The establishment of a branch of a third country insurance company requires a license issued by the Supervisory Authority on the basis of reciprocity.
"Article 2 - Scope of use of the term insurer (Article 2 of Directive 2009/138 / EC)
1 . The provisions of this law apply:
(a) to reinsurance undertakings established in Greece, or wishing to acquire a registered office in Greece, for all life and non-life insurance undertakings which they carry out within the European Union, whether under establishment or freedom to provide services;
(b) to reinsurance undertakings; and who carry out only reinsurance activities, established in Greece, or who wish to acquire a seat in Greece, for all reinsurance operations carried out within the European Union, either under the status of establishment or freedom to provide services, with the exception of the provisions of Part Four currently,
c) insurance and reinsurance undertakings established in a third country operating in Greece, under the provisions of Chapter I of this Part,
d) insurance and reinsurance undertakings established in any Member State of the European Union operating in Greece either under establishment or under the freedom to provide services, in accordance with the provisions of Chapter H of this Part.
[...]
Article 115
Conditions for establishing a branch (Articles 145 and 146 of Directive 2009/138 / EC) [...]
3 . Insurance undertaking established in another Member State may establish a branch in Greece, where the supervisor of origin notify the Supervisory Authority the following information and documents:
a) the business plan, in which at least have the types of business envisaged and the administrative organization of the branch,
(b) a power of attorney for the appointment of a legal representative within the meaning of Article 261 [...]
(c) an address in Greece to which documents will be requested and delivered, including notifications addressed to the legal representative [...]
e) the certification that the insurance company meets the requirements of the Solvency Capital Requirement and the Minimum Capital Requirement of 12 2009/138 / EC.
[...]
Article 130 - Authorization principles and conditions (Article 162 of Directive 2009/138 / EC)
1 . The exercise of direct insurance in Greece by a third country company requires a license issued by the Supervisory Authority to the applicant insurance company, in accordance with the principle of reciprocity and provided that the company meets at least the following conditions:
a) has a license to exercise insurance under the law of its registered office and for the branches that apply for a license to conduct insurance operations in Greece,
b) establishes a branch in Greece,  [...]" (Law on private insurance (4364/2016), subsequently amended, Articles 2, 115 and 130 [google translation based on unofficial text at kodiko.gr])
Law on private insurance (4364/2016), subsequently amended, Articles 2, 115 and 130
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