European Union law; private international law; international investment law; international arbitration; international commercial arbitration; investment treaty arbitration; contract-based arbitration; investment contracts; Achmea
Résumé :
[en] The Court of Justice of the European Union (the Court) has famously sought to eliminate intra-European Union (EU) investment arbitration under bilateral investment treaties and the multilateral Energy Charter Treaty. In doing so, the Court has navigated settled case law concerning commercial arbitration. In this regard, Achmea and subsequent rulings are premised upon a distinction drawn by the Court between investment and contract-based arbitration, based on the origin of arbitral proceedings and the intensity of the review of the relevant award. This article demonstrates that this distinction disregards important commonalities and the diversity of enforcement regimes. It is further argued that, even in the light of Achmea, EU law rightly permits intra-EU arbitration under investment contracts, that is, contracts between States and foreign investors. The article thus examines investment contract-based arbitration as the only surviving form of intra-EU investment arbitration and cautions against expansive applications of the Achmea reasoning to contractual agreements, signs of which are already emerging.
1 Case C-284/16 Slovak Republic v Achmea BV EU:C:2018:158 (Achmea);
Case C-741/19 Republic of Moldova v Komstroy LLC EU:C:2021:655 (Komstroy);
Case C-109/20 Poland v PL Holdings Sàrl EU: C:2021:875 (PL Holdings);
Case C-638/19 P Commission v European Food SA EU:C:2022:50 (European Food).
2 Indicatively, see C Contartese and M Andenas, ‘EU Autonomy and Investor–State Dispute Settlement under inter se Agreements between EU Member States: Achmea’ (2019) 56 CMLRev 157;
S Centeno Huerta and N Kuplewatzky, ‘On Achmea, the Autonomy of Union Law, Mutual Trust and What Lies Ahead’ (2019) 4 EurPapers 61;
A Dashwood, ‘Republic of Moldova v Komstroy LLC: Arbitration under Article 26 ECT Outlawed in Intra-EU Disputes by Obiter Dictum’ (2022) 47 ELR 127.
3 Agreement for the termination of Bilateral Investment Treaties between the Member States of the European Union [2020] OJ L169/1 (Termination Agreement).
4 Energy Charter Treaty (adopted 17 December 1994, entered into force 16 April 1998) 2080 UNTS 100 (ECT).
See European Commission (Commission), ‘Declaration on the legal consequences of the judgment of the Court of Justice in Komstroy and common understanding on the non-applicability of Article 26 of the Energy Charter Treaty as a basis for intra-EU arbitration proceedings’ [2024] OJ L (Komstroy Declaration);
cf Government of Hungary, ‘Declaration of the Representative of the Government of Hungary of 26 June 2024 on the Legal Consequences of the Judgment of the Court of Justice in Komstroy and of the Non-Applicability of Article 26 of the Energy Charter Treaty as a Basis for Intra-EU Arbitration Proceedings’ .
The Komstroy Declaration accompanied a formalised agreement between the EU and Member States to the same effect, which is now ‘subject to internal procedures leading to its signature and entry into force’: Commission, ‘EU Notifies Exit from Energy Charter Treaty and Puts an End to Intra-EU Arbitration Proceedings’ (Press Release 28 June 2024) .
5 In the judgments cited in n 1, the Court seems to consider the term ‘commercial arbitration’ broadly, as it referred to case law concerning arbitral proceedings under both commercial and consumer contracts: see especially Case C-126/97 Eco Swiss China Time Ltd v Benetton International NV EU:C:1999:269 (Eco Swiss);
Case C-168/05 Elisa María Mostaza Claro v Centro Móvil Milenium SL EU:C:2006:675 (Mostaza Claro).
6 Achmea (n 1), Komstroy (n 1) and European Food (n 1) concerned investment arbitration under international treaties. The circumstances under which Achmea is relevant to investment arbitration under ad hoc agreements, rather than treaties, will be considered in Section 4, in light of PL Holdings (n 1).
7 Consolidated version of the Treaty on the Functioning of the European Union [2012] OJ C326/47.
8 Case C-567/14 Genentech Inc v Hoechst GmbH and Sanofi-Aventis Deutschland GmbH EU:C:2016:177, Opinion of AG Wathelet, para 67 in conjunction with paras 58, 70.
