An investment treaty does not confer jurisdiction over every dispute merely because arbitration is commenced while the treaty is in force. Jurisdiction ratione temporis in investment treaty arbitration determines whether the challenged State conduct and, where the treaty so provides, the dispute itself fall within the treaty’s temporal scope.
Temporal issues commonly arise, for instance, where the investment or part of the challenged conduct predates the treaty, State conduct begins before the treaty enters into force and continues afterwards, the alleged breach consists of a series of measures spanning the relevant date, the treaty excludes pre-existing disputes, or the treaty is terminated before the alleged breach.
The analysis requires more than identifying the dates on which particular events occurred. It begins with the treaty text and turns on the legal characterisation of the alleged conduct and dispute. This note examines the applicable legal framework and its application to continuing and composite acts, pre-existing disputes, provisional application of treaties and the effect of treaty termination and survival clauses.
Jurisdiction Ratione Temporis and the Principle of Non-Retroactivity
The treaty text is the starting point. Its entry-into-force provision, definitions of a protected investor and investment, dispute settlement clause and any express exclusions must be read together.[1]
For instance, some investment treaties expressly protect investments made before they entered into force while excluding disputes that arose before that date.[2] Others apply only to investments made after a specified date or preserve protection for existing investments following termination.[3]
Where the treaty does not expressly resolve the issue, tribunals generally refer to the principle of non-retroactivity reflected in Article 28 of the Vienna Convention on the Law of Treaties (“VCLT”). It states:
Unless a different intention appears from the treaty or is otherwise established, its provisions do not bind a party in relation to any act or fact which took place or any situation which ceased to exist before the date of the entry into force of the treaty with respect to that party.[4]
A related rule governing the temporal element of an internationally wrongful act appears in Article 13 of the International Law Commission’s Articles on Responsibility of States for Internationally Wrongful Acts (“ILC Articles”), which provides that “[a]n act of a State does not constitute a breach of an international obligation unless the State is bound by the obligation in question at the time the act occurs.”[5]
Accordingly, unless the treaty provides otherwise, jurisdiction ratione temporis generally extends to claims based on conduct falling within the treaty’s post-entry temporal scope.[6]
Continuing Breaches, Continuing Effects and Composite Acts
The principle of non-retroactivity does not prevent a tribunal from exercising jurisdiction over the post-entry portion of a continuing breach or over a composite breach that crystallises after the treaty enters into force or the claimant’s acquisition of the investment.[7] It does not, however, make conduct preceding that date independently actionable under the treaty.
Article 14 of the ILC Articles distinguishes a continuing wrongful act from a completed act with continuing effects. A continuing breach extends as long as the conduct continues and remains inconsistent with the relevant obligation.[8] Where conduct begins before a treaty enters into force and continues afterwards, the treaty may apply to the post-entry period, provided that the conduct remains inconsistent with an obligation by which the State is then bound.[9] Pre-entry conduct may provide relevant factual context, but it does not thereby become independently actionable under the treaty.
By contrast, a completed expropriation or other completed measure does not ordinarily acquire a continuing character merely because its effects persist, for example because the investor remains deprived of its property or continues to suffer economic loss.[10] In Mondev International Ltd. v. United States of America, the tribunal expressly distinguished a continuing wrongful act from a completed act whose harmful effects persist. It held that, although pre-NAFTA events or facts may be relevant in determining whether the State subsequently committed a breach, completed pre-NAFTA acts did not become treaty breaches merely because their economic consequences persisted.[11]
Article 15 of the ILC Articles concerns a composite breach constituted by a “series of actions or omissions defined in aggregate as wrongful”. A composite breach occurs when an action or omission, taken together with the preceding conduct, is sufficient to constitute the aggregate wrongful act.[12] The breach extends over the period beginning with the first action or omission in the series and lasts for as long as the relevant conduct is repeated and remains inconsistent with the obligation.[13] Article 15 must nevertheless be read together with the principle of non-retroactivity. Conduct preceding the relevant critical date does not become independently actionable merely because a later measure completes the series.
In Hydro S.r.l. and others v. Republic of Albania, the tribunal reasoned that a series of acts beginning before certain claimants acquired their investments could result in an aggregate breach afterwards. It held that the alleged expropriation crystallised with the seizure decisions adopted in June 2015, which constituted the culmination of the preceding State conduct. The earlier events could therefore be considered as components of the alleged composite breach.[14] By contrast, in LSF-KEB Holdings v. Republic of Korea, the tribunal rejected the composite-breach characterisation because the post-entry conduct was “repetitive, not transformative” and did not complete an aggregate wrongful act having a different legal character from the earlier measures.[15]
Parties alleging a continuing or composite breach should therefore identify the particular post-critical-date conduct that continues the alleged breach or completes the alleged composite act.
