Enterprises providing legal consultancy services (law firms) and partnerships can only be created by groups of lawyers authorised to practice in Bulgaria, the EU/EEA or Switzerland. Only Bulgarian and EU/EEA/Swiss citizens are entitled of becoming a lawyer upon meeting the conditions established in the legislation. In addition, law firms must be locally incorporated and registered in the Bar Council.
"Section II. Law Firm
Art. 57. (1) (Amended - SG No. 53 of 2010, amended - SG No. 97 of 2012, amended - SG No. 17 of 2021) A law firm may formed by one or more lawyers, as well as lawyers from the European Union, permanently established on the territory of the Republic of Bulgaria or temporarily practicing the profession under the conditions of art. 19 years The law firm is a legal entity.
(2) Persons who are not lawyers may not be members of the law society.
(3) (Supplement - SG No. 97 of 2012) A lawyer, as well as a lawyer from the European Union, cannot be a partner in more than one law firm.
(4) The law firm and its partners may not represent clients who have conflicting interests.
Art. 58. (1) (Amended - SG No. 53 of 2010, amended - SG No. 97 of 2012, previous text of Art. 58 - SG No. 17 of 2021) The lawyer a company is established by a contract between two or more lawyers or lawyers from the European Union, in writing, which contains:
1. name of the company;
2. (supplemented - SG No. 97 of 2012) the names and addresses of the offices of the lawyers - partners. When the founder or partner is a lawyer from the European Union who temporarily practices the legal profession on the territory of the Republic of Bulgaria under the conditions of Art. 19d , the contract contains in addition to the name of the lawyer and his address in the country where he is permanently established;
3. the seat and address of the company;
4. subject of activity;
5. the type and amount of the contributions of each partner and the assessment of non-monetary contributions;
6. the method of distribution of income and expenses;
7. the way of management and representation of the company;
8. the conditions for accepting new partners;
9. the conditions for leaving partners;
10. the grounds for excluding a partner;
11. the grounds for termination of the company;
12. the method of liquidation of the company.
(2) (New - SG No. 17 of 2021) When the law firm is established by one lawyer, instead of a contract, a written act of incorporation with the relevant content under para. 1." (Attorney Act, SG. 55/25 Jun 2004, last amended 17 February 2021)
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"Chapter one. - GENERAL PROVISIONS […]
Article 3.
(1) (suppl. –SG 97/12) The profession of lawyer may only be pursued by an attorney or a European Union lawyer practicing independently or in partnership under this Act.
(2) An attorney can be only an individual who has taken oath and is registered in the register of the Bar Association.
Chapter two.
ACQUISITION OF RIGHTS OF ATTORNEY
Article 4.
(1) (suppl. –SG 97/12) Any legally capable Bulgarian citizen or a citizen of the European Union, of a state –party to the Agreement on the European Economic Area or of the Swiss Confederation may become an attorney, if he/she meets the following conditions:
[...]
Chapter three. - "A" EUROPEAN UNION LAWYERS (NEW –SG 97/12)
Section I. General provisions (new –SG 97/12)
Article 11. (in force from 01.01.2007; amend. and suppl. - SG 10/06; amend. –SG 53/10; amend. – SG 97/12)
(1) A European Union lawyer shall be any citizen of the European Union, of a state –party to the Agreement on the European Economic Area or of the Swiss Confederation, who has acquired authorization to pursue the legal profession according the legislation of any of the aforementioned states. [...]
(4) European Union lawyers may practise the legal profession in the Republic of Bulgaria as a member of a group, unless the group includes non-lawyers. [...]
(9) Upon application by a European Union lawyer in the Unified register of foreign attorneys at the Supreme Bar Council and in the register of foreign attorneys of the respective bar association shall be entered, the name (company name) of the group in which he or she is a member in the Member State by origin.
[...]
Chapter ten. - JOINT EXERCISING OF THE ATTORNEY PROFESSION
Section I. Lawfirm
Art. 52. (1) (suppl. –SG 53/10; amend. –SG 97/12) Attorneys, law firms, European Union lawyers and groups of lawyers, who are permanently established in the territory of the republic of Bulgaria or who practise the profession of lawyer, can bring together their activities by contract for partnership. [...]
