Only locally licensed accountants can own shares in an accounting firm. In principle, Turkish citizenship is required to become a locally licensed accountant, but foreign professionals may be approved in accordance with the principle of reciprocity.
"Article 2 – A) Subject of the profession of accounting and financial advisor:
Enterprises and businesses belonging to real and legal persons;
a) To keep the books, to prepare the balance sheet, profit and loss statements, statements and other documents in accordance with the generally accepted accounting principles and the provisions of the relevant legislation, and to perform similar works.
b) Establishing and developing accounting systems, arranging business, accounting, finance, financial legislation and their applications, or providing consultancy on these issues.
c) To conduct examinations, analyzes, audits, to give written opinions on matters related to financial statements and declarations, to prepare reports and the like, to perform arbitration, expertise and similar works on the subjects written in the above paragraph, based on the documents.
The works listed above; Those who do not be affiliated with a workplace are called independent accountants and financial advisors.
B) Subject of chartered accountant profession:
In addition to carrying out the works written in subparagraphs (b) and (c) of paragraph (a), it is to carry out certification works within the framework of the regulation to be issued in accordance with Article 12 of the Law.
Certified public accountants cannot keep accounting books, open accounting offices and cannot be partners in accounting offices.
[...]
Article 4 – The general conditions of being a member of the profession are as follows:
a) Being a Turkish citizen (the provision about foreign public accountants and financial advisors is reserved).
[...]
Article 8 – The services within the scope of Article 2 from the rights they have obtained in their home country of the persons who are nationals of a foreign state who have officially regulated the profession of public accountant and financial advisor, provided that they have the qualifications sought in the independent accountant financial advisory service under the title of independent accountant financial advisor with the condition of reciprocity. They may be allowed to do so in Turkey with the approval of the President.[...]" (Independent Accountant Financial Advisory and Sworn Financial Advisory Law (No. 3568 of 1989), last amended by Law No. 700 of 2018, Articles 2, 4 and 8 [google translation])
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"Article 30 - Members of more than one profession may engage in professional activities by establishing partnership offices or companies.
In this case;
a) The activities carried out by the members of the profession in these offices or companies are not considered commercial activities.
b) A partnership office or company can only be established between professionals with the same title.
c) They cannot engage in other business other than their field of activity specified in the law.
d) The company or partnership office can only be represented by the partner or partners in the works related to the practice of the profession. [...]" (Regulation on the Procedures and Principles of operations of Independent Accountant, Independent Accountant and Financial Advisor and Sworn-in Certified Accountant (03.01.1990), last amended on 22.05.2015, Article 30 [google translation])
Independent Accountant Financial Advisory and Sworn Financial Advisory Law (No. 3568 of 1989), last amended by Law No. 700 of 2018, Articles 2, 4 and 8 
Regulation on the Procedures and Principles of operations of Independent Accountant, Independent Accountant and Financial Advisor and Sworn-in Certified Accountant (03.01.1990), last amended on 22.05.2015, Article 30
[<a href="https://www.mevzuat.gov.tr/mevzuat?MevzuatNo=3568&MevzuatTur=1&MevzuatTertip=5">Law</a>],[<a href="https://www.mevzuat.gov.tr/mevzuat?MevzuatNo=4650&MevzuatTur=7&MevzuatTertip=5">Reg</a>]