R v. C

HCCT 126/2025

[2026] HKCFI 4688

IN THE HIGH COURT OF THE

HONG KONG SPECIAL ADMINISTRATIVE REGION

COURT OF FIRST INSTANCE

CONSTRUCTION AND ARBITRATION PROCEEDINGS

NO 126 OF 2025

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J U D G M E N T

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1.Introduction

1.1The Plaintiff (“R”) commenced these proceedings by an originating summons dated 2 September 2025 (“OS”) pursuant to section 26 of the Arbitration Ordinance Cap 609 (“AO”). By the OS, R requests the court to decide its challenge (“Challenge”) against the appointment of  XXXX XXX XXX XXX (“SS”) as an arbitrator in an arbitration (“BIT Arbitration”) administered by the Hong Kong International Arbitration (“HKIAC”) under the 2024 Administered Arbitration Rules (“HKIAC Rules”). The Challenge was previously dismissed on 14 August 2025 by the Proceedings Committee of the HKIAC (“Proceedings Committee”) for the reasons contained in the Recommendation on Challenge dated 13 August 2025 (“Recommendation”).

1.2At the hearing, I was ably assisted by Mr Charles Manzoni SC (leading Mr Elson Tong) for R and Mr Simon Chapman (together with Mr Antony Crockett) for the Defendant (“C”).

2.Background

2.1C is a corporation organized under the laws of XXXXX. R is a sovereign state. The dispute between the parties relates to C’s majority shareholding in XXXXX XXXXX XXXXX XXXXX XXXXX XXXXX XXXXX XXXXX XXXXX XXXXX XXXXXXX. It is C’s case that it suffered and continues to suffer loss and damage as a result of R’s violation of its obligations under (1) an agreement titled “XXXXX XXXXX XXXXX XXXXX XXXXX XXXXX XXXXX XXXXX XXXXX XXXXX XXXXX XXXXX XXXXX XXXXX XXX XXXX XXXXX”[1] (“BIT”) and (2) the Energy Charter Treaty (“ECT”).

2.2On 31 October 2024, C commenced 2 sets of arbitral proceedings against R. One is premised on R’s alleged breaches of its obligations under the BIT, ie the BIT Arbitration, and the other on R’s alleged breaches under the ECT (“ECT Arbitration”). As described in R’s evidence, in the two parallel arbitrations, C challenges various measures that R adopted in XXXXX XXXXX XXXXX XXXXX XXXXX XXXXX XXXXX XXXXX which have allegedly harmed C. One such measure is XXXXX XXXXX XXXXX XXXXX XXXXX XXXXX XXXXX XXXXX XXXXX XXXXX XXXXX XXXXX XXXXXXXX. In both arbitrations, it is alleged that (1) C’s majority shareholding in XXXXX was subjected to temporary management since XXXXXXX, (2) pursuant to R’s instructions and/or directions, motions were passed not to distribute XXXX’s dividends and to keep the net profit in the amount of approximately XXXXXXXXXX at the disposal of XXX and (3) R is intending to continue to deprive C of its rights as a foreign investor and R is not intending to return XXX to C. In the notices of arbitration commencing the BIT Arbitration (“BIT NOA”) and the ECT Arbitration (“ECT NOA”), C has quantified its monetary claim to be no less than XXXXXXX.

2.3SS is the arbitrator appointed by C in the BIT Arbitration and was the arbitrator appointed by C (until his removal set out below) in the ECT Arbitration. In addition to the BIT Arbitration and the ECT Arbitration, SS has also been appointed by another claimant, X X X X X X X X X X (“X X X”) against R brought in February 2024 (“X X X X Arbitration”). The X X X Arbitration is another investment treaty arbitration but governed by different treaties[2].

2.4X X X was until 2022 the parent company of C and C has since then been owned as to 99% by X X X X.

2.5In both the BIT NOA and the ECT NOA: (1) C provided 5 addresses of R for the purpose of service of the NOAs, 4 of them in X X  (including that of the Ministry of Foreign Affairs) and the other that of R’s embassy in X X X, X X X X X and (2) C proposed to appoint SS as an arbitrator.

2.6As a matter of chronology:

(1)  The BIT NOA and ECT NOA were received by R’s embassy on 4 November 2024;

(2)  SS accepted his appointments and made disclosures on 19 November 2024;

(3)  The BIT NOA and the ECT NOA were received by the Ministry of Foreign Affairs in X X X on 12 November 2024;

(4)  R sought to challenge the appointments of SS in the BIT Arbitration and the ECT Arbitration on 26 November 2024.

2.7The challenges against the appointments of SS in the BIT Arbitration and the ECT Arbitration took very different routes. Whereas the parties, at the latest by February 2025, were able to agree on how the challenge in the ECT Arbitration was to be determined, the parties were unable to do so in respect of the Challenge until sometime in April 2025 for the following reasons:

(1)  Although BIT Article 10 contains an arbitration agreement, it only provides that either party to a dispute is entitled to refer the dispute to an international arbitral tribunal. Whilst BIT Article X X X provides that each party to the dispute, unless otherwise agreed, may request the Chairman of the Institute of Arbitration of the Stockholm Chamber of Commerce (“SCC”) to appoint arbitrators, it does not specify where, by whom or how a challenge against an arbitrator is to be decided;

(2)  In respect of the Challenge, the “lacuna” set out above gave rise to procedural disagreements on how the Challenge was to be determined;

(3)  Initially, on 28 January 2025, C notified R that it would request the SCC to determine the Challenge;

(4)  On 30 January 2025, R indicated that it did not agree with C’s proposal and requested instead for an arrangement similar to that for the challenge in the ECT Arbitration, namely for the Challenge to be determined by an appointing authority designated by the Permanent Court of Arbitration;

(5)  On 6 February 2025, R agreed that it would permit an individual of the SCC Board to decide the Challenge, but the parties failed to agree on a member of the SCC Board to decide the Challenge;

(6)  Notwithstanding the disagreement, on 18 March 2025, C requested the Chairman of the SCC Board to decide the Challenge, with which request R disagreed;

(7)  On 28 March 2025, the Chairman of the SCC Board determined that he did not lack jurisdiction to make a decision on the Challenge;

(8)  On 3 April 2025, the SCC reiterated that its decision was final and that its decision on jurisdiction remained;

(9)  On 7 April 2025, R informed the SCC that it was minded to commence court proceedings to enjoin the SCC from proceeding to entertain the Challenge;

(10)  On 9 April 2025, to facilitate resolution of the disagreements arising from the “lacuna”, R and C entered in a procedural agreement (“Procedural Agreement”) specifying, inter alia, that (1) the BIT Arbitration would be administered by the HKIAC and seated in Hong Kong and (2) the Challenge would be decided by the HKIAC instead of the SCC.

2.8C relies on the matters set out in the preceding two paragraphs to mount two preliminary challenges. First, it is said that, the BIT NOA having been received by the R’s embassy on 4 November 2024, the Challenge brought only on 26 November 2024 was out of time as it was brought beyond the 15-day time limit stipulated by either the 1976 UNICITRAL Arbitration Rules (“UNCITRAL Rules”) or the HKIAC Rules (“Time-Bar Argument”). Secondly, C contends that R’s grounds in support of the Challenge are either waived or barred by estoppel by the terms of the Procedural Agreement (“Waiver and Estoppel Argument”).

2.9In relation to the challenge in the ECT Arbitration, that challenge, as noted above, was dealt with by an appointing authority designated by the Permanent Court of Arbitration, and on 16 May 2025, the appointing authority upheld R’s challenge against SS on the basis that his concurrent service as an arbitrator in both the BIT Arbitration and the ECT Arbitration would give rise to justifiable doubts as to SS’s impartiality (“ECT Challenge Decision”). It is common ground that SS has since been removed as an arbitrator in the ECT Arbitration.

3.Overview of R’s grounds

3.1As noted at Recommendation §48, R relies on the following grounds in support of the Challenge against the appointment of SS:

(1)  The positions adumbrated in his writings on Most Favoured Nation (“MFN”) clauses (“Prejudgment Ground”);

(2)  His multiple appointments in cases against R, ie the BIT Arbitration, the ECT Arbitration and the X X Arbitration (“Multiple Appointments Ground”);

(3)  His connection to X X X X (“Nationality Ground”).

