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Sub practice

Investment Treaty Arbitration

Allen & Overy has one of the world’s leading Investment Treaty Arbitration practices.

Our arbitration and public international law specialists have extensive experience of resolving investment disputes arising out of bilateral and multilateral investment treaties, having advised on more than 100 claims for both sovereign States and investors.

Our specialist team handles investment treaty arbitration proceedings under all the major rules, including the ICSID, UNCITRAL and Stockholm Chamber of Commerce (SCC) Rules, and in arbitrations administered by the Permanent Court of Arbitration. Recognised for our excellent track record of achieving successful outcomes for clients in these highly complex cases, we seek amicable, negotiated settlements and act at every stage of the investment arbitration process, including challenging and enforcing awards, appearing as advocates at hearings.

We have particular expertise in disputes arising under the Energy Charter Treaty (ECT), having acted on around a sixth of all ECT claims brought, including the first-ever arbitration and the first-ever collective claim under that Treaty.

We advise investors on the structuring and restructuring of overseas investments to secure investment treaty protection. We also advise States on the negotiation and drafting of international investment agreements and on accession to multilateral treaties. 

Our truly global practice includes specialists in London, Paris, Hong Kong, Dubai and Singapore.

Our experience includes advising:

  • More than 30 international investors, in 12 separate ECT claims against the Kingdom of Spain, concerning investments in the Spanish renewable energy sector. We have so far achieved significant damages awards for our clients in six of these arbitrations, with others still pending.
  • A global financial institution in a successful ICSID claim against Sri Lanka, for unlawful State interference with obligations under an oil hedging agreement between the bank and a State-owned oil company. Our client was awarded its claim in full, plus interest and its full legal costs, totalling around USD78 million. This was the first known investment arbitration to find that a complex financial instrument – in this case a derivatives contract – could be a protected investment.
  • Islamic Republic of Pakistan in successfully defending two related UNCITRAL investment arbitrations concerning gas import operations. The claims – valued at almost USD600 million - were dismissed entirely and the investors ordered to pay 90% of Pakistan’s costs. Challenge proceedings brought by the investors in the English courts (in which we also secured a security for costs order) were defeated.  
  • Nissan in its successful investment treaty claim against India, arising from the non-payment of various incentives due to Nissan after it built a major new plant in the Tamil Nadu state capital, Chennai. After our team secured an Award from the Tribunal, dismissing India’s jurisdictional objections to the claim, a settlement was reached, including a payment to Nissan in the region of USD200 million. 
  • Two oil and gas majors in their investment treaty claim against a South East Asian State and its state-owned national petroleum company in a substantial dispute arising from two Production Sharing Contracts for the exploration, development and production of oil and gas located offshore. The dispute was recently settled in return for a USD800 million payment to our clients. 
  • The United Arab Emirates in:
    • successfully defending an ICSID arbitration and subsequent annulment proceedings brought by a wealthy individual, who was seeking in excess of USD3bn in damages. The UAE successfully contested the jurisdiction of ICSID and a Final Award on jurisdiction was issued in the UAE’s favour. The subsequent annulment proceedings were also successfully defended; and 
    • two ongoing investment arbitrations brought against the UAE at ICSID. The claims arise from separate major infrastructure projects in the UAE and both cases are pending. 
  • The Republic of Azerbaijan in successfully defending two separate ICSID arbitration claims in the oil and gas and mining sectors. The claims, valued in excess of USD600m, were brought, respectively, under the Energy Charter Treaty and an investment contract. We succeeded in having the claims dismissed in their entirety in the ECT claim, while the contract-based claim was withdrawn by the claimant, with no payment or admission of liability by Azerbaijan.
  • The Sultanate of Oman in defending an investment treaty claim brought against it by Samsung Engineering, arising from a major project to refit an oil refinery. The claim was ultimately settled.
  • The Kingdom of Saudi Arabia in an investment treaty claim brought against it at ICSID by a Turkish construction company. The dispute, which is ongoing, arises from a major construction project in the Kingdom.
  • The Government of Korea in a claim for in excess of USD3.5 billion brought by a Malaysian real estate investor under the Malaysia-Korea bilateral investment treaty.
  • Dunkeld International Investments and British Caribbean Bank (BCB) in their separate and successful investment treaty claims against Belize (UNCITRAL Rules), arising from the nationalisation of Belize’s principal telecommunications company, Belize Telemedia. BCB was awarded its claim in full, plus interest and 100% of its costs (totalling almost USD50 million), while Dunkeld was awarded almost USD200 million in damages. The cases involved a number of related court actions in England, Belize and before the Caribbean Court of Justice, arising from certain anti-arbitration legislation enacted by Belize which sought to derail the claims.
  • Millicom International Cellular S.A. against the Republic of Senegal, in an ICSID arbitration which went to a merits hearing, and in related litigation in Senegal. We negotiated a settlement with Senegal that put an end to more than 12 years of disputes in Senegal and the ICSID arbitration itself, allowing Millicom to continue with its business. The disputes concerned the legality of Millicom's operations in Senegal.

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  1. Tier One, Public International Law, Legal 500 UK 2022
  2. International Arbitration Firm of the Year, Benchmark Litigation Asia-Pacific Dispute Resolution Awards 2020
  3. International Arbitration Matters of the Year, Benchmark Litigation Asia-Pacific Dispute Resolution Awards 2020