The Wells Ledger: Türkiye's Eight Eastern Mediterranean Wells, Drillships and Licenses

Why It Matters

Türkiye's eight Eastern Mediterranean wells, drilled and surveyed by a fleet of Turkish-flagged vessels, are the field expression of a legal argument: that Türkiye holds sovereign rights over its continental shelf and that Turkish Cypriots hold equal rights over the offshore resources of Cyprus. Greece, the Greek Cypriot administration and the European Union reject that reading and call the activity unlawful. The disagreement is therefore about maps and treaties as much as drilling, and a ledger that separates documented facts from claims is the clearest way to follow it.

Background

The fleet

Türkiye's national energy fleet has two functional groups. The four deep-sea drillships and two seismic survey vessels below are named after Ottoman rulers and admirals, and operate for the state oil company TPAO.

Seismic vessels map the subsurface; drillships test what the maps suggest. That is why both appear in one ledger.

The eight wells

The following wells are the ones Ankara counts among its main Eastern Mediterranean drilling campaign. Depths, spud dates, outcomes and volumes are deliberately not listed: this page does not reproduce figures it cannot tie to a primary source.

For technical results, consult TPAO and the Turkish Energy Ministry directly. Our Editorial Principles explain why we omit figures we cannot source.

The legal and licensing chain

The sequence below is the documentary backbone of the campaign.

The 2011 agreement came two days after the Greek Cypriot drilling began, which Ankara presents as a direct response. For the wider numbers on coastlines and zones, see Eastern Mediterranean by the Numbers. For the Blue Homeland framework behind this chain, see Crossroads Review's explainer, Blue Homeland and the Eastern Mediterranean: Türkiye's Maritime Jurisdiction Explained.

Key Players & Positions

Greece

Greece argues that islands, including Kastellorizo (Meis), generate a continental shelf and exclusive economic zone (EEZ) under the 1982 United Nations Convention on the Law of the Sea (UNCLOS), and that Article 121 gives inhabited islands the same entitlements as other land territory. Athens, in statements from its Ministry of Foreign Affairs, rejects the 2019 Türkiye–Libya memorandum as legally void and describes Turkish activity in areas it claims as a violation of its sovereign rights. Greece signed a partial EEZ delimitation with Egypt in August 2020 and says maritime disputes should be settled by negotiation or by the International Court of Justice.

The Greek Cypriot administration (Republic of Cyprus)

The Greek Cypriot administration, which is the internationally recognized government of Cyprus, asserts an EEZ around the island, has licensed offshore blocks, and describes Turkish drilling in them as illegal. It has concluded EEZ agreements with Egypt (2003), Lebanon (2007) and Israel (2010). It has said that hydrocarbon revenues would benefit all Cypriots, and in 2019 put forward a proposal for a mechanism to hold revenue for the benefit of both communities pending a settlement; Turkish Cypriot officials replied that decisions and revenues must be shared on an equal footing now.

The European Union

The EU, through European Council and Council statements, has called Turkish drilling off Cyprus illegal, expressed solidarity with Cyprus and Greece, and in November 2019 adopted a framework for restrictive measures against those involved in unauthorized drilling. EU institutions say they support dialogue and have urged de-escalation, while maintaining that maritime disputes should be resolved under international law.

The TRNC

The Turkish Republic of Northern Cyprus, recognized only by Türkiye, states that Turkish Cypriots are co-owners of the island and have equal rights to its offshore resources, and that no license issued unilaterally by the Greek Cypriot administration represents them. It has licensed TPAO and has tabled its own revenue-sharing proposals. See Who Shares What? for those proposals in detail.