3.2Mr Manzoni contends that the above grounds, whether individually or cumulatively, give rise to justifiable doubts as to SS’s impartiality or independence with the meaning of section 25 of the AO.  

(i)  Prejudgment Ground

3.3In order to understand the Prejudgment Ground, it is necessary to identify the relevance of MFN clauses in the BIT Arbitration.

3.4BIT Article 3 is the relevant MFN provision. It provides:

“(1) Each Contracting Party shall accord in its territory, to investments made by investors of the other Contracting Party, treatment that is no less favourable than that which it accords to investments made by investors of third States.

(2) Each Contracting Party shall accord in its territory, to investors of the other Contracting Party, in respect of their activities in connection with such investments, treatment that is no less favourable than that which it accords to investors of third States.”

3.5BIT Article X X is the dispute resolution clause and provides as follows:

“X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X”

3.6It is R’s evidence that, in the BIT Arbitration, C seeks to arbitrate claims that R contends are not covered by BIT Article X X. These include C’s claim that (1) R expropriated C’s investment (distinct from claims regarding the amount of compensation due or method of its payment set out in Article X X), (2) R violated BIT’s provisions on (a) fair and equitable treatment, (b) full protection and security and (c) non-discrimination and (3) R breached the non-impairment obligation which does not exist in the BIT. R points out that it is C’s case that C is entitled to import substantive protections and jurisdiction in other investment treaties signed between R and other states by virtue of BIT Article 3.

3.7The foregoing may be illustrated by, for example, the following averments in the BIT NOA:

(1)  §86: “[R] is obliged not to "impair by unreasonable or discriminatory measures the management, maintenance, use, enjoyment or disposal of investments in its territory" ("Non-Impairment Clause") in accordance with Article 2(2) of the  X X X X X X X X X, which is applicable to [C] and its Investment by virtue of Article 3 of the BIT”;

(2)  §§125-126: “Therefore, Article 3 of the BIT allows [C] to rely on the "treatment" that [R] accords to investments of other foreign investors with respect to the standing offer to arbitrate disputes over breaches of any substantive protections…. Hence, binding agreement to arbitrate can also be derived from arbitration agreements such as in Article 8 of the Agreement between the Government of X X X X X X X X X and the Government of [R] concerning the Promotion and Reciprocal Protection of Investments…”.

3.8Significantly, it is averred at BIT NOA §124 that:

“[BIT Article 3(1)] seeks to prevent discrimination of investors from certain states, which were afforded less favourable conditions than investors from other states. The BIT uses the term "treatment". Access to an investor-state dispute settlement mechanism to address alleged violations of the BIT's substantive protections is also "treatment" by a host state. It is well established in investment treaty jurisprudence that [BIT Article 3(1)] applies in this manner. The submission of an investment dispute to arbitration forms a highly relevant part of the protection for investors by granting them the corresponding procedural options, in the case of violation of their substantive rights.” (emphasis added)

3.9The footnote of BIT NOA §124 refers to a number of authorities, most notably Roslnvest Co Ltd v Russian Federation, SCC Case No V(079/2005) and Emilio Augustin Maffezini v Spain, ICSID Case No ARB/97/7.

3.10As observed in an article in Global Arbitration Review (2025) titled “Substantive Protections: MFN jurisprudence explained through an analysis of treaty language, the claimant’s ambition and choice of arbitrator” (“GAR Article”), the investment treaty jurisprudence referred to at BOT NOA §124 is by no means “well established”. Whilst C’s position is supported by the Maffezini line of authorities, there is a contrary line of authorities led by Plama Consortium Limited v Republic of Bulgaria, ICSID Case No ARB/03/24. The GAR Article observes as follows:

“While the jurisprudence regarding the application of MFN clauses to substantive rights has been largely consistent and predictable, much greater variance has been observed in decisions regarding the application of MFN clauses to procedural rights and obligations. The divergence traces its roots back to the Maffezini v Spain (2000) decision in which the tribunal took the view that the MFN clause in the Argentina-Spain BIT applied to procedural rights… The tribunal based its decision primarily on its interpretation of the terms of the clause and the importance investors attach to the procedural rights extended to them under investment treaties…

However, the International Centre for Settlement of Investment Disputes (ICSID) tribunal in Plama v Bulgaria (2005) took a fundamentally different conceptual approach… The Plama Tribunal rejected the claim, concluding that the ability to expand a tribunal's jurisdiction through an MFN clause cannot be implied but must be stated expressly…

The debate as to which tribunal’s approach is more appropriate continues more than 20 years after the Maffezini and Plama decisions. The dividing line between the tribunals that have applied MFN to procedural rights (following Maffezini) and an even greater number that have rejected that premise (like the Plama tribunal) can be seen across some 54 decisions.”

3.11That there is a divergence between the Maffezini and Plama lines of cases (“Maffezini-Plama Divergence”) is recognized by SS, who has described the divergence as a “schism” in his writing titled “X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X (“Article No 8”).

3.12Mr Manzoni has described (1) BIT Article 3 as a neutrally worded clause as it neither expressly allows nor expressly prohibits the importation of substantive protection or arbitral jurisdiction from other treaties, and (2) as a consequence, the divergence as a “key outcome-determinative” issue.

3.13As pointed out by Mr Chapman, the foregoing may have mischaracterized BIT Article 3 and as a result overstated the importance of the divergence. Mr Chapman says that (1) it is C’s primary case that BIT Article X X allows for the question of expropriation (and not only that of the amount of compensation) to be arbitrated and (2) in any event, BIT Article 3, when read with the other provisions in the BIT, is not a neutrally worded clause. In the foregoing regard, Mr Chapman’s propositions are premised on BIT Article X X to which BIT Article X X refers[3]. It provides as follows:

“X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X”

3.14Irrespective of whether the Maffezini-Plama Divergence is a “key outcome-determinative” issue, I do not understand Mr Chapman to have submitted that it is a peripheral or unimportant issue.

3.15Where the divergence is or should be considered a significant issue in the BIT Arbitration, it is R’s case that the Prejudgment Ground is made out for 3 reasons, in that SS’s writings have demonstrated that:

(1)  SS has consistently opined that neutrally worded MFN clauses should be uniformly interpreted in favour of importing provisions in other BITs;

(2)  SS is ideologically committed to arbitrators acting as international “lawmakers”;

(3)  SS understands the importance of arbitrators signaling their predisposition.

(ii)  Multiple Appointments Ground

3.16Whilst SS has been removed as arbitrator in the ECT Arbitration, R argues that SS’s continued appointment in the X X X Arbitration gives rise to the appearance that he would receive information that improperly influences his considerations in the BIT Arbitration. This is because both cases involve claims by companies relating to their investments in energy and power in R through shareholdings in local R energy companies; both challenge R’s governmental measures such as X X X X X X X; both allege the same wrongful conduct; both engage events when X X X was the parent company of C; and both will naturally involve similar legal arguments on the legitimacy of R’s measures under international law. Further, in the light of C and X X X’s relationship at the time of the events, there exist common executives who may well be called to testify in both cases.

3.17As a result, R reasons that SS will, exclusively among the arbitrators in both cases, remain privy to the deliberations in the X X X Arbitration and BIT Arbitration involving the same measures, the same conduct, the same events and the same legal arguments. There is therefore a risk of prejudgment and unconscious bias owing to his access to evidence and deliberations not available to his fellow arbitrators, and that he would consequently form externally-influenced views on the BIT Arbitration.

