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Investment Treaty Arbitration

Allen & Overy is recognised as one of the leading investment treaty practices in the world and we are at the forefront of resolving disputes that arise under bilateral and multilateral investment treaties.

We have represented our clients in more than 50 investment treaty claims and have extensive experience of handling arbitration proceedings under the ICSID Convention and the UNCITRAL Arbitration Rules. We regularly represent both sovereign States and claimant investors in these complex disputes.

In addition, we advise states in relation to the negotiation of, and accession to, investment treaties and other public international law instruments, such as free trade agreements. We also advise clients in relation to the structuring, and restructuring, of their overseas investments to secure investment treaty protection.

Ours is a truly global practice, with leading investment treaty practitioners in a number of locations around the world, including London, Paris, Hong Kong, Dubai and Singapore.

We are recognised as being innovators in this field and as having particular expertise in relation to disputes arising under the Energy Charter Treaty (ECT). Our experience includes bringing the very first arbitration under the ECT, as well as the first collective claim under the ECT.

Recent examples of our work

Representative examples of our recent work include acting for:

  • Deutsche Bank in its claim against Sri Lanka, under the Germany-Sri Lanka bilateral investment treaty, for interfering with obligations in an oil hedging agreement between the bank and a state-owned oil company. Deutsche Bank was awarded its claim in full, plus interest and its full legal costs, totalling around USD78 million. This is the first case to find a complex financial product to be a protected “investment” and is one of only three investment cases (out of more than 200 for which data are available) where the investor recovered 100% of its claim. 
  • More than 25 international investors in seven separate investment treaty claims brought under the Energy Charter Treaty against the Kingdom of Spain. The claims relate to multiple investments in the solar power and wind sectors, made on the basis of a regime designed to encourage investments in the Spanish renewable energy sector. Spain subsequently changed its legislative and regulatory measures, with retrospective effect. The claims include the first ever collective, or aggregated, claim brought under the ECT (PV Investors v Spain). 
  • The Islamic Republic of Pakistan in:
    • two related claims, brought under the UNCITRAL Rules, arising from alleged interference in gas import operations at a terminal at the country’s second-biggest port. After ten days of hearings at which we did all the advocacy for our client, the Tribunal dismissed the nearly USD600m claims in their entirety and ordered the claimants to pay nearly 90% of Pakistan’s costs.
    • a third ongoing investment treaty arbitration at ICSID, arising from the arrest by Pakistan of certain ships belonging to Turkish power-ship company Karkey Karadeniz, which values its claim at in excess of USD2 billion; and
    • a fourth claim, brought by Australian mining company, Tethyan Copper Company, in relation to a mining concession in the Balochistan Province of Pakistan. This multi-billion dollar claim is also brought at ICSID.
  • British Caribbean Bank Limited (BCB) and Dunkeld International Investment Limited in investment treaty claims against Belize, arising out of the Government of Belize’s nationalisation programme of the main telecommunications provider in Belize, Belize Telemedia. In 2014, an UNCITRAL Tribunal rendered an Award in BCB’s favour, awarding it its full claim, plus interest and costs (totalling approx. USD48 million), while in 2016, the Tribunal hearing the Dunkeld case, rendered an award totalling almost USD200m in our client’s favour.
  • The Republic of Poland in defending an investment treaty arbitration brought under the UNCITRAL Rules in the pharmaceutical sector. The investments that had allegedly been expropriated comprised numerous intellectual property rights. The tribunal dismissed the vast majority of claims and awarded the investors just a small fraction (less than 2%) of the amount claimed and left them to bear their own costs.
  • Millicom International Cellular S.A. and its Senegalese subsidiary, Sentel GSM S.A., in an ICSID arbitration against the Republic of Senegal. The case went to a merits hearing, and also involved related court litigation in Senegal. We negotiated, under very tight time constraints, a settlement with Senegal that put an end to over 12 years of disputes in Senegal and the ICSID arbitration itself. The disputes concerned the legality of Millicom’s operations in Senegal.

Recognition for our work

“Magic circle heavyweight fielding a well-respected arbitration practice. Highly rated for its skilful handling of investment treaty disputes, which form a large bulk of its work. Wins further recognition for its thriving sanctions practice and expert advice on sovereign immunity, Energy Charter Treaty claims and WTO matters. Its esteemed bench spreads across its extensive network of offices, with particular strength in London, Paris, Hong Kong and Singapore.”

Chambers Global 2018, Public International Law

Highly regarded for its stellar 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 Energy Charter Treaty claims, WTO cases, sovereign immunity concerns and international treaty drafting and negotiation.

Market sources say: "They are a Rolls-Royce outfit. They do a great job in high-value cases in this field."

Sources report the team is "super-efficient and very much attuned to the client."

Chambers UK 2018, Public International Law

“Prominent international team which maintains a respected arbitration practice. Has a wealth of experience acting for both claimants and respondents in investment treaty disputes… Commentators praise the firm, stating that "they undoubtedly have a fantastic practice," and describing the arbitration group as a "truly global practice."”  

Chambers Global 2018, International Arbitration

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