For a comprehensive discussion of such concerns, see M Penades Fons, ‘The Effectiveness of EU Law and Private Arbitration’ (2020) 57 CMLRev 1069.
9 Case C-116/02 Erich Gasser GmbH v MISAT Srl EU:C:2003:657, paras 48–49, referring to Case C-351/ 89 Overseas Union Insurance Ltd and Deutsche Ruck UK Reinsurance Ltd and Pine Top Insurance Company Ltd v New Hampshire Insurance Company EU:C:1991:279, para 23.
10 Case C-159/02 Gregory Paul Turner v Felix Fareed Ismail Grovit, Harada Ltd and Changepoint SA EU: C:2004:228.
11 With regard to said exclusion in particular, see Case C-190/89 Marc Rich & Co AG v Società Italiana Impianti PA EU:C:1991:319.
12 Case C-185/07 Allianz SpA and Generali Assicurazioni Generali SpA v West Tankers Inc EU:C:2009:69 (West Tankers).
13 Council Regulation (EC) 44/2001 of 22 December 2000 on jurisdiction and the recognition and enforcement of judgments in civil and commercial matters [2001] OJ L12/1 (Brussels I Regulation). This has since been replaced by Regulation (EU) 1215/2012 of the European Parliament and of the Council of 12 December 2012 on jurisdiction and the recognition and enforcement of judgments in civil and commercial matters [2012] OJ L351/1 (Brussels I Regulation Recast).
14 West Tankers (n 12) para 28.
15 West Tankers (n 12), para 30.
16 West Tankers (n 12), para 31.
18 Case 102/81 Nordsee Deutsche Hochseefischerei GmbH v Reederei Mond Hochseefischerei Nordstern AG & Co KG and Reederei Friedrich Busse Hochseefischerei Nordstern AG & Co KG EU:C:1982:107 (Nordsee) para 10.
19 Case 102/81 Nordsee Deutsche Hochseefischerei GmbH v Reederei Mond Hochseefischerei Nordstern AG & Co KG and Reederei Friedrich Busse Hochseefischerei Nordstern AG & Co KG EU:C:1982:107 (Nordsee), para 14.
20 Eco Swiss (n 5) paras 31–41.
21 Eco Swiss (n 5), paras 38–39.
22 Eco Swiss (n 5), para 36.
The classification of EU rules as ‘fundamental’ in this sense may be problematic from a legal certainty perspective: J Basedow, ‘EU Law in International Arbitration: Referrals to the European Court of Justice’ (2015) 32 JIntlArb 367, 373.
23 Case C-40/08 Asturcom Telecomunicaciones SL v Cristina Rodríguez Nogueira EU:C:2009:615.
The judgment relates to arbitration provided for under a consumer, rather than commercial, contract. Both commercial arbitration and consumer arbitration are iterations of contract-based arbitration and, as such, differ from treaty-based investment arbitration.
24 Asturcom ibid, paras 46–48 in conjunction with para 53.
25 Penades Fons (n 8) 1076. In the circumstances of Asturcom ibid, para 53, a breach of EU law could arguably constitute a violation of domestic rules of public policy.
26 See M Bobek, ‘Why There Is No Principle of “Procedural Autonomy” of the Member States’ in HW Micklitz and B De Witte (eds), The European Court of Justice and the Autonomy of the Member States (Intersentia 2012);
regarding time limits, see Case C-188/95 Fantask A/S e.a. v Industriministeriet (Erhvervministeriet) EU:C:1997:321, Opinion of AG Jacobs.
27 Achmea (n 1).
28 Komstroy (n 1).
29 PL Holdings (n 1).
30 Achmea (n 1) para 55;
Komstroy (n 1) para 59.
31 See Mostaza Claro (n 5), as cited in Achmea ibid, para 54.
32 Case C-124/21 P International Skating Union v European Commission EU:C:2022:988, Opinion of AG Rantos, paras 164–165, affirming the General Court in Case T-93/18 International Skating Union v European Commission EU:T:2020:610, para 162.