Disputes Arising Before a Treaty’s Entry Into Force
Some treaties exclude disputes that arose before they entered into force, even where the investor relies on measures adopted afterwards.[16] In such cases, the tribunal must determine whether the later measures gave rise to a genuinely new dispute or merely confirmed, continued or intensified a controversy that had already crystallised.
In Empresas Lucchetti, S.A. and Lucchetti Perú, S.A. v. Republic of Peru, the Chile-Peru BIT applied to investments made before or after its entry into force but excluded disputes that had arisen earlier. Although the claimants relied on municipal measures adopted after the treaty entered into force, the tribunal found that those measures concerned the same subject matter and had the same “real cause” as an environmental and licensing dispute that had arisen several years earlier. The later measures did not create a new dispute, and the tribunal therefore declined jurisdiction ratione temporis.[17]
Whether a later measure creates a new dispute depends on substance rather than form. A tribunal may consider the parties’ earlier positions, the subject matter of the disagreement, related domestic proceedings and the factual and legal basis of the measures.
Provisional Application
A treaty or some of its provisions may apply provisionally before its formal entry into force under Article 25 of the VCLT.[18] In such cases, tribunals may have jurisdiction ratione temporis as the relevant treaty provisions operate before formal entry into force.[19]
The issue has arisen under Article 45 of the Energy Charter Treaty (“ECT”), which provides for provisional application pending the Treaty’s entry into force, to the extent that it is not inconsistent with a signatory’s constitution, laws or regulations.[20] In Ioannis Kardassopoulos v. Georgia, the tribunal held that the relevant ECT provisions applied to Georgia during the period of provisional application and that it had jurisdiction over claims concerning conduct occurring during that period.[21]
Treaty Termination and Survival Clauses
Under Article 70 of the VCLT, treaty termination ordinarily releases the parties from further performance, unless the treaty or the parties provide otherwise.[22] Investment treaties frequently contain survival or sunset clauses that preserve treaty protection for qualifying investments made before termination, usually for a specified period.
The scope of continued protection depends on the wording of the clause. A survival provision may extend the treaty’s substantive protections and the contracting parties’ consent to arbitration in respect of qualifying investments made before termination.[23] A related temporal issue arises where a successor treaty provides a transitional period for submitting claims under the former treaty.
A recent NAFTA/USMCA case illustrates this. In TC Energy Corporation v. United States of America, the majority held that Annex 14-C of the United States-Mexico-Canada Agreement preserved the right to submit certain legacy investment claims for three years after NAFTA’s termination. It did not, however, extend NAFTA’s substantive obligations to State measures adopted after termination.[24]
An extended period for commencing arbitration therefore does not necessarily extend the period during which State conduct may breach the terminated treaty. It may preserve the right to arbitrate claims arising from pre-termination conduct without creating liability for measures adopted thereafter.
Investors relying on post-termination provisions should therefore carefully distinguish between the continued application of substantive protections and a limited period for submitting claims arising from earlier conduct.
Conclusion
Jurisdiction ratione temporis depends primarily on the temporal scope established by the treaty. The treaty may extend protection to investments made before it enters into force, exclude disputes that arose earlier, or preserve specified protections following termination.
The legal characterisation of the conduct remains decisive. Continuing harm does not, by itself, transform a completed act into a continuing breach, while earlier and later measures may constitute a composite breach only where the applicable obligation is capable of being violated through an aggregate course of conduct. Similarly, a measure adopted after entry into force will not necessarily create a new dispute if it merely continues an earlier controversy, and a survival clause or post-termination filing window will not necessarily extend the treaty’s substantive obligations to post-termination conduct.
A precise chronology is therefore essential, but dates alone do not determine jurisdiction ratione temporis. The tribunal must identify the treaty’s temporal boundaries and determine whether the conduct or dispute relied upon falls within them.
[1] Vienna Convention on the Law of Treaties, opened for signature 23 May 1969, entered into force 27 January 1980, Arts. 31(1)-(2).
