[2][3] The organisation runs two ships, the Mare Liberum which operates under the German flag, and the sailing yacht, Sebastian K. On 1 May 2023, Mare Liberum was dissolved and ceased operations citing "sabotage, obstruction, and, repression" from the conservative government of Greece and a current impossibility to continue its role safely in observing the border authorities.
[4][5] The Mare Liberum association was able to document a total of 321 incidents between March and December 2020, in which 9,798 refugees were forcibly driven back to Turkey.
The Greek coast guard would have been the main protagonist and, according to survivors, Frontex and NATO were also involved in some cases.
[10][11] At the beginning of September 2020, the Mare Liberum was searched by Greek border guards in Perama on Lesbos.
On September 28, the Greek police announced in a press release that 35 people and four NGOs were being investigated on Lesbos.