While the CJEU did not explicitly address Achmea, it considered sports arbitration in light of Nordsee (n 18), Eco Swiss (n 5)
Mostaza Claro Eco Swiss (n 5),
case law concerning commercial and consumer—that is, contract-based—arbitration: Case C-124/21 P International Skating Union v European Commission EU:C:2023:1012, paras 192–193, 198.
33 Achmea (n 1) para 55;
Komstroy (n 1) para 59;
European Food (n 1) para 144.
For a discussion of PL Holdings (n 1), which raises additional, non-treaty issues, see Section 4.
34 Achmea PL Holdings (n 1), para 55;
Komstroy PL Holdings (n 1), para 59;
European Food PL Holdings (n 1), para 144.
35 Achmea PL Holdings (n 1), para 55;
see also, to this effect, PL Holdings (n 1) para 45;
36 States, as parties to the treaty, determine the applicable law. This typically includes international standards of investment protection, such as fair and equitable treatment, but may also include national laws. According to the BIT considered by the CJEU in Achmea ibid, para 4, arbitral tribunals could apply, inter alia, the parties’ national laws and EU law.
37 See generally Y Okada, ‘Can Acta Jure Gestionis Be Attributable to the State? A Restrictive Doctrine of State Responsibility’ (2023) 34 EJIL 383.
38 See eg G Cuniberti, ‘Three Theories of Lex Mercatoria’ (2014) 52 ColumJTransnatlL 369;
H Ciurtin, ‘A Quest for Deterritorialisation: The “New” Lex Mercatoria in International Arbitration’ (2019) 85 Arbitration 123.
39 For the applicability of the 1980 United Nations Convention on Contracts for the International Sale of Goods (CISG) in international arbitration, see G Favero Vaughn and K Duggal, ‘On International Arbitration, Choice of Substantive Law, and the CISG: A Case Law Study’ (2022) 38 ArbIntl 187.
40 Achmea (n 1) para 55;
PL Holdings (n 1) para 45;
41 EU private law, as an obvious example of the salience of EU law in horizontal relationships, is expected to be more relevant in the context of consumer arbitration. An intra-EU commercial dispute which (partly) concerns, for instance, competition rules, data protection, environmental standards, financial regulations or intellectual property rights could also plausibly require the interpretation and application of rules of EU law.
42 See eg the arbitration clause under the BIT considered in Achmea (n 1) para 4.
43 See eg Ioan Micula, Viorel Micula, SC European Food SA, SC Starmill SRL and SC Multipack SRL v Romania, ICSID Case No ARB/05/20, Award (11 December 2013).
44 Achmea (n 1) para 55;
45 Achmea European Food (n 1), para 41; cf paragraphs cited in n 44.
46 Achmea European Food (n 1), paras 34, 58.
For more, see JH Pohl, ‘Intra-EU Investment Arbitration after the Achmea Case: Legal Autonomy Bounded by Mutual Trust?’ (2018) 14 EuConst 767;
Centeno Huerta and Kuplewatzky (n 2).
47 Of course, the Court’s analysis did not end there. Section 3.2 will further examine the importance of ensuring effective judicial review of rendered awards, irrespective of their treaty or contractual basis, insofar as they concern the interpretation or application of EU law.
48 See eg ECT (n 4) art 26(3)(a): ‘each Contracting Party hereby gives its unconditional consent to the submission of a dispute to international arbitration’.
49 J Paulsson, ‘Arbitration Without Privity’ (1995) 10 ICSIDRev 232.
50 Achmea (n 1) para 55;
To this effect, see G Cordero-Moss, ‘Achmea’s Distinction between Investment and Commercial Arbitration’ in A Calissendorff (ed), The Future of Arbitration in Europe (Jure 2020) 25;
S Gáspár-Szilágyi and M Usynin, ‘Does the CJEU Misunderstand Investment Treaty Arbitration in Commission v Micula?’ (2023) 7 EurInvL&ArbRev 53, 59–62.
