Foreign law firms are solely entitled to provide legal consulting services on foreign/ international law. Foreign lawyers (and dual citizens) are allowed to practice in local law firms (e.g. civil & criminal cases) on the basis of reciprocity provided under treaties to which Azerbaijan is a party, but not allowed to hold equity in law firms. For the purposes of the OECD FDI Regualtory Restrictiveness Index, the reciprocity is not considered becasue it is conceded only under the existence of a treaty. 
"Article 26. Provision of legal assistance by foreigners
I. According to the requirements of this law, the provision of legal assistance by foreign lawyers in the territory of the Republic of Azerbaijan is limited only to advice and opinions on the application of the laws of the state to which the foreigner belongs or international legal norms.
II. In the territory of the Republic of Azerbaijan, foreign lawyers are admitted to judicial proceedings in civil cases, criminal cases, cases related to administrative and commercial disputes, and cases related to administrative errors based on mutual relations in accordance with the international agreements to which the Republic of Azerbaijan is a party." (Law of the Republic of Azerbaijan "About lawyers and advocacy activities", dated December 28, 1999 № 783-IQ, last amended by Law of the Republic of Azerbaijan No. 150-VIQD dated June 29, 2020 [google translated])
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"Article 4. Advocacy [8]
I. A person who has been admitted to the membership of the Bar in the prescribed manner and who has taken the oath of a lawyer may carry out his lawyer activity.
[…]
Article 5. General rules of representation […]
V. Advocacy can be performed individually or in the structure of advocates (lawyers, bureaus, lawyer firms, etc.) established by a lawyer (lawyers) in accordance with the legislation of the Republic of Azerbaijan. Organizational-legal form of advocacy is selected by advocates on a voluntary basis. [13]
VI. The implementation of the advocacy activity begins after the state registration of the organization in the legal form chosen for this activity. The founders of this body should be solely lawyers.
[...]
Article 8. Attorney
II. Dual citizenship, commitment to other states, legally incompetent, or limited capacity, inability to act as a lawyer for mental disorders, legally severe, severe, or especially in the manner prescribed by law. Persons with or without conviction for committing a felony, who have come into force on the application of compulsory medical measures, may not be lawyers.
[...]
Article 8-1. Assistant of Attorney [22]
I. A citizen of the Republic of Azerbaijan with higher legal education may be an assistant to a lawyer.
[...]
Article 26. Legal assistance by aliens
I. According to the requirements of this law, the provision of legal assistance by foreign lawyers in the territory of the Republic of Azerbaijan is limited to advice and opinions on the application of the law of the foreign country or the norms of international law.
II. Foreign lawyers in the territory of the Republic of Azerbaijan shall be allowed to execute proceedings on civil cases, criminal cases, administrative and economic disputes, and administrative offenses on the basis of reciprocity in accordance with international treaties to which the Republic of Azerbaijan is a party. [...]" (Law of the Republic of Azerbaijan "About lawyers and advocacy activities", dated December 28, 1999 № 783-IQ [google translated])
Law of the Republic of Azerbaijan "About lawyers and advocacy activities", dated December 28, 1999 № 783-IQ [google translated]
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