Properties of "unknown owner" with extraordinary use

Under the provisions of Law 5197/2025 and the new legislative initiative of the Ministry of Justice (Special Secretariat for Alternative Dispute Resolution), the scope of land registry mediation is being expanded. The regulation enables citizens to correct, out of court, land registry entries for properties designated as “owner unknown” in cases where ownership rights are asserted on the basis of acquisitive prescription.

According to official data, in 72% of the land registry (out of a total of 3.45 million properties), nearly 9% remain listed as “owner unknown.”

The main changes and the required supporting documents

The new procedure eliminates the need for costly and time-consuming legal disputes, even when the State, local authorities, or public entities do not assert any rights to the property.

📌 Key Stages of the Process

Publicity: Entry in the Land Registry of the Basic Data Sheet for the provision of data, allowing third parties to update or modify the information.

Mediation Proceedings: Conducted by accredited mediators listed in the Special Registry.

Success Protocol: To complete the process, the State/Local Government’s official document stating that no rights are being asserted, as well as the private individual’s supporting documentation, are incorporated into the protocol.

Required Information for Individuals

At least 2 sworn statements

Form E9 filed at least 10 years prior to the hearing

Statements made to public or tax authorities

Building permit & topographic maps with a confirmed date

Private sales/distribution agreement (drafted 20 years ago with a definite date)

Supplementary Supporting Documents

Utility bills (electricity, water, telephone) in the plaintiff's name

Lease agreements or rent receipts

Challenges

Gathering of Supporting Documents: Owners are required to submit sufficient, dated documents covering the required time period (10 to 20 years).

Readiness of the Special Registry: The Special Registry of Cadastral Mediators must be staffed and made operational immediately to avoid further delays.

The expansion of land registry mediation to cases of adverse possession provides an immediate out-of-court solution for thousands of properties with “unknown owners.” The provisions of Law 5197/2025 relieve congestion in the courts, reduce costs for citizens, and enable the safe utilization of real estate assets in the Greek economy.