When a foreign investor and a sovereign state end up on opposite sides of a dispute, the stakes rarely stay small. A licence is revoked, a concession is cancelled, a tax measure is applied retroactively, or a regulator changes the rules mid-project and suddenly a commercial relationship becomes a question of international law. These are the cases that fall within the world of investor-state arbitration, most often brought under the ICSID Convention or the UNCITRAL Rules, and they demand a different calibre of decision-maker than an ordinary commercial dispute.
Under the ICSID framework, unless the parties agree otherwise, a tribunal is typically constituted with three members: one nominated by each side, and a presiding arbitrator agreed between them or appointed by the Centre. Getting that appointment right, whether as a party-nominated co-arbitrator, presiding arbitrator or member of an arbitral tribunal more generally, is often the single most consequential procedural decision either side makes. The person in that seat weighs sovereign conduct against treaty standards such as fair and equitable treatment, expropriation and full protection and security, often under intense political and public scrutiny.
Why sovereign disputes call for a different kind of arbitrator
A commercial arbitrator resolves a contract dispute between two private parties on roughly equal footing. A sovereign dispute arbitrator is to do something harder: sit in judgment on the conduct of a state, often in a matter with foreign policy implications, while remaining scrupulously independent of both the investor and the government involved. That calls for fluency in public international law and treaty interpretation, familiarity with sovereign immunity principles, and the institutional credibility to ensure an award is respected by both a private claimant and a national government.
Parties appointing a co-arbitrator in this space typically look for a specific combination: direct case experience in ICSID or UNCITRAL proceedings, ideally on both the investor and the state side; a dual-qualified or multi-jurisdictional background signalling genuine neutrality rather than allegiance to one legal tradition; and enough institutional grounding through bodies such as ICSID itself or the Chartered Institute of Arbitrators to make the appointment defensible if it is ever challenged.
The sectors where sovereign disputes actually arise
Investor-state claims rarely emerge in the abstract; they cluster around the sectors where governments retain the heaviest regulatory hand. Energy is the clearest example: licence revocations, changing renewable tariffs, and regulatory intervention in oil and gas concessions have generated some of the largest ICSID caseloads of the past decade, which is why so many of these disputes are ultimately routed to an energy dispute arbitrator with direct experience of production-sharing contracts and energy treaty claims.
Infrastructure is the other recurring flashpoint. Large-scale roads, ports, power plants and transport concessions depend on long-term state cooperation, and a change of government, a cancelled permit or a renegotiated concession can just as easily give rise to a treaty claim as a construction dispute. That overlap is why an infrastructure dispute arbitrator who also understands the investment-protection layer above the commercial contract is increasingly the preferred appointment for state-linked infrastructure claims.
What parties should look for before nominating an arbitrator?
Before naming a candidate, sophisticated parties tend to ask a short but demanding set of questions. Has this individual actually sat as an arbitrator or acted as counsel in ICSID or UNCITRAL investor-state proceedings, rather than only in commercial arbitration? Do they hold bar admissions or qualifications across more than one jurisdiction, reducing the risk that either side perceives a home-field advantage? Have they worked within an institution, the World Bank’s ICSID, a major international arbitration practice, or a recognised professional body in a way that demonstrates disciplined, transparent decision-making under scrutiny? And can they show sector-specific fluency in the industry at the heart of the dispute, whether that is energy licensing, infrastructure concessions, mining royalties or banking regulation?
None of this diminishes procedural discipline. IBA Guidelines on Conflicts of Interest, disclosure obligations and the tight timelines governing tribunal constitution under the ICSID Arbitration Rules all still apply. But in sovereign disputes, procedural competence is the baseline, not the differentiator. What separates a workable appointment from an outstanding one is substantive command of treaty law layered on top of real sector knowledge the kind that lets an arbitrator ask the right question about a concession agreement without needing a tutorial from counsel first.
Making the appointment
For counsel or an institution weighing a nomination, the practical starting point is a candidate’s track record under the specific treaty framework in question ICSID, UNCITRAL or a regional mechanism combined with hands-on exposure to the sector generating the claim. Energy licence disputes call for someone who has actually worked energy sector arbitrations; infrastructure concession disputes call for someone who understands both FIDIC-style contracts and the treaty protections sitting above them. Getting that match right, rather than defaulting to a generalist, is what gives an award the durability to survive annulment and enforcement challenges across jurisdictions.
Sovereign and investment treaty disputes will only grow more frequent as governments intervene further in energy transition, resource nationalism, and large infrastructure programmes. Parties navigating that landscape are best served by appointing an arbitrator whose credentials match the treaty framework, the sector, and the sovereign counterparty.
Propose Harshavardhan Sancheti as accepting appointment as sole arbitrator via party nomination, institutional appointment (ICC, LCIA, SIAC) or ad hoc proceedings.
