullity (Butlan) — TBK m.27
Under TBK m.27/1, contracts contrary to mandatory rules, morals, public order or personality rights, or whose subject matter is impossible, are absolutely null. Nullity operates from inception (ex tunc), does not depend on a party's request and is considered by the court of its own motion.
Partial nullity is possible: under TBK m.27/2, nullity of some clauses does not affect the validity of the others; however, if it appears clearly that the contract would not have been concluded without the void clause, the whole contract is null.
Voidability — Defects of Intent
For qualifying mistake, fraud or duress, TBK m.30,36 and 37 provide that the affected party is not bound; exercise of that protection and confirmation are governed by m.39. Competing doctrinal explanations should not be reduced to an absolute statement that every such contract is fully valid from inception.
The right to set aside based on defect of intent must be exercised within one year of learning of the defect or of the cessation of the effect of duress (TBK m.39). The period is one of forfeiture; lapse confirms the contract and it remains in force.
Unjust Exploitation (Gabin) — TBK m.28
If a contract shows a clear disproportion in performances, brought about by exploiting the disadvantaged party's distress, thoughtlessness or inexperience, the injured party may, depending on the circumstances, either declare that it does not consider itself bound and demand restitution of what it gave, or remain bound and demand correction of the disproportion.
This right must be exercised within one year of learning of the thoughtlessness or inexperience (or of the cessation of the distress), and in any event within five years of contract formation.
Lack of Form and Its Consequences
Contracts concluded without the prescribed statutory form are, as a rule, absolutely null (TBK m.12/2). Promises to sell immovables (TBK m.29), construction contracts in return for share, suretyship (TBK m.583) and donations (TBK m.288) require validity forms.
Where performance has substantially been carried out, the Court of Cassation may refuse to entertain later reliance on lack of form as contrary to good faith; this exception is, however, narrowly construed.
Practical Considerations
In contractual disputes, not only the signed text but also offer correspondence, revision history, invoices, delivery records, payment records, formal notices and the parties' subsequent conduct are taken into account. The formation, performance and termination of a contract often acquire meaning only through these ancillary documents.
Form requirements, authority of representation, penalty clauses, exclusion-of-liability provisions, standard terms and consumer-protection rules may all affect the validity or enforceability of a contract. For standard terms, the requirements of clear information, an opportunity to learn their content and acceptance under Article 21 of the Code of Obligations must be considered, together with any special consumer rules.
Before any dispute arises, the scope of obligations, delivery date, defect notice, default notice, interest and competent-court clauses should be drafted explicitly. Vague provisions may give rise to interpretation disputes and to difficulties of proof later on.
Statutory Provisions
The Turkish version of this page provides the relevant statutory texts or selected excerpts in Turkish. For the current consolidated legislation, our primary reference is mevzuat.gov.tr ; the Official Gazette and relevant court decisions should also be consulted for amendments, commencement and annulment provisions.
Conclusion
The distinction between absolute nullity and voidability determines the available claims and the applicable periods. Letting the one-year voidability period lapse may irreversibly cure a legally defective contract.
This article is for information purposes only and does not constitute legal advice. If you would like professional assistance on a specific matter, you may request a consultation.
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