(iii)  Nationality Ground

3.18R relies on the fact that C is a X X X company and SS is a X X X X X national, but contends that the Nationality Ground is based on more than common nationality for the following reasons:

(1)  In terms of X X X X’s interests, it has been the 99% owner of C since late 2022. This gives it a direct financial stake in C’s X X X X X X claims. Moreover, this case is of a highly sensitive political nature raising issues of inter-state, not just investor-state, relations. For example, X X X X X that X X X X X X has adopted against R form part of the factual matrix giving rise to C’s claims and may be relevant to their determination. X X X X therefore has clear interests in these proceedings that transcend the general interest in typical investor-state claims;

(2)  SS has (allegedly) benefited from his years-long employment by the X X X X X X X X X, funded by the X X X X government. He has also been appointed by the X X X X government to its ICSID Panel of Conciliators and then its ICSID Panel of Arbitrators. Given the particular circumstances underlying the BIT Case, there are heightened risks that SS’s X X X nationality and governmental ties will, consciously or not, affect his view of the underlying dispute – or at least appear to a reasonable observer to be so.

4.The applicable legal framework

4.1There is no real dispute on the applicable legal framework.

4.2Section 25 of the AO, which adopts Article 12 of the UNCITRAL Model Law, provides as follows:

“(1) When a person is approached in connection with his possible appointment as an arbitrator, he shall disclose any circumstances likely to give rise to justifiable doubts as to his impartiality or independence. An arbitrator, from the time of his appointment and throughout the arbitral proceedings, shall without delay disclose any such circumstances to the parties unless they have already been informed of them by him.

(2) An arbitrator may be challenged only if circumstances exist that give rise to justifiable doubts as to his impartiality or independence, or if he does not possess qualifications agreed to by the parties. A party may challenge an arbitrator appointed by him, or in whose appointment he has participated, only for reasons of which he becomes aware after the appointment has been made.” (emphasis added)

4.3An arbitrator must not only be independent and impartial, but must appear at all times to be so. The test for apparent bias is “whether an objective fair-minded and informed observer, having considered the relevant facts, would conclude that there was a real possibility that the tribunal was biased”: Jung Science Information Technology Co Ltd v ZTE Corp [2008] 4 HKLRD 776 §§49-50 and Halliburton Co v Chubb Bermuda Insurance Ltd [2020] UKSC 48 §52.

4.4Halliburton describes the attributes of a fair-minded and informed observer to be as follows:

“[52] … The courts have given further guidance on the nature of this judicial construct, the “fair- minded and informed observer” (to whom in this judgment I also refer as “the objective observer”). Thus, in Helow v Secretary of State for the Home Department [2008] UKHL 62; [2008] 1 WLR 2416, Lord Hope (paras 1-3) explained that the epithet “fair-minded” means that the observer does not reach a judgment on any point before acquiring a full understanding of both sides of the argument. The conclusions which the observer reaches must be justified objectively and the “real possibility” test ensures the exercise of a detached judgment. He continued:

‘Then there is the attribute that the observer is ‘informed’. It makes the point that, before she takes a balanced approach to any information she is given, she will take the trouble to inform herself on all matters that are relevant. She is the sort of person who takes the trouble to read the text of an article as well as the headlines. She is able to put whatever she has read or seen into its overall social, political or geographic context. She is fair-minded, so she will appreciate that the context forms an important part of the material which she must consider before passing judgment.'…

[53] Finally, in my consideration of the characteristics of the objective observer, I adopt Kirby J’s neat phrase in Johnson v Johnson (2000) 201 CLR 488, para 53, which members of the House of Lords approved in Helow (above, Lord Hope para 2, Lord Mance para 39) that the fair-minded and informed observer is “neither complacent nor unduly sensitive or suspicious.””

4.5If a challenge against an arbitrator is dismissed by the HKIAC, the challenging party has a right to request the challenge to be decided by the Court of First Instance. Section 26(1) of the AO (which adopts Article 13 of the UNCITRAL Model Law) provides as follows:

“(1) The parties are free to agree on a procedure for challenging an arbitrator, subject to the provisions of paragraph (3) of this article.

(2) Failing such agreement, a party who intends to challenge an arbitrator shall, within fifteen days after becoming aware of the constitution of the arbitral tribunal or after becoming aware of any circumstance referred to in article 12(2), send a written statement of the reasons for the challenge to the arbitral tribunal. Unless the challenged arbitrator withdraws from his office or the other party agrees to the challenge, the arbitral tribunal shall decide on the challenge.

(3) If a challenge under any procedure agreed upon by the parties or under the procedure of paragraph (2) of this article is not successful, the challenging party may request, within thirty days after having received notice of the decision rejecting the challenge, the court or other authority specified in article 6 to decide on the challenge, which decision shall be subject to no appeal; while such a request is pending, the arbitral tribunal, including the challenged arbitrator, may continue the arbitral proceedings and make an award.” (emphasis added)

4.6Mr Chapman accepts that (1) the right to take a failed challenge to the court cannot be contracted out of by the parties and (2) the request under Article 13(3) of the UNCITRAL Model Law is determined de novo and is not in the nature of an appeal.

4.7Whilst the request is decided de novo, it is permissible in principle to accord some weight to the views of the panel appointed under the HKIAC’s Practice Note on Challenge of Arbitrators to provide a recommendation to the Proceedings Committee as to the merits of the challenge: P v D [2024] HKCFI 1132 §4.23. In the present case, the Proceedings Committee appointed a sole panelist (“Panel”) to consider the Challenge and make a recommendation on the merits of the Challenge.

4.8I now proceed to analyze C’s preliminary arguments and R’s grounds in the context of the above legal framework.

5.The Time-Bar Argument

5.1In order for C to succeed on the Time-Bar Argument, it has to establish 2 matters, namely (1) the 15-day time limit set out in the UNCITRAL Rules or the HKIAC Rules is applicable and (2) time should start to run from 4 November 2024, ie when the BOT NOA was received by R’s embassy.

5.2The Procedural Agreement contains the following express provisions:

(1)  Clause 1.1: “The Parties agree to have the [BIT Arbitration] administered by the [HKIAC] with the [HKIAC Rules] being applied to the process and Hong Kong being the seat of the [BIT Arbitration]”;

(2)  Clause 1.2: “The Parties agree that the notice of challenge of [SS] dated 26 November 2024 ("Pending Challenge") shall be decided by the HKIAC (instead of the Arbitration Institute of the Stockholm Chamber of Commerce ("the SCC")”;

(3)  Clause 1.3: “[C] shall notify the HKIAC of this agreement on the Parties' joint behalf and [R] shall submit the Pending Challenge to the HKIAC within three (3) calendar days of the signature of this agreement. For the avoidance of doubt, the date of the notice of challenge shall be deemed to be 26 November 2024 and [R] is to be responsible for payment of any applicable charge/fee associated with the resolution of the Pending Challenge by HKIAC”;

(4)  Clause 1.5: “The Pending Challenge shall be decided by the HKIAC on the basis of the Parties' submissions made as of the date of signing this agreement. Neither party shall request leave to make additional submissions on the Pending Challenge to HKIAC. If HKIAC, on its own initiate, requests one of the Parties to make an additional submission on the Pending Challenge, the other party shall be entitled to make a reply submission”;

(5)  Clause 1.6: “The HKIAC's decision on the Pending Challenge is final, binding, and may not be appealed”;

(6)  Clause 1.7: “The Parties agreeing to the Pending Challenge being decided by the HKIAC is without prejudice to the Parties' positions on the substance of the challenge, including its timeliness”.

5.3In relation to the applicability of the 15-day time limit, Mr Chapman submits that R initially brought the Challenge under the UNCITRAL Rules, or alternatively, Procedural Agreement Clause 1.1 contains the parties’ agreement on the applicability of the HKIAC Rules. The relevant provisions provide as follows:

(1)  Article 11(1) of the UNCITRAL Rules: “A party who intends to challenge an arbitrator shall send notice of his challenge within fifteen days after the appointment of the challenged arbitrator has been notified to the challenging party or within fifteen days after the circumstances mentioned in articles 9 and 10 became known to that party”;

(2)  Article 11.7 of the HKIAC Rules: “A party that intends to challenge an arbitrator shall send notice of its challenge within 15 days after the confirmation or appointment of that arbitrator has been communicated to the challenging party or within 15 days after that party became aware of the circumstances mentioned in Article 11.6.”.

