What is the Energy Charter Treaty sunset clause, and how long does it last?
The sunset clause is Article 47(3) of the Energy Charter Treaty (ECT). After a state's withdrawal takes effect, the treaty keeps applying to existing investments "for a period of 20 years from such date". Protection runs both ways, for other parties' investors in the leaving state and for its own investors abroad. Our guide to investment treaty arbitration covers how claims are brought.
Under Article 47(2) a withdrawal takes effect one year after the Depositary receives the notice, unless the notice names a later date. Italy shows the arithmetic. Its withdrawal took effect on 1 January 2016, so protection runs to 1 January 2036 on our calculation.
Claims do follow withdrawals, within one limit: protection reaches only investments in place on the effective date. Rockhopper's case against Italy, ICSID Case No. ARB/17/14, was registered on 19 May 2017 and is still pending on resubmission.
Which states have withdrawn from the ECT, and until when can their investors still claim?
Fourteen Contracting Parties have a withdrawal in effect on 10 October 2026, counting the EU and Euratom separately, and six more have given notice. The count comes from the Energy Charter Secretariat's withdrawal notices and country pages such as Italy's; the last column is our own arithmetic, the effective date plus 20 years.
| Party | Withdrawal took effect | Protection runs to (calculated) |
|---|---|---|
| Italy | 1 January 2016 | 1 January 2036 |
| France | 8 December 2023 | 8 December 2043 |
| Germany | 20 December 2023 | 20 December 2043 |
| Poland | 29 December 2023 | 29 December 2043 |
| Luxembourg | 17 June 2024 | 17 June 2044 |
| Slovenia | 14 October 2024 | 14 October 2044 |
| Portugal | 2 February 2025 | 2 February 2045 |
| Spain | 17 April 2025 | 17 April 2045 |
| United Kingdom | 27 April 2025 | 27 April 2045 |
| European Union | 28 June 2025 | 28 June 2045 |
| Euratom | 28 June 2025 | 28 June 2045 |
| Netherlands (European part) | 28 June 2025 | 28 June 2045 |
| Denmark | 4 September 2025 | 4 September 2045 |
| Lithuania | 8 August 2026 | 8 August 2046 |
The Netherlands row covers only the European part, as the Secretariat words it. For the Spanish claims, see our pages on disputes in Spain and renewable energy disputes.
Six more withdrawals are inside their one-year period. Notices went to the Secretariat, interim Depositary since 2 February 2025. Twenty years from each effective date lands in 2047.
| Party | Takes effect |
|---|---|
| Iceland | 17 March 2027 |
| Ireland | 28 April 2027 |
| Romania | 23 May 2027 |
| Bulgaria | 26 August 2027 |
| Moldova | 30 September 2027 |
| Sweden | 7 October 2027 |
Does the sunset clause apply between EU Member States?
The EU and 26 Member States, parties to a 2026 Agreement, say no. Hungary is not a party. We found no tribunal ruling on whether that holds. In Komstroy (C-741/19, 2 September 2021) the Court of Justice of the European Union held that Article 26(2)(c) of the ECT does not apply to intra-EU disputes. A Declaration of 26 June 2024 and an Agreement on the interpretation and application of the ECT, signed in Brussels on 18 February 2026, followed.
Article 2(2) of the Agreement says Article 47(3) "does not extend, and could not have extended at any time" to intra-EU arbitration proceedings. Its parties are 26 Member States and the EU. Hungary is not one of them. The Dutch Treaty Database shows it in force since 25 June 2026 between the parties that have ratified.
The Decision approving the Agreement concedes the point in recital 2: arbitral tribunals "have continued to accept jurisdiction and to issue awards in intra-EU arbitration proceedings".
The Agreement leaves other Contracting Parties' rights untouched, so on our reading of its preamble a UK investor, say, is outside it.
How do sunset clauses work in terminated bilateral investment treaties?
Each bilateral investment treaty (BIT) sets its own survival period. Read the years from the treaty. Within the EU, the 2020 agreement terminating intra-EU BITs ends the sunset clauses of the BITs it lists (Articles 2 and 3). Twenty-three Member States signed it on 5 May 2020, and it has been in force since 29 August 2020.
India shows the other pattern. A Freshfields review, a secondary source, reports sunset clauses in some of the BITs India terminated in 2017. They "continue to protect investments made in India prior to the relevant BIT's termination date". Its example is the India-Portugal BIT, terminated in March 2017, with a 15-year clause. The review does not say a claim was filed. Our page on investment treaty disputes in India gives the wider context.
How can you spot sunset-clause claims before they are filed?
Watch the published withdrawal dates, then the measures that could trigger a claim. The Secretariat posts each withdrawal notice and the end date follows by arithmetic, so the pool of possible claimants is known years ahead. The notice cannot say which of them will sue.
The trigger is a government measure hitting an energy investor. Spain's Royal Decree-Law 9/2013 is dated 12 July 2013, and ICSID registered Eiser's claim (ICSID Case No. ARB/13/36) on 23 December 2013, about five months later. Article 26(1) and (2) adds a three-month amicable settlement step before the investor may choose arbitration.
Registries come late. ICSID's screening takes three weeks on average, and basic case details go online only on registration, after the investor has filed. Our article on the notice of intent in investment arbitration covers the step before filing, and our page on early warning of investment treaty disputes covers the measure that comes first.
What this means for practice
A withdrawal starts a 20-year clock once it takes effect. Italy's runs to 2036; every other end date falls between 2043 and 2047. We think the intra-EU question will matter more than the arithmetic, because it decides who is inside the clock at all.
Monitoring tools such as DSPT Finder surface new government actions several times a day, so a team sees the trigger while the clock is still running. The withdrawal dates come from the Secretariat's public pages.
For the standards a claim rests on, see our guide to the fair and equitable treatment standard and our article on resource nationalism in mining and energy.
Frequently asked questions
What is the Energy Charter Treaty sunset clause?
The sunset clause is Article 47(3) of the Energy Charter Treaty. After a withdrawal takes effect, the treaty keeps applying for 20 years to investments that existed on that day.
How long does ECT protection last after a state withdraws?
Twenty years from the date the withdrawal takes effect, one year after the Depositary receives the notice. Italy's took effect on 1 January 2016, so on our calculation its protection runs to 1 January 2036.
Can investors still bring ECT claims against the UK, Spain or Italy after withdrawal?
The treaty text keeps protection for earlier investments for 20 years. On our calculation that runs to 27 April 2045 for the UK, 17 April 2045 for Spain and 1 January 2036 for Italy. This is not legal advice.
Does the ECT sunset clause apply to claims between EU Member States?
The Member States and the EU say Article 47(3) has no legal effect between EU states, in a 2024 Declaration and a 2026 Agreement. We found no tribunal ruling on that. On our reading, non-EU investors are outside the Agreement.
How can lawyers detect sunset-clause claims before they are filed?
Watch for government measures that hit energy investors in withdrawn states, and check each state's calculated end date. Monitoring tools such as DSPT Finder surface new government actions several times a day, before a registry lists a case.