(2) (suppl. –SG 97/12) By a partnership contract can be associated attorneys or European Union lawyers and law firms, entered in the registers of different bar associations. [...]
Art. 54. (1) (suppl. –SG 97/12) Partnered attorneys under Art. 52, para 1 shall practice the profession of lawyer in a way supposing the existence of shared clients, which shall be considered publicly announced with the registration of art. 53.
(2) (amend. –SG 97/12) In his papers each of the partnered attorneys, European Union lawyers and law firms may indicate the association with the words "in partnership" or "in association with", listing the other partnered persons or part of them.
[...]
Section II. Lawfirm
Art. 57. (1) (suppl. –SG 53/10) Attorneys and foreign attorneys entered in the Unified register of foreign attorneys can form law firm. The law firm shall be a corporate body.
(2) In the law firm, cannot be members persons who are not attorneys.
(3) An attorney cannot be member of more than one law firm.
[...]
Art. 58. (suppl. –SG 53/10; suppl. –SG 97/12) Law firms shall be founded with contracts in writing between two or more attorneys and/or European Union lawyers and shall contain the following: 
[...]
Art. 58a. (New - SG 97/12) (1) A grouping of European Union lawyers who have permanently established themselves in the Republic of Bulgaria according to Art. 16, para 1 may be established as a law firm in the territory of the republic of Bulgaria.
(2) Members of a law firm, individually or jointly, may be attorneys and European Union lawyers permanently established in the Republic of Bulgaria.
(3) The registration and activities of law firms shall be carried out pursuant to Art. 57, 58 and 60-75, provided the application and the contract referred to in Art. 58 are to be submitted along with:
1. a document issued by a body of the bar at the seat of the grouping in the Member State of origin which confirms the existence of the grouping and its name, seat, registered office and form of association;
2. a document issued by the grouping which authorises specific attorneys or European Union lawyers to establish a law firm in the Republic of Bulgaria.
[...]
Section III - Contracts between attorneys and law firms
Art. 76. (amend. –SG 53/10; amend. –SG 97/12) Attorneys, law firms, European Union lawyers and groupings of European Union lawyers, permanently established or pursuing the profession of lawyer on a temporary basis pursuant to Art. 19d in the territory of the Republic of Bulgaria, may enter into cooperation contracts with one another. The contract shall regulate the performance of certain legal work, or work on certain cases shall be taken jointly.
Art. 77. (1) (amend. –SG 53/10; amend. –SG 97/12) Attorneys, law firms, European Union lawyers and groupings of European Union lawyers, permanently established or pursuing the profession of lawyer on a temporary basis pursuant to Art. 19d in the territory of the Republic of Bulgaria, may enter into written contracts with one another, for a fixed or for an indefinite period, permanent work in return for a fixed remuneration. Unless otherwise provided for in the contract, the remuneration shall be payable on a monthly basis. 
[...]
Section IV. - Branch (new –SG 53/10; title amend. –SG 97/12)
Art. 77a. (new –SG 53/10; amend. –SG 97/12) (1) One or more European Union lawyers may pursue the profession of lawyer in the Republic of Bulgaria in a branch of a European Union grouping.
(2) In branches under para 1 may be included attorneys individually or jointly with European Union lawyers.
(3) The registration and business of branches under para 1 shall be carried out pursuant to Art. 57, 58 and 60-75, provided that the limitation relating to the number of attorneys set out in Art. 58 shall not apply. [...]
(4) The name of the branch shall include the name of the European Union grouping, the word "branch", the legalstatus of the grouping in the Member State of its origin and at least one of the names of the branch members who are practising the profession of lawyer in the Republic of Bulgaria. [...]" (Attorney Act, SG. 55/25 Jun 2004, as amended)
Attorney Act, SG. 55/25 Jun 2004, last amended 17 February 2021
[<a href="https://justice.government.bg/home/normdoc/2135486731">Act</a>]