5.4Mr Chapman contends as follows:

(1)  BIT NOA §128 appoints SS and BIT NOA §130 contains a statement that SS has confirmed that he is free of conflicts and will be independent and impartial;

(2)  The BIT NOA was received by R’s embassy on 4 November 2024;

(3)  It is universally accepted that diplomatic missions represent the sending states and that they are state organs for the purpose of attribution of conduct;

(4)  R was therefore notified of the appointment of SS by C on 4 November 2024;

(5)  Since R already knew of the circumstances which gave rise to justifiable doubts as to SS’s impartiality and independence, time therefore started to run from the receipt of the BIT NOA by R’s embassy;

(6)  By Procedural Agreement Clause 1.3, the Challenge was deemed to have been made on 26 November 2024 which was beyond the 15-day time limit.

5.5I note that the Time-Bar Argument was not accepted in the Recommendation. Broadly speaking, the Panel held that time only started to run when the BIT NOA was received by the Ministry of Foreign Affairs on 12 November 2024.

5.6I reject the Time-Bar Argument for the following reasons:

(1)  I do not accept Mr Chapman’s submission that the Challenge was initially brought under the UNCITRAL Rules. Whilst R’s letter dated 26 November 2024 initiating the Challenge did make a reference to the UNCITRAL Rules, R also stated unequivocally at §19 of the letter that there was no agreement on the procedure on how the Challenge was to be determined. Indeed, by a letter dated 5 December 2024, R expressly disagreed with C’s proposal that the BIT Arbitration should be governed by the UNICTRAL Rules;

(2)  Whilst it is true that Procedural Agreement Clause 1.1 records the parties’ agreement on the applicability of the HKIAC Rules, it is far from clear that the parties had intended the HKIAC Rules to apply retrospectively to events which took place in November 2024. In the foregoing regard, whilst Procedural Agreement Clause 1.7 expressly preserves the parties’ positions on the timeliness of the Challenge, I do not read it as having the effect of stating that the HKIAC Rules are to apply retrospectively;

(3)  In any event, I do not accept Mr Chapman’s submissions that time ought to start to run from the receipt of the BIT NOA by R’s embassy in X X X;

(4)  As noted above, the BIT NOA itself provides 5 addresses (4 of which in R) for the purpose of service of the NOA, and insofar as service was to be effected at R’s embassy, such service was addressed to the ambassador. In the present case, as noted in the Recommendation, the BIT NOA was served on the embassy by courier and not via diplomatic channels. I agree with the Panel’s view set out at Recommendation §43, namely that insofar as C relies on the service on R’s embassy, necessary time was required to ensure delivery on the appropriate official in R, and in the circumstances, in the interest of fairness and equity, the appropriate venue and official for service of the BIT NOA ought to have been the Ministry of Foreign Affairs in R and not the embassy;

(5)  In my view, the Panel’s observations stand to reason. After all, Article 11.7 of the HKIAC Rules expressly provides that the 15-day time limit only starts to run after the confirmation or the appointment has been communicated to the challenging party or after that party has become aware of the circumstances that give rise to justifiable doubts as to the arbitrator’s impartiality or independence. In the present case, it seems to me to be factually unrealistic to suggest that communication to the ambassador was sufficient or the ambassador would be aware of the circumstances giving rise to justifiable doubts of SS’s impartiality or independence;

(6)  I further note the observation made at ECT Challenge Decision §§88-91[4], namely that one has to strike a balance between the rival positions adopted by the parties, as a strict application of each may give rise to abuse, such reasoning being consonant with the Panel’s concept of fairness. As observed in the ECT Challenge Decision, R’s position, namely that regardless of when the ECT Notice of Arbitration was delivered to the embassy time only started to run when the relevant government has received the notice, would allow the State to delay arbitration proceedings. Conversely, C’s position may encourage a litigant to file its submissions at a location distant from where the responsible officers are located under the expectation that, by the time the submission reaches them, the relevant time limit may have elapsed;

(7)  In the present case, R has adduced evidence that the BIT NOA was couriered by C’s solicitors directly to the Ministry of Foreign Affairs and the document was received on 12 November 2024. Where service of the BIT NOA at the Ministry of Foreign Affairs was a method adopted by C itself, there is in my view no or no proper justification for C’s reliance only on the service on the embassy.

5.7For the above reasons, even if the HKIAC Rules were to apply retrospectively, time did not start to run until the BIT NOA was received by the Ministry of Foreign Affairs on 12 November 2024. The Challenge, having deemed to have been made on 26 November 2024, was brought within time.

6.The Waiver and Estoppel Argument

6.1C’s overarching submission is that a challenge to an arbitrator based on alleged doubts as to impartiality can be defeated by waiver or estoppel, the mandatory character of an impartial tribunal does not make the right incapable of waiver where the waiver is voluntary, informed and unequivocal: CNG v G & Ors [2025] HKCFI 3598 §§46 and 51.

6.2C says that by Procedural Agreement Clause 1.6[5]:

(1)  R is barred by waiver and promissory estoppel to pursue the present request made under Article 13(3) of the UNICTRAL Rules. It is said that R promised not to pursue court proceedings against the expected HKIAC decision and that that promise was clear and unequivocal. C relied on it by conceding that the legal seat and procedural administration of the BIT Arbitration should be moved to Hong Kong. It is therefore inequitable to allow R to resile from these assurances and pursue the OS before the court;

(2)  Further and/or in the alternative, contractual estoppel also bites, as the parties recorded a common contractual premise that the HKIAC challenge decision would be final, binding and may not be appealed. Having assented to that allocation of risk and finality, R is precluded from denying the agreed state of affairs in order to rerun the same challenge before the court;

(3)  Whilst accepting that the nature of R’s request pursuant to section 26 of the AO is in the nature of a hearing de novo and not an appeal, C contends that the only sensible interpretation of the word “appeal” in Procedural Agreement Clause 1.6 is the request made under Article 13(3) of the UNCITRAL Model Law.

6.3In my view, the Waiver and Estoppel Argument can be disposed of on a relatively straightforward basis. The parties accept that R’s right to resort to the court cannot be excluded by agreement of the parties – see A Guide to the UNCITRAL Model Law on International Commercial Arbitration: Legislative History and Commentary, page 426. C is therefore driven to mount an astute argument that whilst R’s right to resort to the court is preserved despite the Procedural Agreement, the grounds in support of the Challenge are waived or R is estopped from advancing them.

6.4I agree with Mr Manzoni that the above distinction, whilst ingenious, is nevertheless contrived, especially where, as here, Mr Chapman has confirmed that the “source” of the waiver and estoppel is premised exclusively on the Procedural Agreement. Were one to agree with Mr Chapman’s distinction, one would effectively be permitting the Procedural Agreement to oust R’s right to resort to the court.

6.5In any event, I do not believe CNG assists C. In CNG, the Notice of Challenge under Article 11.7 of the HKIAC Rules was served on 10 July 2024. The question was whether the challenging party could rely on any matters which occurred prior to 25 June 2024, outside the 15-day period (§43). Mimmie Chan J held that the challenging party could not, since the challenging party could not stand by in refraining from raising the complaint but continued to take part in the proceedings. The learned Judge was of the view that the case authorities plainly required the challenging party to act promptly, and failure to do so could mean that it waived or was estopped from relying on such matter as an objection later, especially when the challenging party voluntarily continued to participate in the arbitral process (§§46-54). It was in those circumstances that the learned Judge concluded that the challenging party had waived its rights to complain of facts and alleged defects and irregularities occurring before 25 June 2024.

6.6As a matter of legal proposition, CNG is decidedly not a case in support of the proposition that that the right to resort to the court under Article 13(3) of the UNICTRAL Model Law can be “given up” by agreement.

6.7The facts of CNG are also far removed from those of the present case. There is no suggestion that factually R has participated in the furtherance of the BIT Arbitration. To the contrary, it is Mr Chapman’s submission that R has “paralyzed” the underlying arbitral proceedings. In any event, even were the arbitral proceedings progressing, one has to bear in mind that whilst the request made under Article 13(3) of the UNCITRAL Model Law is pending, the arbitral tribunal, including the challenged arbitrator, may continue the arbitral proceedings and Article 11.9 of the HKIAC Rules is of like effect. As such, the continued participation of R in the arbitral proceedings would not have the effect of waiver or estoppel of the Challenge already made.

