New procedure to resolve “owner unknown” property registrations

A central element of the reform is mandatory cadastral mediation, which will come into force on 16 September 2026. The objective is to resolve some disputes without lengthy court proceedings while, at the same time, ensuring that adverse possession cases reach mediation and, where necessary, the courts with more comprehensive supporting evidence.

Mandatory Stage Prior to Litigation

Pursuant to Article 61, before the relevant action is heard, the claimant is required, under penalty of inadmissibility, to invite the defendants to attend an Initial Mandatory Mediation Session (ΥΑΣ).

The procedure is conducted before an accredited lawyer acting as a cadastral mediator, selected from a special electronic register established and maintained by the Central Mediation Committee.

The interested party must first file with the Land Registry the “basic information sheet,” signed by the cadastral mediator, and pay the prescribed fixed fee. The filing must take place no later than the next working day following submission of the application.

At that point, a critical time limit is triggered: the Initial Mandatory Mediation Session may take place only after at least 30 days have elapsed from the date of registration in the cadastral record. If this time limit is not observed, the mediation agreement is invalid.

The Evidence File Required to Establish 20 Years of Possession

The new procedure significantly raises the evidentiary threshold for claims based on extraordinary adverse possession. The interested party must establish continuous possession of the property for a period of 20 years through a specific combination of tax records, witness statements, and documentary evidence.

It is mandatory to submit an E9 property tax declaration concerning the property in question for a period of at least ten years prior to recourse to mediation, as well as at least two sworn witness statements. These statements must expressly refer to the 20-year period of possession, as well as to the area, location, and boundaries of the property.

In addition, at least two further public or private documents evidencing acts of possession must be submitted.

Acceptable evidence includes electricity, telecommunications, or water bills issued in the name of the interested party; leases in which the interested party is identified as the lessor or receipts evidencing the collection of rent; declarations submitted to public or tax authorities; and building permits.

Topographical plans bearing a certified date, particularly where attached to title deeds, notarial instruments, or building permits, may also be used as evidence. A private agreement for the sale or partition of property may likewise be accepted, provided that it was executed at least 20 years prior to recourse to mediation and bears a certified date.

The cadastral mediator verifies whether the file contains all the required documentation and, if it is complete, incorporates the documents into a single file together with the mediation record, expressly noting this fact therein.

The procedure is thus intended to establish a more standardized evidentiary framework for adverse possession, reducing reliance on cases based exclusively on witness testimony and requiring the interested party to assemble stronger documentary evidence in advance.

The State Is Also Required to Participate

Particular importance attaches to the provisions governing cases in which the parties include the Greek State, local government authorities, or Legal Entities Governed by Public Law.

These entities are now required to participate in the Initial Mandatory Mediation Session. The State is represented by the competent officer of the Legal Council of State, and participation by videoconference is also permitted.

Where the defendant is the State, the parties must be notified in writing by the mediator at least 30 days before the session.

Prior to the session, the competent public authorities are required to submit a document specifying whether the State claims any rights over the property in question.

This provision is particularly significant because failure to submit the document gives rise to a presumption that the State does not assert any rights, while failure to submit it in a timely manner constitutes a specific disciplinary offence on the part of the responsible public official.

When a Case Can Be Resolved Without a Trial

The most significant practical consequence of the reform concerns cases in which the State does not claim the property.

If, during the mediation, the Greek State declares that it asserts no rights over the disputed property, a mediation record may be drawn up stating that the State does not object to the correction of the Land Registry record.

Following its filing with the registry of the competent court, the record is entered in the relevant Land Registry Office, and the registration is corrected, with “extraordinary adverse possession” recorded in the cadastral record as the basis of acquisition.

Before the correction is registered, however, the prescribed declaration of adverse-possession transfer tax must have been submitted, a copy of which must be filed together with the mediation record.

In practice, this provision creates an alternative route for correcting Land Registry records which, where there is no dispute with the State or other interested parties, may substantially reduce the time required for the definitive regularization of title.

Which Properties Are Excluded

The new procedure does not apply to all properties. Property forming part of the public domain or having a public-use or common-use character is excluded.

There is also a specific provision concerning horizontal and vertical properties recorded as “owner unknown.” As a rule, these are subject to an application procedure rather than an action before the courts. However, where the interested party relies on extraordinary adverse possession as the basis of title, the special procedure established by the new law is triggered.

What the Reform Means in Practice for Property Owners

The reform effectively shifts a substantial part of the preparation of a cadastral dispute to the stage preceding court proceedings.

From 16 September, anyone seeking to correct a Land Registry entry recorded as “owner unknown” on the basis of adverse possession will be required to have an organized body of supporting evidence, undergo the mandatory mediation procedure, and have previously registered the required information with the Land Registry.

The new framework may therefore operate in two directions: on the one hand, it tightens the requirements for those seeking to establish ownership of property through adverse possession; on the other, it creates the possibility of faster correction of Land Registry records where there is no genuine dispute concerning ownership.