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Sub practice
Sub practice

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

  1. Tier One, Public International Law, Legal 500 UK 2019
  2. Band 1, Dispute Resolution, Global-wide, Chambers Global 2019
  3. International Arbitration Firm of the Year, Benchmark Litigation Asia-Pacific Awards 2019
  4. Best Arbitration Team of the Year in Spain and Portugal, 2019 

Recognition

News & insights

Coding on an LCD computer screen

Publications: 21 JUNE 2021

A guide to Hong Kong’s cyber security laws and practices

The past decade has seen a huge increase in the incidents of cyber crime in Hong Kong. This has been exacerbated by the global pandemic, which has forced criminals online, with the number of cases in…

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Hong Kong's Securities and Futures Commission (SFC) Enforcement Actions Tracker

Publications: 15 JUNE 2021

Hong Kong’s Securities and Futures Commission (SFC) Enforcement Actions Trends and Tracker

The SFC's latest annual and quarterly reports highlight the SFC's regulatory work since April 2019 and illustrate some key trends in its enforcement agenda.

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A laptop computer, cup and pen and pad sitting of a small desk

Publications: 08 JUNE 2021

Can arbitrators rely on their own internet research in an award?

The risk of annulment is different for arbitrations seated in Germany, England and France. Just ask Google. Whatever the question, our first port of call is to check the internet. But are arbitrators…

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building

News: 03 JUNE 2021

Allen & Overy publishes empirical study on Costs, Damages and Duration in Investor-State Arbitration

We are delighted to announce the publication of the latest iteration of the study on “Costs, Damages and Duration in Investor-State Arbitration” authored by Allen & Overy partner Matthew Hodgson and…

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