6.8For the above reasons, even were I to accept Mr Chapman’s argument that the term “appeal” used in Procedural Agreement should be construed as a reference to a request made under Article 13(3) of the UNCITRAL Model Law, I would still reject the Waiver and Estoppel Argument.

7.The Prejudgment Ground

7.1R relies on the following 9 writings published by SS. Chronologically:

(1)  “X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X (“Article No 1”);

(2)  “X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X (“Article No 2”);

(3)  “X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X (“Article No 3”);

(4)  “X X X X X X X X X X X X X X X X X X X X X X X X X X X X (“Article No 4”);

(5)  “X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X (“Article No 5”);

(6)  “X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X (“Article No 6”);

(7)  “X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X (“Article No 7”);

(8)  Article No 8;

(9)  “X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X  (“Article No 9” and collectively “SS Articles”).

7.2At my request, the parties have provided to me their respective tables on those excerpts of the SS Articles on which they rely. I have considered the tables carefully but will only refer to the more obvious examples below.

7.3R’s first proposition is that, in terms of the Maffezini-Plama Divergence, SS has consistently opined that neutrally worded MFN clauses should be uniformly interpreted in favour of importing provisions in other BITs.

7.4For example, in Article No 4, SS stated as follows:

“X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X

X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X ”

7.5In Article No 2, SS stated as follows:

“X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X

X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X”

7.6In Article No 5, SS stated as follows:

“X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X”

7.7In Article No 7, SS stated as follows:

“X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X ”

7.8Mr Manzoni emphasizes that the excerpts in the SS Articles identified by R show that SS’s position is not expressed generally, as reference is specifically made to “X X X X X X X X X X X X X X X X” which covers the BIT.

7.9R’s second proposition is that the SS Articles demonstrate that SS is ideologically committed to arbitrators acting as international lawmakers.

7.10For example, in Article No 4, SS stated as follows:

“X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X”

7.11In Article No 7, SS stated as follows:

“X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X

X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X”

7.12In Article No 6, SS stated as follows:

“X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X”

7.13R.s third and final proposition is that the SS Articles demonstrate that SS understands the importance of arbitrators signaling their predispositions.

7.14In Article No 8, SS stated as follows:

“X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X

X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X”

(i)  The applicable principles

7.15On the issue of how previous opinions expressed by an arbitrator may impact on his independence and impartiality, the parties have referred me to, inter alia, the following cases and materials.

7.16CC Devas (Mauritius) Ltd v India, PCA Case No 2013-09, 30 September 2013 makes the following fundamental observations:

“[58] … The conflict is based on a concern that an arbitrator will not approach an issue impartially, but rather with a desire to conform to his or her own previously expressed view. In this respect, as discussed by the Parties, some challenge decisions and commentators have concluded that knowledge of the law or views expressed about the law are not per se sources of conflict that require removal of an arbitrator; likewise, a prior decision in a common area of law does not automatically support a view that an arbitrator may lack impartiality. Thus, to sustain any challenge brought on such a basis requires more than simply having expressed any prior view; rather, I must find, on the basis of the prior view and any other relevant circumstances, that there is an appearance of pre-judgment of an issue likely to be relevant to the dispute on which the parties have a reasonable expectation of an open mind.” (emphasis added)

7.17In a similar vein, Urbaser SA v The Argentine Republic, ICSID Case No ARB/07/26, 12 August 2010 makes the following observations:

“[45] The Two Members seized with the challenge submitted by Claimants are of the view that the mere showing of an opinion, even if relevant in a particular arbitration, is not sufficient to sustain a challenge for lack of independence or impartiality of an arbitrator. For such a challenge to succeed there must be a showing that such opinion or position is supported by factors related to and supporting a party to the arbitration (or a party closely related to such party), by a direct or indirect interest of the arbitrator in the outcome of the dispute, or by a relationship with any other individual involved, such as a witness or fellow arbitrator.

[46] Indeed if one would prefer to extend such requirement of independence or impartiality beyond this framework, as supported by Claimants, the mere fact of having made known an opinion on an issue relevant in an arbitration would have the effect of allowing a challenge for lack of independence or impartiality. Such a position, however, would have effects reaching far beyond what Claimants seem to sustain, and incompatible with the proper functioning of the arbitral system under the ICSID Convention.

[47] The opinions expressed by Prof. McLachlan are those of an academic. They represent, even when taken together with numerous other opinions expressed by scholars, a small part of all opinions contained in publications relating to arbitrations governed by the ICSID Convention… In the Decision on the proposal for the disqualification of a member of the Arbitral Tribunal rendered in the Suez/Vivendi v. Argentine Republic cases on October 22, 2007, the Two Members stated that the fact that a judge or arbitrator had made a determination of law or a finding of fact in one case does not mean that such judge or arbitrator cannot decide the law and the facts impartially in another case. They further observed that:

‘A finding of an arbitrator’s or a judge’s lack of impartiality requires far stronger evidence than that such arbitrator participated in a unanimous decision with two other arbitrators in a case in which a party in that case is currently a party in a case now being heard by that arbitrator or judge. To hold otherwise would have serious negative consequences for any adjudicatory system.’ (§36)

[48] If Claimants’ view were to prevail and any opinion previously expressed on certain aspects of the ICSID Convention be considered as elements of prejudgment in a particular case because they might become relevant or are merely argued by one party, the consequence would be that no potential arbitrator of an ICSID Tribunal would ever express views on any such matter, whether it may be procedural, jurisdictional, or touching upon the substantive rights deriving from BITs. The wide spreading of ICSID awards through publication and appearance on the Centre’s websitea has greatly contributed to dense exchanges of views throughout the world on matters of international investment law. This is very largely considered as a positive contribution to the development of the law and policies in this segment of the world’s economy. It goes without saying that such a debate would be fruitless if it did not include an exchange of opinions given by those who are actually involved in the ICSID arbitration process, whether they are writing and speaking as scholars, arbitrators, or counsel. Such activity is part of the “system” and well known to all concerned. Therefore, it seems extremely strange to the Two Members to accept Claimants’ position that a view previously expressed on an item relevant in an arbitral proceeding should be qualified as a prejudgment that demonstrates a lack of independence or impartiality.” (emphasis added)

7.18Both CC Devas and Urbaser were referred to in the 2016 Report of the ASIL-ICCA Joint Task Force on Issue Conflicts in Investor-State Arbitration (“2016 Report”). A regards scholarly and professional writing, the 2016 Report observes that:

(1)  With the exception of CC Devas, challenges involving arbitrators’ past expressions of general views on substantive legal issues, either in scholarly or professional writings or in lectures or remarks at professional meetings, have not been accepted (§108);

(2)  The 2016 Report notes at §116 that in an unpublished challenge to Christoph Schreuer in Saipem SpA. v People’s Republic of Bangladesh the unchallenged arbitrators found prior publication of scholarly views unexceptionable. According to Prof. Schreuer’s book, one of the grounds for the challenge was the fact that the arbitrator had expressed opinions in his writings which, in the respondent’s view, showed preconceived positions with regards to some of the central issues of the arbitration. In that case, the unchallenged members of the panel found it is well established by national case law on the removal of arbitrators as well as in the practice of arbitration institutions that an arbitrator’s doctrinal opinions expressed in the abstract without reference to any particular case do not affect that arbitrator’s impartiality and independence, even though the issue on which the opinion is expressed may arise in the arbitration;

(3)  At §§118-121, the 2016 Report explains CC Devas as follows. In that case, the respondent challenged two members of an arbitral panel constituted to hear a large telecommunications-related claim against India. Judge Peter Tomka, then President of the International Court of Justice, the appointing authority under the India-Mauritius bilateral investment treaty, decided the challenge. India challenged both the presiding arbitrator, Hon Marc Lalonde, and the arbitrator appointed by the claimants, Professor Orrego Vicuña, because they had served together on two tribunals (CMS and Sempra) that took a position on a legal issue (“essential security interests”) expected to arise in the current proceedings. The respondent also cited Professor Orrego Vicuña’s participation in a third award addressing the same issue and in a later article defending his views on the issue. The respondent emphasized that all three arbitral decisions were later annulled or annulled in part. After referring to the passage in CC Devas reproduced at §7.2 above, the 2016 Report then refers to CC Devas §64:

“… In my view, being confronted with the same legal concept in this case arising from the same language on which he has already pronounced on the four aforementioned occasions could raise doubts for an objective observer as to Professor Orrego Vicuna's ability to approach the question with an open mind. The later article in particular suggests that, despite having reviewed the analyses of three different annulment committees, his view remained unchanged. Would a reasonable observer believe that the Respondent has a chance to convince him to change his mind on the same legal concept? Professor Orrego Vicuna is certainly entitled to his views, including to his academic freedom. But equally the Respondent is entitled to have its arguments heard and ruled upon by arbitrators with an open mind. Here, the right of the latter has to prevail. For this reason, I agree with the Respondent that Professor Orrego Vicuna should withdraw from this arbitration” (emphasis added)

7.19Consistent with the above, the IBA Guidelines on Conflicts of Interest in International Arbitration (§4.1 thereof) regards that previously expressed legal opinion requires no disclosure as no appearance and no actual conflict of interest can exist under the subjective or the objective standard, as long as the opinion is not focused on the subject case[6].

7.20However, Urbaser also points out a particular feature in Investor-State Arbitrations which is relevant:

[49] The above analysis is not intended to suggest that Claimants’ views are not a matter for debate. It is true, indeed, that each arbitrator's personal opinion is of greater weight in a system like ICSID arbitration than in most other systems of judicial adjudication world-wide. In other judicial systems, decisions are based on precedent that all members of the judicial body have to respect or, at least, observe within a usually small margin for possible overruling, under the control of the appellate body. In such a system, the opinion of an individual judge counts for little to the extent that previous precedents have to be followed. This is not how ICSID arbitration operates. Despite many statements made in ICSID awards affirming the necessity or the duty to achieve consistency through ICSID case law, the principle remains that each Tribunal is sovereign in its decision making. This autonomy also applies to decisions rendered by Annulment Committees, which do not have precedential value and are not in practice considered as having such value. This necessarily implies that weight is given to the opinion of each member of an ICSID Tribunal. However, this is not without limits. The requirement of independent and impartial judgment means that an arbitrator’s previously adopted opinion, whether published or not, shall not be of such force as to prevent the arbitrator from taking full account of the facts, circumstances, and arguments presented by the parties in the particular case.” (emphasis added)

7.21The feature identified above is also noted in the 2016 Report:

“[177] …What sets potential prejudgment in investor-State arbitration apart from potential prejudgment in national courts or other international tribunals is the fact that, in investor-State cases, the majority of the tribunal is typically nominated by the parties. This creates the perception that the selection of arbitrators is, in fact, a means of rigging the game unfairly in the nominating party’s favor… ”

(ii)  Analysis

7.22As Mr Manzoni emphasizes, the key is whether the SS Articles demonstrate that SS will not hear the arguments to be made with an open mind (or there is an appearance that he will not). In my view, the Prejudgment Ground does not satisfy the requisite test for the removal of SS as an arbitrator in the BIT Arbitration.

7.23First, the principles set out above all point to a conclusion that abstract doctrinal commentary is insufficient to give rise to doubts as to an arbitrator’s independence and impartiality.

7.24Secondly, having considered the excerpts relied on by the parties, I agree with the Panel’s view that SS Articles relied upon by R are general scholarly writings on MFN issues, not opinions about the present case, the BIT in question, or the parties to these proceedings. I agree with the Panel that the SS Articles do not demonstrate that SS would prejudge matters in the BIT Arbitration, and to the contrary, the SS Articles in fact emphasize the duty of arbitrators to approach issues with an open mind and on a treaty-by-treaty basis.

7.25Thirdly, and related to the second point above, it seems to me that it is relevant to consider the timing of the publications of the articles. As pointed out by Mr Chapman, C had in fact unsuccessfully challenged the arbitrator, X X X X X X X X X X, appointed by R in the ECT Arbitration (X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X). In that case, C challenged X X X X X X on the basis that, in an earlier case, she had already concluded, in a dissenting opinion, that the ECT did not apply provisionally to X X X , ie the very same jurisdictional question arising in the ECT Arbitration. The appointing authority nonetheless rejected the challenge, in part premised on the time elapsed since the earlier decision:

“[102] The views that X X X X expressed in her dissenting opinion in Yukos are close to 10 years old and—while the Claimant has taken issue with the length of her dissenting opinion - no claim has been made that the language used therein was obstinate or disparaging. The differences between the cases and the passage of time since her prior opinion was issued provide sufficient space for a third party to conclude that - however relevant to this case the dissenting opinion may be - X X X X would not be unable to address this case with an open mind. Thus, these circumstances would not lead a reasonable, informed, and neutral observer to find that there are justifiable doubts regarding X X X’s impartiality.”

7.26As such, focusing on the more recent Article Nos 8 and 9 (and even then they were written some time ago in 2015 and 2016), it is plain from the excerpts relied on by C that SS took the following views:

(1)  The Maffezini-Plama Divergence is “X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X”;

(2)  Attention must be paid to the wording of the MFN clause in question and the correct approach is to interpret the clause “X X X X”;

(3)  Consensus has emerged that there are no interpretive presumptions, either in favour of States or investors, when determining whether an MFN clause applies to more favourable consensus to dispute settlement elsewhere. Various tribunals have clarified that this was a matter of treaty interpretation and no different from interpreting any other treaty provision, whether substantive or procedural;

(4)  The interpretation of MFN clause has to start with a treaty by treaty approach that is attentive to the text, context, and object and purpose of the clause in question.

7.27The above excerpts plainly militate against R’s suggestion that SS will not keep an open mind or there is an appearance that he will not do so.

7.28Fourthly, as stated earlier, CC Devas is an exception, and the facts of present case are entirely different. There is no or no comparable evidence to show that SS holds a like degree of obstinacy demonstrated by Professor Orrego Vicuña.

7.29Fifthly, I also agree with Mr Chapman that the high point of R’s case rests on the excerpts found in Article No 8 set out at §7.14 above. However, read in context, it is obvious that the passage describes the state of the wider scholarly debate, not SS’s own adjudicative posture in any given case. Indeed, in his email dated 14 May 2025 to the HKIAC, SS confirmed that he would “approach any issue that divides the parties in this arbitration with an open mind and read and listen to their arguments and submissions and take them into account in forming an opinion on the relevant matters independently of whether [he] may have written on them or not and whether [he has] otherwise been exposed to them in another capacity.”

7.30Sixthly, I also find force in Mr Chapman’s submission that the fair-minded observer would take note of R's own admission in its Notice of Challenge that it does not question SS’s general fitness or competence to act as an arbitrator.

7.31For the above reasons, I reject the Prejudgment Ground. In my view, a fair-minded and informed observer, having been apprised of the above matters, would not conclude that SS has prejudged the Maffezini-Plama Divergence as it arises in the BIT Arbitration, or that there is a perception of SS having done so.

8.The Multiple Appointments Ground

8.1As SS has already been removed as an arbitrator in the ECT Arbitration, this leaves R’s complaint based on SS’s appointment in the X X X X X X Arbitration.

8.2The Panel concluded that the alleged concern arising from SS’s parallel appointment in the ECT Arbitration became moot once he was removed in those proceedings. On the X X X Arbitration, the Panel was of the view that R failed to show the additional significant overlap of facts and parties required by the authorities to potentially create an issue of impartiality. The Panel held the record insufficient to justify removal on that basis. In any event, the Panel also expressly endorsed the orthodox position that repeat appointments by the same party do not without more evidence a lack of independence or impartiality.

8.3Mr Manzoni relies on Caratube International Oil Company LLP v Kazakhstan, ICSID Case No. ARB/13/13, 20 March 2014, Liberty Seguros v Venezuela, ICSID Case No. ARB(AF)/20/3, 1 July 2021, Anaklia Development Corporation v Georgia, ICC Case No. 25542 HBH, 25 February 2021 and Deutsche Lufthansa AG v Venezuela, PCA Case No 2022-03, 10 October 2022).