51 Case C-741/19 Republic of Moldova v Komstroy EU:C:2021:164, Opinion of AG Szpunar, para 60.
52 Republic of Moldova v Komstroy, para 61.
53 ECT (n 4) art 26(2)(a).
54 Komstroy, Opinion of AG Szpunar (n 51) para 61.
55 Komstroy, paras 63–66.
56 Achmea (n 1) paras 34, 58;
PL Holdings (n 1) paras 46, 52, 55.
57 Such arguments posited that these principles precluded the application of clauses, included in international treaties, which provided for arbitration between an investor from one EU Member State against another EU Member State. These fall beyond the scope of the present article. For more, see Pohl (n 46);
58 Achmea (n 1) para 55;
59 United Nations Convention on the Recognition and Enforcement of Foreign Arbitral Awards (adopted 10 June 1958, entered into force 7 June 1959) 330 UNTS 3, art II(3) (New York Convention); Cordero-Moss (n 50) 24.
60 cf Achmea (n 1) para 55;
Komstroy (n 1) para 59: ‘a treaty by which Member States agree to remove from the jurisdiction of their own courts … disputes which may concern the application or interpretation of EU law’;
see also PL Holdings (n 1) para 45;
European Food (n 1) para 139;
International Skating Union EU:T:2020:610 (n 32) para 162.
61 International Skating Union, Opinion of AG Rantos (n 32) paras 164–166.
62 International Skating Union, para 165.
cf Case C-600/23 Royal Football Club Seraing v Fédération Internationale de Football Association (FIFA) and others EU:C:2025:24 (Seraing), Opinion of AG Ćapeta, paras 82–94, who distinguished CAS arbitration under the FIFA Statutes from investment treaty arbitration by adopting a more nuanced rationale.
63 International Skating Union, Opinion of AG Rantos Royal Football Club Seraing v Fédération Internationale de Football Association (FIFA) (emphasis added).
64 As previously explained, such a finding is of course not solely supported by reference to the distinction between commercial and investment arbitration. Rather, the principles of autonomy of the EU legal order and mutual trust between Member States have been more influential in the Court’s reasoning.
65 K Lenaerts, ‘Keynote Speech’ (III LAwTTIP Joint Conference, London, 21 March 2019) .
66 Eco Swiss (n 5) para 35;
Mostaza Claro (n 5) para 34.
67 Eco Swiss (n 5) para 34;
68 Achmea (n 1) para 54;
Komstroy (n 1) para 58.
69 Achmea ibid, para 55;
Komstroy ibid, para 59.
70 Achmea ibid, para 60;
Komstroy ibid, para 66.
71 See Achmea ibid, para 53;
Komstroy ibid, para 57.
72 Opinion 2/13 Union’s Accession to the European Convention on Human Rights EU:C:2014:2454, para 176; Achmea ibid, para 37.
73 The grounds for annulment may differ depending on the jurisdiction but are typically limited. The United Nations Commission on International Trade Law Model Law on International Commercial Arbitration 1985, with amendments as adopted in 2006 (UNICTRAL Model Law), which has been adopted—often modified, by many States—envisages certain grounds to be considered by the competent court at the seat of arbitration, including: the incapacity of a party to the arbitration agreement or invalidity of agreement; the arbitrability of the subject matter of the dispute; or the conflict of the award with public policy; UNCITRAL Model Law, art 34(2).
74 New York Convention (n 59) art V(1)–(2) sets out a closed list of grounds of refusal of recognition and enforcement of awards, for instance relating to the parties’ incapacity, validity of arbitration agreement, composition of the tribunal or consistency with public policy, in light of the relevant applicable national laws.
75 Achmea (n 1) para 54;
76 Consolidated version of the Treaty on European Union [2012] OJ C326/13 (TEU).
ICSID, ‘ICSID Caseload Milestones’ (8 August 2024) .
78 Those brought under the Convention on the Settlement of Investment Disputes between States and Nationals of Other States (adopted 18 March 1965, entered into force 14 October 1966) 575 UNTS 159 (ICSID Convention), as opposed to those under the ICSID Additional Facility Rules (2022) or the ICSID Conciliation Rules (2022), ie 897 cases according to ICSID, ‘The ICSID Caseload—Statistics: Issue 2024-2’ ibid 2.