[2] See, e.g., Agreement Between the Government of the Republic of Peru and the Government of the Republic of Chile for the Promotion and Reciprocal Protection of Investments, signed 2 February 2000, Art. 2 (Chile-Peru BIT) (unofficial translation) (“This Agreement shall apply to all investments made before or after the entry into force of the Agreement, by investors of one Contracting Party, in accordance with the laws of the other Contracting Party in the territory of the latter. However, it shall not apply to differences or disputes which have arisen prior to its entry into force.”).
[3] See, e.g., Agreement on the Mutual Protection of Investments Between the Government of the Kingdom of Sweden and the Government of the People’s Republic of China, signed 29 March 1982, Arts. 8, 9(3) (applying the Agreement to investments made after 1 July 1979 and preserving Arts. 1-8 for 15 years after termination becomes effective in respect of investments made before that date).
[4] VCLT, Art. 28.
[5] Intl. Law Commission’s Arts. on the Responsibility of States for Internationally Wrongful Acts, Art. 13.
[6] Jus Mundi, Jurisdiction Ratione Temporis, https://jusmundi.com/en/document/publication/en-jurisdiction-ratione-temporis (last accessed 1 August 2026), ¶ 7.
[7] B. Sabahi et al., Investor-State Arbitration (2nd edn., 2019), Ch. XII, ¶¶ 12.12-12.13.
[8] ILC Arts. on State Responsibility, Art. 14 (“1. The breach of an international obligation by an act of a State not having a continuing character occurs at the moment when the act is performed, even if its effects continue. 2. The breach of an international obligation by an act of a State having a continuing character extends over the entire period during which the act continues and remains not in conformity with the international obligation. 3. The breach of an international obligation requiring a State to prevent a given event occurs when the event occurs and extends over the entire period during which the event continues and remains not in conformity with that obligation.”).
[9] ILC Arts. on State Responsibility, Arts. 13, 14(2) and commentary to Art. 14, ¶ 3.
[10] Mondev International Ltd. v. United States of America, ICSID Case No. ARB(AF)/99/2, Award, 11 October 2002, ¶ 58 (“[T]here is a distinction between an act of a continuing character and an act, already completed, which continues to cause loss or damage.”).
[11] Mondev, ¶¶ 57-70. See also Técnicas Medioambientales Tecmed S.A. v. United Mexican States, ICSID Case No. ARB(AF)/00/2, Award, 29 May 2003, ¶¶ 66-70.
[12] ILC Arts. on State Responsibility, Art. 15(1).
[13] ILC Arts. on State Responsibility, Art. 15(2).
[14] Hydro S.r.l. et al. v. Republic of Albania, ICSID Case No. ARB/15/28, Award, 24 April 2019, ¶¶ 558-560, 697.
[15] LSF-KEB Holdings SCA et al. v. Republic of Korea, ICSID Case No. ARB/12/37, Award, 30 August 2022, ¶¶ 354-355. The award was partially annulled on 18 November 2025. The annulment decision has not been published; publicly available official statements indicate that the annulment concerned aspects of the tribunal’s findings on liability and damages.
[16] Chile-Peru BIT, Art. 2 (unofficial translation) (“However, it shall not apply to differences or disputes which have arisen prior to its entry into force.”).
[17] Empresas Lucchetti, S.A. and Lucchetti Perú, S.A. v. Republic of Peru, ICSID Case No. ARB/03/4, Award, 7 February 2005, ¶¶ 48-59.
[18] VCLT, Art. 25 (“A treaty or a part of a treaty is applied provisionally pending its entry into force if: (a) the treaty itself so provides; or (b) the negotiating States have in some other manner so agreed.”).
[19] B. Sabahi et al., Investor-State Arbitration (2nd edn., 2019), Ch. XII, ¶¶ 12.18-12.21.
[20] Energy Charter Treaty, opened for signature 17 December 1994, entered into force 16 April 1998, Art. 45.
[21] See, e.g., Ioannis Kardassopoulos v. Georgia, ICSID Case No. ARB/05/18, Decision on Jurisdiction, 6 July 2007, ¶¶ 203-212, 239-250.
[22] VCLT, Art. 70(1)(a)-(b).
[23] See, e.g., ECT, Art. 47(3) (providing that the Treaty’s provisions continue to apply for 20 years to investments made before a Contracting Party’s withdrawal takes effect).
[24] TC Energy Corporation and TransCanada Pipelines Limited v. United States of America, ICSID Case No. ARB/21/63, Award, 12 July 2024, ¶¶ 146-156, 168-171, 219.