8.4In each of the above cases, the challenged arbitrator was removed since it had been demonstrated or it was not disputed that the challenged arbitrator was involved in concurrent cases which were similar, share common matters of fact and law, or closely connected. The reasons were variously stated as follows.

8.5In Caratube:

“[75] The Unchallenged Arbitrators agree with the Claimants that the similarity in cases, in particular in the facts underlying the Ruby Roz case and the present arbitration, is an important consideration in the assessment of Mr. Boesch’s perceived impartiality in the present arbitration. As was observed in Tidewater Inc. et al. v. The Bolivarian Republic of Venezuela and EnCana Corporation v. Republic of Ecuador, a problem can arise where an arbitrator has obtained documents or information in one arbitration that are relevant to the dispute to be determined in another arbitration. In this situation, the arbitrator ‘cannot reasonably be asked to maintain a ‘Chinese wall’ in his own mind: his understanding of the situation may well be affected by information acquired in the other arbitration…

[90] …a reasonable and informed third party would find it highly likely that, due to his serving as arbitrator in the Ruby Roz case and his exposure to the facts and legal arguments in that case, Mr. Boesch’s objectivity and open-mindedness with regard to the facts and issues to be decided in the present arbitration are tainted. In other words, a reasonable and informed third party would find it highly likely that Mr. Boesch would prejudge legal issues in the present arbitration based on the facts underlying the Ruby Roz case.”(emphasis added)

8.6In Anaklia:

“[26] The Court considered that it is difficult to speculate on the exact time and sequence of the decisions to be made in both arbitrations and that challenges must be decided on the basis of the facts as they stand when the Court decides. It suffices for a risk of prejudgment to exist that similar issues of fact or law exist in different proceedings that are pending at the same time involving the same arbitrators. Although the Court has no reasons to doubt that Mr. Sachs would fulfil his duties with fairness and integrity, the risk of unconscious biases resulting from the involvement in two overlapping proceedings cannot be discarded.

[27] With respect to the asymmetry of information, although Claimant and Mr. Meijer are represented by the same legal counsel in both cases, the Court considered that Mr. Sachs may still have access to information that will not be available to his fellow arbitrators in the ICC proceedings, who will not participate to the ICSID Case, including evidence submitted in the ICSID Case that may not be produced in the ICC case, as well as internal discussions and deliberations within the ICSID arbitral tribunal. It may moreover not be excluded that legal representation in either case could change during the course of the proceedings.” (emphasis added)

8.7I have already set out R’s factual case at §§3.16 and 3.17 above. R relies on both the risk of bias arising from the common issues and arguments raised in the BIT Arbitration and the X X X Arbitration, and also the consequential problem created by the asymmetry of information. Whilst recognizing that both sets of arbitral proceedings are at an early stage, Mr Manzoni says that the court must take a view on the above risks which are necessarily prospective and forward looking, which he complains that the Panel did not do.

8.8Mr Chapman disputes both propositions. First, he says the X X X X Arbitration is not related to the BIT Arbitration as it involves a different claimant (entirely unconnected to C), different treaties, a different investment and different counsel. In any event, he submits that on the authorities, parallel appointments, even where the arbitrations concern a similar subject matter, do not on their own give rise to justifiable doubts. Secondly, he maintains that the hypothetical scenarios set out at §§3.16 and 3.17 above are unavailing.

8.9Mr Chapman relies on Electrabel S.A. v. The Republic of Hungary, ICSID Case No. ARB/07/19, 25 February 2008. In Electrabel, the challenged arbitrator was appointed by Hungary as arbitrator in two sets of proceedings. As described at §39, Hungary acknowledged that both cases have been brought by electricity generators with long-term Power Purchase Agreements (PPAs) with a Hungarian state-owned company, and are based on alleged violations of the ECT. The other set of proceedings was brought by AES Summit Generation Limited and AES-Tisza Eromu Kft (“AES arbitration”), entities unrelated to Electrabel.

8.10Electrabel §37 summarizes the factors underlying the challenge:

“[37] The Claimant, in its last submissions, helpfully listed the several factors comprising its complaint as to Professor Stern’s “manifest “ incapability of exercising independent judgment in these arbitration proceedings:

(a) Professor Stern has been appointed by the same party, Hungary, in the AES case;

(b) Hungary is represented by the same law firm, Arnold & Porter, in the AES case;

(c) Both arbitrations arise out similar factual circumstances relating to the generation of electricity in Hungary;

(d) Both arbitrations arise out of similar long-term Power Purchase Agreements (PPAs);

(e) Both arbitrations concern, among other disputes, the same governmental decree;

(f) Both arbitrations relate to the same treaty, the ECT; and

(g) Both arbitrations were registered on the same day, 13th August 2007, and the two proceedings will likely run more or less in parallel.”

8.11The reasons for rejecting the challenge in that case were as follows:

“[38] If we were to consider separately these individual factors (a) to (g) , there would in our view be nothing left to the Claimant’s complaint. Rightly, the Claimant almost concedes as much… However, that is not the way the Claimant advances its proposal: it seeks to put together these individual factors and then complain of their “combination.”

[39] On the established facts of this case, we consider that the combination of factors (a), (b), (d), (e), (f) and (g) do not impugn the independent judgment to be exercised by Professor Stern. Nor do we consider, in this case, that it can make any difference when the Claimant packages all these factors together. In our view, the Claimant’s own methodology brings about its own demise: 0 remains 0 and not 7. Two or more factors which do not satisfy the test required under Article 57 cannot, by mere “combination,” meet that test.

[40] We recognise that factor (c) could potentially fall into a different category . However, by itself at this very early stage of these proceedings, it is not possible for us to know enough about any relevant issue in these proceedings, still less any such issue overlapping between this arbitration and the AES arbitration. On the materials we have seen so far, we do not consider that the Claimant has provided sufficient proof of factor (c) as a relevant matter under Article 57, whether assessed separately or in combination with any other factor(s). In our view, it does not, at present, give rise to any reasonable or clear doubt or real risk in regard to the exercise of independent judgment by Professor Stern in this case.

[41] Moreover, the Claimant’s combination of factors (c)-(f) not only assumes the end-result desired by the Claimant but it proves far too much. Investment and even commercial arbitration would become unworkable if an arbitrator were automatically disqualified on the ground only that he or she was exposed to similar legal or factual issues in concurrent or consecutive arbitrations. For example, every ICSID arbitration relates to the same ICSID Convention, just as many treaty arbitrations relate to the same Vienna Convention. As for governmental decrees and contractual wording, it is commonplace for arbitrators to review the same legislation or standard form of contract, … We do not consider that Article 57 can now be interpreted, after more than forty years, effectively to outlaw widespread practices so long accepted by users and practitioners generally, particularly when such practices have helped to establish a growing body of specialist and experienced international arbitrators, so long desired by users.”

8.12Importantly, in relation to factor (c), it was observed as follows:

“[44] We do not, however, exclude the theoretical possibility of factor (c) becoming a procedural problem in the future: one or more factual issues might possibly overlap between the two arbitrations; and, if it did, that overlap might possibly embarrass Professor Stern and the other two members of the Tribunal; and it might possibly also cause difficulties for the Claimant. Investment arbitration requires procedural vigilance at all times for many reasons; and these theoretical possibilities may provide a further reason for vigilance in this case. However, we are all now alerted to these possibilities; the Claimant is also represented by experienced arbitration practitioners; there can now be no material waiver or acquiescence asserted against the Claimant; and there is no present reason to think that any procedural problem cannot be addressed at the time to the mutual satisfaction of both Parties and the Tribunal.

[45] In this regard, it is worthwhile recalling Professor Stern’s statement from her letter cited at the beginning of this document, together with the concluding terms of her signed declaration: see paragraphs (6) and (12) above. We are therefore confident that if there were ever a problem, we would learn of it promptly from Professor Stern herself.

