On 1 July 2022, the amended Arbitration Rules of the International Centre for Settlement of Investment Disputes (“ICSID” and the “2022 ICSID Rules”) came into effect. The overarching goals of the amendment process, launched in 2016, were to modernise, simplify and streamline the rules, reduce time and cost, and leverage information technology to reduce the environmental footprint of ICSID proceedings (See ICSID Proposals for Amendment of the ICSID Rules – Working Paper #1 2018 (“WP#1”), pp. 1-2). One of the key areas significantly reformed is transparency, where the amendments took a step towards making ICSID proceedings more transparent and open to the public (See Proposed Amendments to the ICSID Regulations and Rules – A Necessary Update). One of the considerations leading to this approach was the need to enhance the public legitimacy of investor-state dispute settlement (“ISDS”) (See WP#1, p. 857). The ISDS regime has been facing criticisms that undermine the legitimacy of the regime as a whole (See UNCITRAL A/CN.9/917, paras. 11-12), also known as the ISDS “legitimacy crisis”. In this context, proponents of increased transparency argued, among other things, that access to case materials enhances public understanding and confidence in ISDS. The 2022 ICSID Rules thus incorporated significant changes relating to the publication of awards, disclosure of third-party funding (“TPF”), and participation in and access to the proceedings.


Transparency is an evolving concept in international arbitration which has no universal definition. In the context of ISDS, transparency primarily relates to public access to the proceedings, including information about the proceedings or generated therein. Transparency is frequently contrasted with the concept of confidentiality, which generally refers to the parties’ obligations not to disclose information concerning the arbitration.

The debate regarding transparency in ISDS is typically traced back to the late 1990s in the context of arbitrations under the North American Free Trade Agreement (“NAFTA”). In order to address the uncertainty with respect to confidentiality and transparency in NAFTA proceedings, in 2001, the NAFTA member States issued a joint statement confirming that there was no general duty of confidentiality under NAFTA Chapter 11 and that, subject to Art. 1137(4) of the same Chapter, nothing precludes the parties from providing public access to documents issued in the proceedings. Building on this development, in 2006, ICSID amended its Arbitration Rules (the “2006 ICSID Rules”) and introduced provisions governing transparency in proceedings with respect to:

    1. publication of awards,
    2.  public attendance at hearings, and
    3.  non-disputing party participation.

Other international investment instruments followed the same approach. In 2014, the United Nations Commission on International Trade Law (“UNCITRAL”) adopted the UNCITRAL Rules on Transparency (the “UNCITRAL Transparency Rules”), which apply to ISDS cases commenced under the UNCITRAL Arbitration Rules (2013), including UNCITRAL cases administered by ICSID.  In 2017, the United Nations Convention on Transparency in Treaty-based Investor-State Arbitration (2014) (the “Mauritius Convention”) entered into force. It provided a mechanism by which ratifying States may apply the UNCITRAL Rules to arbitrations initiated pursuant to investment treaties concluded before 2014. This trend towards greater transparency is also reflected in several international investment agreements (See, e.g., Art. 9.16 and 9.17, 2015 Australia – China Free Trade Agreement; Art. 15(13), 2016 Japan – Kenya Bilateral Investment Treaty (“BIT”); and Art. 19(O), 2019 Belgium – Luxembourg Economic Union Model BIT.

The new provisions on transparency adopted in the 2022 ICSID Rules will apply in ICSID proceedings unless:

    1. the parties agreed otherwise;
    2. the relevant issue is addressed in other applicable instruments, such as the parties’ treaties, contracts, and laws; and/or
    3.  the Mauritius Convention applies.

Publications of Awards

Publication of awards is said to foster greater consistency, cohesiveness, and predictability in case outcomes (See WP#1, p. 857). Access to case law allows parties to better understand the law and predict the outcomes more accurately. It also guides tribunals in developing a “jurisprudence constante” in ISDS. On the other hand, parties to the case may object to the disclosure of sensitive or confidential information regarding their entity.

Art. 48(5) of the ICSID Convention states that awards can only be published with the consent of the parties. The 2006 ICSID Rules add that absent consent, excerpts of the legal reasoning in the award may be published (R48(4)). Notably, these rules did not address orders and decisions other than awards. The 2022 ICSID Rules reversed the starting point, mandating that parties are deemed to have consented to the publication of the award unless a party objects in writing within 60 days after the award has been dispatched (R62). This rule also applies to the publication of orders and decisions, subject to the parties’ redactions (R63).

The deemed consent with an opt-out mechanism under the 2022 ICSID Rules is similar to the recent approach adopted by the International Chamber of Commerce (ICC), according to which the ICC will consider awards and orders for publication by default no less than two years after the award has been notified to the parties. However, parties may object to the publication or require it to be anonymised or pseudonymised (See ICC Note on the Conduct of the Arbitration under the ICC Rules of Arbitration 2021, ¶¶ 58-59). In comparison, the UNCITRAL Rules mandate the publication of awards, including orders and decisions of the tribunal (Art. 3), subject only to exceptions to transparency, which we will discuss further below.

Access to Documents and Hearings

Access to documents and hearings generally contributes to greater transparency in the proceedings and is particularly relevant to disputes involving public interest.

Prior to the amendments, there were no rules in the ICSID mechanism governing the publication of documents submitted by the parties to the tribunal. With regard to hearings, the 2006 ICSID Rules provide that the tribunal may allow the public to attend or observe hearings (R32). In the course of the amendment process, the majority view was that both parties must consent to the publication of documents filed in proceedings, as these types of documents can disclose the party’s strategy and confidential information (See WP#2). Ultimately, the 2022 ICSID Rules introduced an obligation to publish any written submissions or supporting documents filed by either party, provided the parties consent to publication and agree on any redactions (R64). In addition, the 2022 ICSID Rules provide that, unless either party objects, the tribunal must allow persons in addition to the parties to observe hearings (R65). A party may also request the publication of recordings or transcripts of the hearings. Unlike publication of awards, decisions and orders, there is no deemed consent for publication of documents submitted to tribunals and hearing transcripts. Nonetheless, the tribunal must ensure that no confidential or protected information is disclosed (R66).