79 ICSID Convention ibid, art 53(1): ‘The award shall be binding on the parties and shall not be subject to any appeal or to any other remedy except those provided for in this Convention.’ For more, see MB Feldman, ‘The Annulment Proceedings and the Finality of ICSID Arbitral Awards’ (1987) 2 ICSIDRev 85.
80 According to ICSID Convention ibid, art 52(1), the possible grounds of annulment are the following: (a) that the Tribunal was not properly constituted; (b) that the Tribunal has manifestly exceeded its powers; (c) that there was corruption on the part of a member of the Tribunal; (d) that there has been a serious departure from a fundamental rule of procedure; or (e) that the award has failed to state the reasons on which it is based.
81 In all, 158 States have ratified the ICSID Convention, including the UK and 26 EU Member States (Poland is not a State Party). For a full list, see ICSID, ‘Database of ICSID Member States’ .
82 ICSID Convention (n 78) art 54(1).
83 Case C-284/16 Slovak Republic v Achmea BV EU:C:2017:699, Opinion of AG Wathelet, paras 252–253.
84 Case C-284/16 Slovak Republic v Achmea BV EU:C:2017:699, Opinion of AG Wathelet, para 253.
85 See UNCITRAL Arbitration Rules 2021 .
86 See Arbitration Rules of the Arbitration Institute of the Stockholm Chamber of Commerce 2023 .
87 Cordero-Moss (n 50) 21–2.
88 Investment mediation will not be considered in the present article because, notwithstanding questions regarding its compatibility with EU law, mediation is reconciliatory in nature and typically aims at maintaining a good relationship between the parties. See eg ICSID, ‘Background Paper on Investment Mediation’ (12 July 2021) . Investment mediation is therefore not directly comparable to judicial or arbitral proceedings.
89 For more on how treaty and contract-based claims can be reconciled where there is potential overlap, see J Crawford, ‘Treaty and Contract in Investment Arbitration’ (2008) 24 ArbIntl 351.
90 See eg ‘Damages Awards in International Commercial Arbitration: A Study of ICC Awards’ (PwC and Queen Mary University of London 2020) .
91 In particular, it has been suggested that States contract in their private capacity rather than as sovereign entities. See eg E De Brabandere, Investment Treaty Arbitration as Public International Law (CUP 2014) 50–1;
I Marboe and A Reinisch, ‘Contracts between States and Foreign Private Law Persons’ in A Peters (ed), Max Planck Encyclopaedia of Public International Law (OUP 2021).
92 A contractual basis of consent was typically invoked in the early ICSID cases, with treaty-based proceedings proliferating in the 1990s, after Asian Agricultural Products Ltd v Sri Lanka, ICSID Case No ARB/87/3, Award (27 June 1990).
93 For instance, a contractual basis of consent was invoked in 6 per cent of ICSID cases which were registered in the 2024 fiscal year, and 14 per cent of total historical ICSID cases: ICSID, ‘The ICSID Caseload—Statistics: Issue 2024-2’ (n 77) 7–8.
Also, in 2023, the Permanent Court of Arbitration (PCA) provided registry services in 122 investor–State proceedings under international treaties and laws, and in 110 arbitrations ‘arising under contracts involving a State, intergovernmental organization, or other State entity’, though not all of these proceedings concerned claims by investors, let alone foreign investors; PCA, ‘Annual Report 2023’ (PCA 2023) 30 .
94 See eg UNCITRAL Code of Conduct for Arbitrators in International Investment Dispute Resolution 2023, art 1(a) and (b)(iii) .
95 PL Holdings (n 1).
96 PL Holdings (n 1), para 28.
97 PL Holdings (n 1), para 46.
see also Termination Agreement (n 3).
99 PL Holdings ibid, para 47.
100 PL Holding, para 48 and, to this effect, para 65.
101 PL Holding, para 49.
102 PL Holding, para 67 in conjunction with para 65.
103 Achmea (n 1) para 55;
104 Indeed, according to De Brabandere (n 91) and Marboe and Reinisch (n 91), such contracts are often considered as purely private in nature, under international law.
