The law states that appeal procedures are open to the 'affected party'. Article 3 refers to the identity of the interested party, referring to Greek citizens, aliens or legal entities. Especially for Port Services, check also Regulation (EU) 2017/352, Article 18 providing that the Decisions of the Regulatory Authority for Ports  (RAPORTS) may be appealed. Decision 330/2017 establishes the RAPORTS' Regulation for handling complaints. See also: https://www.taxheaven.gr/law/3959/2011 AND http://www.taxheaven.gr/laws/law/index/law/346 