In comparison, the UNCITRAL Rules mandate the publication of a comprehensive list of documents and do not distinguish between documents issued by the tribunal and those submitted to it (Art. 3). As for hearings, the UNCITRAL Rules are similar to the ICSID Rules as they provide that hearings must be public, subject to certain exceptions (Art. 6), including with respect to confidential or protected information and information that would jeopardise the integrity of the arbitral process (Art. 7).

Disclosure of Third-Party Funding

The increase of TPF in international disputes has made it the subject of recent ISDS reforms (See, e.g., UNCITRAL WGIII, including TPF as one of the reform options). Disclosure of TPF could have an impact on the proceedings, including with respect to conflicts of interest, requests for security for costs against a funded party, and the jurisdiction of the tribunal where the third-party funder was heavily involved in the case (See e.g., Muhammet Çap & Sehil v. Turkmenistan, Teinver v. Argentina). In response to these concerns, arbitral institutions have introduced rules reflecting a trend towards disclosure obligations regarding TPF (See, e.g., Rules 24(l), 2017 Singapore International Arbitration Centre (SIAC) Investment Rules; Rule 44, 2018 Hong Kong International Arbitration Centre (HKIAC) Arbitration Rules; and Article 11(7), 2021 ICC Arbitration Rules).

The provision on TPF (R14) is perhaps the most significant change related to transparency under the 2022 ICSID Rules. In addition to introducing an all-encompassing definition of TPF, the 2022 ICSID Rules mandate an ongoing disclosure obligation on the funded party (which does not require an order from the tribunal), including with respect to the funder’s ultimate beneficial owner. The disclosure obligation is triggered by the registration of the request for arbitration or “immediately” upon conclusion of the TPF agreement after the request for arbitration.

While certain other institutional rules include provisions with respect to TPF, none of them are as broad as the TPF provisions set out in the 2022 ICSID Rules. For instance, as regards the disclosure obligation, under the SIAC Investment Rules, the funded party is only obliged to disclose the TPF arrangement if the tribunal orders such disclosure (Art. 24(l)). As regards the timing of the disclosure, the ICC Rules require the funded party to disclose the existence and identity of any TPF “promptly”, a term which is not defined. Notably, the UNCITRAL Rules do not contain any provisions on TPF.

Participation by Third Persons and Non-disputing Parties

In ISDS, a non-disputing party (“NDP”), often called amicus curiae, refers to any third party that intervenes in the proceedings to assist the tribunal regarding some aspects of a case. To date, tribunals have granted participation of NDPs such as non-governmental and non-profit organisations, mostly in cases involving public interest.

Under the 2006 ICSID Rules, the tribunal may allow submissions from NDPs after considering a non-exhaustive list of factors, including how they would assist in the determination of an issue, whether they would address a matter within the scope of the dispute and whether the non-disputing party has a significant interest in the proceeding (R37(2)). The 2022 ICSID Rules have expanded the list and included an obligation for the tribunal to provide relevant documents to the non-disputing party unless a party objects (R67). Notably, the 2022 ICSID Rules clarified the distinction between NDPs and “non-disputing Treaty parties” (“NDTPs”). The latter are given the opportunity to make a submission on the interpretation of the treaty at issue in the dispute as a matter of right, and the tribunal may invite their submission after consultation with parties (R68).

The same distinction—albeit using different terms (i.e.,third persons” and “non-disputing parties to the treaty”)—is present under the UNCITRAL Rules (Art. 4 and 5). Here, the factors that need to be considered by the tribunal in admitting submissions from NDPs are largely the same as those under the 2022 ICSID Rules. However, compared to the 2022 ICSID Rules, the UNCITRAL Rules are wider in scope as they allow admission of submissions from NDTPs “on further matters within the scope of the dispute” (Art. 5(2)).

Is Enhanced Transparency the way Forward?

The current landscape of ISDS is undoubtedly moving towards greater transparency. Whether enhanced transparency would be the panacea to the legitimacy crisis is a question that may be tested as we welcome ongoing reforms and initiatives on transparency.

ICSID has recently recorded the highest number of cases registered within a year – 66 cases in 2021, following the previous high of 58 cases in 2020. Although ISDS is not limited to the ICSID framework, the consistent increase in ICSID’s caseload demonstrates that ISDS still appears to be an attractive mechanism for investment disputes despite criticisms in relation to its legitimacy. The 2022 ICSID Rules are thus a welcomed development in addressing the so-called “legitimacy crisis”. As noted by the tribunal in Vivendi, “public acceptance of the legitimacy of international arbitral processes, particularly when they involve states and matters of public interest, is strengthened by increased openness and increased knowledge as to how these processes function” (para. 22).


Svetlana Portman is an Associate in the International Dispute Resolution Group of Debevoise & Plimpton. She represents private clients and states across multiple jurisdictions in investor-state and international commercial arbitrations governed by various substantive laws and conducted under the auspices of the major arbitral rules. 

Nusaybah Muti is an Intern in the International Dispute Resolution Group of Debevoise & Plimpton. She is a Philippine-qualified lawyer with a growing experience in investor-state and international commercial arbitrations. She holds an LL.M. in Transnational Arbitration and Dispute Settlement degree from Sciences Po Paris and previously completed internships at ICSID and Mayer Brown.