105 To this effect, see Union’s Accession to the European Convention on Human Rights (n 72) paras 191, 194;
Opinion 1/17 EU–Canada Comprehensive Economic and Trade Agreement EU:C:2019:341, paras 128–129.
However, in International Skating Union AG Rantos noted that both Achmea and PL Holdings ‘concerned a (bilateral investment) treaty with a Member State and which related to the principles of mutual trust and sincere cooperation between Member States’ without distinguishing the fundamentally different ways in which they do so: International Skating Union, Opinion of AG Rantos (n 32) para 165.
106 Komstroy, Opinion of AG Szpunar (n 51) para 61.
107 Investment contracts can constitute ‘the most useful tool’ for States to obtain greater environmental and sustainability commitments from foreign investors, even if complementarily to investment treaties: S Faccio, ‘Investment Contracts and the Reform of Investment Arbitration: Towards Sustainability’ (2023) 38 ICSIDRev 625.
For a broader discussion of such arguments, see JW Yackee, ‘Do We Really Need BITs? Toward a Return to Contract International Investment Law’ (2008) 3 AsianJWTO&IntlHealthL&Pol 121.
108 Achmea (n 1) para 54 referring to Eco Swiss (n 5) paras 35, 36, 40; and Mostaza Claro (n 5) paras 34–39.
109 Case C-109/20 Poland v PL Holdings EU:C:2021:321, Opinion of AG Kokott, para 65 in light of para 62.
110 International Skating Union EU:C:2023:1012 (n 32) para 194: ‘In the absence of [sufficient] judicial review, the use of an arbitration mechanism is such as to undermine the protection of rights that subjects of the law derive from the direct effect of EU law and the effective compliance with Articles 101 and 102 TFEU, which must be ensured – and would therefore be ensured in the absence of such a mechanism – by the national rules relating to remedies.’
111 International Skating Union, paras 193, 197, 199.
112 International Skating Union, para 199: ‘Thus, the General Court erred in law by merely finding, in an undifferentiated and abstract manner, that the arbitration rules “may be justified by legitimate interests linked to the specific nature of the sport” … without seeking to ensure that those arbitration rules complied with all the requirements [relating to the effective judicial review of awards] … even though the Commission correctly relied on those requirements in recitals 270 to 277, 282 and 283 of the decision at issue.’
113 Case AT.40208 International Skating Union’s Eligibility Rules, Commission Decision C(2017) 8240 final (8 December 2017) para 271.
114 ibid, para 272.
115 Seraing, Opinion of AG Ćapeta (n 62) paras 76–80, 100–107.
116 Decision No 246/2022 (StE, 9 February 2022).
117 Law No 2338/1995, Government Gazette Issue A, No 202 (14 September 1995) 5651–6137.
118 Decision Nos 582-587/2015 (StE, 25 February 2015) para 5. The StE could only review whether such an award exceeded the jurisdiction of the tribunal in order to determine whether the award was binding. It could not set aside the award or declare it unenforceable, which would ultimately be incumbent upon the Supreme Court (Areios Pagos).
119 Decision No 246/2022 (n 116) para 8.
120 London Court of International Arbitration, Arbitration Rules (2020) .
121 PL Holdings, Opinion of AG Kokott (n 109) para 65. With regard to annulment proceedings, the arbitration agreement in the investment contract considered by the StE renders English law (rather than the law of an EU Member State) as lex arbitri, as London has been selected as the seat of the arbitration. However, the arbitral award considered by the StE was rendered in 2013, while the UK was still an EU Member State.
122 Decision I ZB 12/23 DE:BGH:2023:121023BIZB12.23.0 (German Federal Court of Justice, 12 October 2013) para 25 (unofficial translation).
123 In an extra-EU, and indeed global, context this would amount to a ‘resurgence’, as investment contracts were the preferred mode of investment protection prior to the proliferation of investment treaties: see helpful discussion focusing on the ECT in A Daszko, ‘The Energy Charter Treaty at a Critical Juncture: of Knowns, Unknowns, and Lasting Significance’ (2023) 26 JIEL 720, 722.