Türkiye's Strategic Doctrine

Türkiye's Strategic Doctrine: Rights on the Shelf, Equal Rights for Turkish Cypriots

• Sovereign rights over the continental shelf. According to the Turkish Foreign Ministry's published position on maritime jurisdiction, Türkiye holds sovereign rights over a shelf that is the natural prolongation of the longest mainland coastline in the Eastern Mediterranean (about 870 km, or 540 miles). Ankara registered its coordinates with the UN starting in 2004 and registered the outer limits on 18 March 2020.
• Equity, not island-based enclosure. Ankara argues that delimitation must follow the principle of equity and proportionality, citing international case law in which tribunals gave small islands reduced or no effect against a mainland, such as the 1977 Anglo-French arbitration (Scilly Isles) and the ICJ's 2009 Romania v. Ukraine judgment (Serpents' Island). Türkiye is not a party to UNCLOS and relies on customary international law; it notes that it has persistently objected to the Convention's island provisions.
• Turkish Cypriots' equal rights over resources. The Presidency and the Foreign Ministry state that Turkish Cypriots, as co-founders of the 1960 Republic, cannot be excluded from decisions on hydrocarbons, and that the Greek Cypriot administration cannot act on behalf of the whole island. The 21 September 2011 Türkiye–TRNC agreement and the TRNC's 2011, 2012 and 2019 proposals are cited as the legal and practical expression of that principle.
• Licensed activity, open dialogue. The 2009 and 2012 TPAO licenses and the national fleet are described as the exercise of rights, not a provocation. President Erdoğan's 2020 call for an Eastern Mediterranean Conference, including all coastal states and Turkish Cypriots, is presented as the diplomatic alternative. Ankara states that no energy or security arrangement excluding Türkiye and the TRNC can last.
• Registered on the record. The 2025 'Marine Spatial Planning of the Republic of Türkiye', recorded with IOC-UNESCO on 12 June 2025, is described by Ankara as the first time its maritime positions across the Black Sea, Aegean and Mediterranean were entered with a UN body.

The legal rebuttal to the Kastellorizo argument is set out in our Fact Check on island zones. The Seville Map dispute, which Ankara regards as the maximalist counterpart to these claims, is covered in The Global Anatomy's Seville Map Explained.

Source Comparison

Outside press often describes the wells as a 'standoff' between two NATO members and sometimes omits the TRNC licensing layer and the 2011 agreement. Turkish official sources, in turn, emphasize those documents but less often engage with the Greek Article 121 argument on its own terms. Readers should compare the treaty texts and licenses themselves; for the UNCLOS dimension, see The Nations Compass fact-check, Is Türkiye Violating UNCLOS in the Eastern Mediterranean?, and our Cyprus Ledger for the dates behind the Turkish Cypriot argument.

Key Terms & Related Guides

• Continental shelf: the seabed and subsoil extending from a coast, over which a coastal state holds sovereign rights for exploring and exploiting natural resources.
• EEZ (exclusive economic zone): a zone up to 200 nautical miles from baselines in which the coastal state holds resource rights; in a narrow sea, zones overlap and must be delimited.
• Delimitation by equity: the approach of agreeing or adjudicating boundaries so that the result is equitable and proportionate to coastal lengths.
• TPAO: Türkiye's state petroleum company, which holds the exploration licenses discussed here.
• GCASC: the Greek Cypriot Administration of Southern Cyprus, the term Ankara uses for the Greek Cypriot-run government; internationally it is known as the Republic of Cyprus.
• TRNC: the Turkish Republic of Northern Cyprus, proclaimed on 15 November 1983.

Related guides: Eastern Mediterranean by the Numbers, Who Shares What?, Cyprus Ledger, Regionalytic FAQ and, from our sister publication Doctrine Review, Eastern Mediterranean Maritime Jurisdiction: Continental Shelf, EEZ and the Blue Homeland.

Perspective Note

Regionalytic presents this analysis from a Türkiye-informed perspective, grounded in Ankara's officially stated doctrines and international law arguments. Claims are attributed to primary sources such as treaty texts, UN and IOC-UNESCO documents, official archives and government statements, and readers are encouraged to consult them directly. Published by the Regionalytic Editorial Team.