Public International Law and Investment Treaty Disputes
Allen & Overy’s specialist Public International Law team acts for corporations, financial institutions, international organisations, governments and States in all aspects of contentious and non-contentious public international law matters, including investment disputes.
Our market leading practice combines expertise in issues such as title to natural resources, state responsibility and succession, boundary disputes, investment treaty arbitration, trade law and sanctions.
A&O’s advisory work spans the full range of public international law issues, including:
- drafting and negotiation of international treaties and conventions
- investment protection measures
- international sanctions regimes
- privileges of international organisations and state immunity
- recognition of states and state succession
- human rights
- trade law
On the contentious side, we have a pre-eminent investment treaty arbitration practice acting for investors and sovereign States. We have advised on more than 70 investment treaty disputes and a number of ICSID annulment proceedings, and are one of only a handful of law firms to have experience of WTO disputes.
We advise on State-to-State disputes arising under public international law and team members have acted as counsel before international courts and special tribunals, and have also advised States on out-of-court strategies for dispute resolution.
Our experience includes advising:
- A State on its negotiation with the European Union in relation to a comprehensive free trade agreement.
- A Middle Eastern State on the potential reform of its investment treaties.
- The investment arm of a Middle Eastern State in relation to a draft bilateral investment treaty being negotiated with a South American State, and on how best to structure new investment acquisitions in that State.
- Over 30 different international investors, in 12 separate ECT claims (all claims bar one brought at ICSID) against the Kingdom of Spain. The claims relate to investments made in the Spanish renewable energy sector, and retrospective changes by Spain to the regulatory framework. These cases include the first-ever collective, or aggregated, claim brought under the ECT. We have so far achieved significant damages awards for our clients in six of these arbitrations, with others still pending.
- The Islamic Republic of Pakistan in two related claims, brought under the UNCITRAL Rules, arising from alleged interference in gas import operations at a port terminal. The Tribunal dismissed the nearly USD600m claims in their entirety and ordered the claimants to pay nearly 90% of Pakistan’s costs. We successfully defeated challenges to the Award, made by the claimants, in the English courts.
Awards and achievements
- Tier One, Public International Law, Legal 500 UK 2022
- Band 1, Dispute Resolution, Global: Multi-Jurisdictional, Chambers Global 2022
- International Arbitration Firm of the Year, Benchmark Litigation Asia-Pacific Awards 2020
- Leading firm (top tier) ranking in the “Leaders League” table for International Arbitration (Spain) 2022
Strong track record in representing sovereign states and corporates in high-value investment treaty disputes. Considerable experience carrying out its own advocacy before courts and tribunals. Also adept at handling a number of other public international law matters, such as ECT claims, WTO cases, sovereign immunity concerns, and international treaty drafting and negotiation.
Chambers UK 2022, Public International Law
The team has incredible breadth and expertise in public international law. I have always been impressed by the quality of their work and their excellent reputation is well deserved.
Legal 500 UK 2022, Public International Law
Highly regarded for its stellar track record in representing sovereign states and corporates in high-value investment treaty disputes.
Chambers UK 2022, International Arbitration
Activity in high-profile ECT cases showcases its capacity to coordinate complex investor-state mandates between its breadth of offices.
Chambers Europe 2022, International Arbitration
Highly regarded for its expertise in investment treaty arbitrations. Experienced in arbitrations acting both for and against sovereign states and government bodies.
Chambers Asia-Pacific 2020, International Arbitration, China
Has a great deal of experience acting for both claimants and respondents in investment treaty disputes…Wins further recognition for its thriving sanctions practice and expert advice on sovereign immunity, Energy Charter Treaty claims, WTO matters and EU law.
Chambers Global 2020, Public International Law
News and insights
Publications: 21 March 2022
International law considerations for foreign investors with business interests in Russia As a result of international sanctions and reputational concerns, many foreign investors with interests in…
Publications: 17 March 2022
Updated 1 April 2022: Sanctions remain at the top of the agenda following Russia's invasion of Ukraine.
Publications: 15 February 2022
Allen & Overy’s International Arbitration Group invites you to join a discussion of the reforms of the Arbitration Act 1996 being considered by the Law Commission (and some reforms that are not).
Publications: 10 November 2021
In General Dynamics v Libya  UKSC 22, the UK Supreme Court confirmed that diplomatic service of court documents on a State’s Ministry of Foreign Affairs is mandatory when enforcing an arbitral…