In fact, according to the Turkish Code of Obligations, the contract is established with the mutual and appropriate will statement of the parties. The will statement can be either explicit or implicit. The validity of contracts does not depend on any form unless there is a contrary provision in the law. Accordingly, contracts can be written or verbal. The contractual relationship established orally is not recommended in our opinion as there may be a proof problem in future conflicts.
In practice, it is seen that especially international contracts are prepared in a foreign language. This does not affect the validity of the contract. Nevertheless, in Turkish law, the provisions of the "Law on the Compulsory Use of Turkish in Economic Enterprises No. 805" regarding the contracts prepared in a foreign language should be observed. According to article 1 of this regulation “In Turkey, all types of Turkish companies and Turkish institutions are obliged to keep their transactions, contracts, correspondence and account books in Turkish”. Accordingly, Turkish companies and institutions are required to keep all kinds of transactions, contracts, correspondence, accounts, and books located in Turkish territory in Turkish.
From the first article of the Law No. 805, it arises from the negative interpretation of the provision that Turkish companies and establishments do not have to use Turkish in their business and transactions abroad.
It is pointed out in article 2 of the Law No. 805 that foreign companies and institutions should use Turkish in their correspondence, transactions and contacts with Turkish companies and the Turkish State. It is not clearly understood from the text of the law whether this contract should be prepared in Turkish or not if foreign companies and establishments make contracts with Turkish companies and the Turkish State. Although there is no consensus on the subject in the doctrine, the majority thinks that in such a case, the preparation of contracts in a foreign language is not against the law.
The Supreme Court stated that , contrary to the dominant view in the doctrine, the contract among the foreign companies or institutions and Turkish companies or Turkish State should be signed in Turkish (Y.11.HD. 04.03.2013 T. 2012/4088 E. 2013/3972 K .).
In another decision (Y.11.HD. 2009/2051 E. 2009/5292 K.) of the Supreme Court regarding the subject “According to the 4th article of the Law No. 805, if the companies and establishments mentioned in the 1st article do not carry out their transactions in Turkish, they cannot use these documents on the trial ”. However, not the validity of the contracts, but the availability of proof is mentioned here.
The sanction for violation of the Law No. 805 is regulated in article 7. According to the related article, "The person who acts against the provisions of this Law is punished with a judicial fine not less than a hundred days". As can be seen, the enforcement of the law is a judicial fine, that is, economic.
As a result, contracts signed against this law may create serious problems for the parties. Many companies doing business in Turkey, unfortunately, are not aware of this situation. To avoid loss of rights due to the law numbered 805, it would be quite logical to sign the contracts in both Turkish and foreign languages and to give preference to the copy prepared in Turkish in case of conflict.