[46] Decision: For these reasons, we decide that the Claimant’s proposal to disqualify Professor Stern is not well-founded under Article 58 of the ICSID Convention and Rule 9(4) of the ICSID Arbitration Rules.”

8.13Mr Chapman has carried out a forensic exercise in support of the observations made at Electrabel §41, namely that it is commonplace in investor-States disputes for an arbitrator to be appointed in parallel arbitrations. By way of example, Gabrielle Kaufmann-Kohler and Brigitte Stern were appointed in 7 and 6 arbitrations respectively against Argentina. Guido Santiago Tawil and Zachary Douglas were appointed in 4 and 3 arbitrations respectively against Spain. R itself appointed the same arbitrator, Judge Schwebel, across three parallel arbitrations brought by former shareholders of the Yukos Oil Company.

8.14I find the approach adopted in Electrabel sensible and its reasoning compelling. I accept D’s evidence that, at its highest, R’s case is that SS may have to consider similar governmental measures (eg X X X X ) in the BIT Arbitration and the X X X Arbitration. Whether factor (c) identified in Electrabel eventually presents a problem cannot be determined at this stage. I agree with the Panel’s following views:

“[SS] stated that based on the Notice of Challenge, there seems to be only limited overlap between the BIT/ECT arbitrations and the X X arbitration which only concerns state conduct that is in the public domain, such as presidential decrees… [SS] expressed the view that he was "at present' (original emphasis) unable to see what the additional significant overlap of facts that are specific to the merit and the parties involved and how his impartiality and independence could be affected on that basis…

The Panel needs to be satisfied that, based on information before the Panel, circumstances currently exist that give rise to justifiable doubts about the arbitrator's independence or impartiality in order to make a recommendation that an arbitrator be removed… I am unable to conclude whether or not the arbitrations consist of sufficient overlaps in accordance with the reasoning and test in paragraphs 75-88 of Caratube II. I therefore come to the conclusion that the present information regarding the X X  arbitration is insufficient to result in a recommendation on the removal of [SS] from the BIT arbitration.”

8.15For the above reasons, I reject the Multiple Appointments Ground. I acknowledge that the matters raised by R, like factor (c) in Electrabel, is a theoretical possibility. But, at this stage, the fair-minded and informed observer would conclude that such theoretical possibility is insufficient to warrant removal of SS, given (1) the considerations set out at Electrabel §41, (2) the possibility that the issue may be revisited in the future should circumstances so justify and (3) the procedural vigilance which is or ought to be in place. In relation to the last factor, as noted by the Panel, SS is aware that his view that there is only limited overlap between the BIT Arbitration and the X X X Arbitration is a provisional view formed “at present”, and I have no doubt that SS will keep the matters under review and make appropriate disclosure at the appropriate juncture. In any event, R, being a party in both the BIT Arbitration and the X X X Arbitration, is likewise in a position to raise any concerns at the appropriate juncture should circumstances so warrant.

9.The Nationality Ground

9.1R’s underlying premises for the Nationality Ground are set out at §3.18. I am in broad agreement with the Panel that R’s arguments do not cast any doubt on the independence and impartiality of SS. In summary:

(1)  The applicable rules do not prohibit the appointment of SS based on his nationality. Article 11.2 provides that as a general rule, where the parties to an arbitration are of different nationalities, a sole or presiding arbitrator shall not have the same nationality as any party unless specifically agreed otherwise by all parties. In the present case, I am told that the presiding arbitrator appointed is Lebanese;

(2)  The X X X X X X X X X X is a research institute for X X X X X X X X X X X X X X X X X X X X X X X X and the nature of his appointment which is limited to an honorary non-remunerated position and which he carries out with no benefit in terms of research funding. Though non-receipt of remuneration may not be the only factor justifying the independence and impartiality of an arbitrator in this circumstance, no material has been placed before me that could lead to doubts being cast on the independence and impartiality of SS on the basis of his appointment with X X X X X X X X as an employee from September 2009 until December 2014 and since then, as a X X X X X X X X X X X;

(3)  The assertion that SS was at one time appointed by X X X X X to the ICSID Panel cannot, without more, create justifiable doubts under the objective test;

(4)  X X X X 's actions with respect to X X X X X X X, its implementation X X X X as well as its membership of the X X and the X X X X X X X X X X X X X X X  are not reasons to cast doubt on SS’s impartiality and independence;

(5)  Neither does the fact that X X X X  may have an interest in the outcome of the dispute have the effect of casting doubt on SS’s impartiality and independence.

9.2For the above reasons, I reject the Nationality Ground. In my view, a fair-minded and informed observer would not conclude that the Nationality Ground gives rise to any justifiable doubts on SS’s impartiality and independence.

9.3For avoidance of doubt, I have also considered Mr Manzoni’s submission that the grounds should be assessed cumulatively. Mr Manzoni submits that even if the court considers that the 3 grounds individually do not cross the threshold required for disqualification, their aggregate effect may give rise to justifiable doubts: Merck Sharp & Dohme (IA) Corporation v Ecuador, PCA Case No. AA442, 8 August 2012 §94.

9.4In the present case, Mr Manzoni submits that the 3 grounds collectively amount to a “pattern of circumstances” giving rise to doubts as to the impartiality and independence of SS.

9.5I do not agree with Mr Manzoni. All of the cases relied on by R are concerned with a problematic issue and the failure by the challenged arbitrator to disclose that issue. Mr Manzoni is therefore driven to rely on the new allegation SS failed to disclose the SS Articles. I do not believe R can now rely on this new ground in the Challenge, and in any event, as noted above, there is no requirement to disclose previously expressed legal opinion.

9.6I have considered the grounds cumulatively. In my view, the merits of each of the grounds fall so far below the merit threshold that the amalgamation of them does not result in a successful challenge.

10.Conclusion and costs (including C’s application to vary the costs order nisi in my decision dated 30 January 2026)

10.1For the above reasons, the OS is dismissed. I also make a costs order nisi that R is to pay to C the costs of the OS (including any costs reserved) on an indemnity basis to be taxed if not agreed.

10.2I refer to my decision dated 30 January 2026 (“Decision”). At 8.2 thereof, I made a costs order nisi that the costs of the Amendment Summons and the Security Summons be paid by C to R to be summarily assessed (“Costs Order Nisi”). As stated in the Decision, one of the arguments mounted by R was that it was entitled to sovereign immunity from jurisdiction and execution of the Security Summons. I was able to dispose of the Security Summons without a determination of the sovereign immunity issue. Following the Decision, C was concerned that should it prevail in the OS, it might be faced with a situation that, on the one hand, it would not be able to recover costs from R should R continue to assert sovereign immunity, but on the other hand, was still required to pay R’s costs under the Costs Order Nisi. It therefore issued a summons dated 13 February 2026 to vary the Costs Order Nisi (“Variation Summons”). The position taken by C is that the Costs Order Nisi should be varied to costs in the cause or costs reserved.

10.3Whilst R points out that the state immunity issue was raised only in respect of the Security Summons, there is no concrete confirmation from R whether it will raise the issue again in respect of the costs of the OS. In these circumstances, it seems to me that C’s concerns are real.

10.4As indicated at the hearing, I will simply make a costs order nisi in respect of the OS. In the event that R does decide to raise the sovereign immunity argument, that will be done in the context of an application for variation.

10.5In these circumstances, it seems to be that it is only fair that the Variation Summons be determined after R has made clear its position. This is because, if R does not seek a variation of the costs order nisi made in respect of the OS, on a practical level, C may apply a set off now that the costs of the OS are awarded in its favour. On the other hand, if R does raise the sovereign immunity issue, it is a factor which is relevant as to whether I should vary the Costs Order Nisi. Provisionally, it appears to me that it is unattractive for R to seek an immunity from a costs liability when it failed in proceedings started by it.

10.6I therefore reserve the determination of the Variation Summons until the costs order made in respect of the OS has become absolute.

Mr Charles MANZONI, SC leading Mr Elson TONG instructed by Messrs BF & Co, for the Plaintiff

Mr Simon CHAPMAN and Mr Antony CROCKETT of Messrs Herbert Smith Freehills Kramer, for the Defendant