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Portrait of Sarah Vasani

Sarah Vasani

Co-Head of International Arbitration

CMS Cameron McKenna Nabarro Olswang LLP
Cannon Place
78 Cannon Place - Cannon Street
United Kingdom
Languages English, Spanish

Sarah is Co-Head of International Arbitration at CMS Cameron McKenna Nabarro Olswang LLP, a role covering the U.K., Central and Eastern Europe, the UAE, Singapore, Turkiye, China, Brazil and Mexico. She is a seasoned international arbitration lawyer specialising in both international commercial arbitration and investor state disputes, representing clients before all key arbitral institutions including the LCIA, DIFC-LCIA, ICC, ICDR, SIAC, HKAIC, SCC, ICSID, and in arbitrations conducted under the UNCITRAL Rules, and foreign investment laws. She is dual-qualified in England & Wales and the U.S. (Texas and Washington D.C.), is a Solicitor-Advocate of the Higher Courts of England and Wales, and works in both English and Spanish.  

In addition to advocating for her clients' interests before international tribunals, Sarah advises clients on investment (re)structuring, and on strategies, options, and tactics for minimising the prospects of full-blown disputes. She is an adroit counsellor on managing and sharing the risks of arbitration through third-party funding, ATE insurance, and conditional-fee and damages-based agreements, and enforcing arbitral awards.  She has particular experience in energy, oil and gas, mining, and other large scale project disputes in Africa, the Middle East, Central Asia, the Indian Subcontinent, and Latin America and has represented many of the leading global energy and construction companies. Sarah regularly sits as party-nominated, sole, and presiding arbitrator.

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" 'superlative,' 'a star,' and an excellent lawyer, a superb team player, [who] puts her clients’ interests first at all times and will always go the extra mile for her clients. . . . . She is dedicated to her cases, totally unflappable and exudes confidence. She has the energy of three people and is tireless in achieving the best result for her clients."

Legal 500, 2020

Relevant experience

  • Representing an American technology company offering energy and water resource management services against a UAE ICT infrastructure and services integration company in a consolidated DIFC-LCIA arbitration relating to an alleged breach of a Teaming Agreement.  The dispute involves the provision of goods and services to an electricity and water authority in the MENA region.  The arbitration is governed by English law and seated in the DIFC. 
  • Acting for a major US-based energy services company against a Pakistani company in four DIFC-LCIA arbitrations arising out of five contracts and relating to the provision of goods and services for three gas processing facilities in Karachi, Pakistan. The arbitration is governed by English law and seated in Dubai. 
  • Representing the largest private Indian construction company in parallel ICC proceedings brought by an African state and its ministry of transportation in relation to a USD 3 billion port and rail project. The ICC proceeding is governed by Mozambican law and seated in Maputo. 
  • Advising a West African Communications and Technology Company in a dispute with a West African Central Bank in a high value LCIA arbitration concerning a technology project. The arbitration governed by Ghanaian law and seated London.
  • Advising the Ministry of Energy of a West African State in relation to an UNCITRAL arbitration seated in London concerning a dispute under a Build, Operate, Own and Transfer Agreement concerning a 300MW power station. 
  • Advising a Ghanaian oil and gas company in an UNCITRAL arbitration governed by Ghanaian law and seated London, against multinational lending institutions, in relation to the failure of the institutions to disburse loans related to a petroleum storage facility. The representation included defending an anti-suit injunction obtained by the lending institutions (on a without notice basis) before the English courts, allegedly in violation of the parties' LCIA arbitration agreement.
  • Advising India’s largest private oil and gas company in three UNCITRAL arbitrations against the Indian Government, one in relation to the company’s right to cost recovery under a PSC, another other relating to gas pricing, and the final in relation to a unitisation dispute.
  • Representing a major US-based oil and gas services provider against a Kazakh company in three LCIA arbitrations governed by English law and seated in London.  The dispute involved three separate agreements to provide goods and services to a gas processing and treatment facility in Kazakhstan (interim services, technical consultancy and O&M agreements).  
  • Representing a Mexican publishing distributor in a London-based LCIA arbitration against a Greek publishing house. The dispute concerned the breach of an exclusive distribution agreement, and expanded to include copyright and criminal matters. 
  • Advising a major US-based oil and gas services provider in dispute avoidance strategies in relation to an explosion at a gas processing plant in Pakistan.

Representative Investment Treaty Matters 

  • Advising a large US-based hedge fund on how to structure its investment in the renewables sector in Europe to obtain investment treaty protection, in light of the modernisation process of the Energy Charter Treaty and the Achmea decision by the Court of Justice European Union.
  • Advising one of the world's leading media and entertainment companies on restructuring its investment in the Middle East, and revising its web of layered disputes resolution clauses to maximise legal protection while minimising costs in the event of a dispute between the company and its contracting parties.

Other investment treaty cases include

  • Patel Engineering Limited v. Mozambique (rail and port project); 
  • Boonsom Boonyanit v. Malaysia (real estate investment and judicial misconduct – resulted in favourable settlement); 
  • Chevron Corp. & Texaco Petroleum Co. v. Ecuador (oil production and exploration, environmental remediation and corruption); 
  • Chevron Corp. & Texaco Petroleum Co. v. Ecuador (oil exploration and production and denial of justice); 
  • Chevron Bangladesh Blocks Twelve & Blocks Thirteen & Fourteen v. Bangladesh (natural gas pipelines); 
  • Waguih Siag v. Egypt (hotel resort development); 
  • El Paso Energy Int’l v. Argentina (hydrocarbon and electricity concessions, including PPAs); 
  • Murphy Exploration & Production Int’l v. Ecuador (hydrocarbons exploration and exploitation and windfall profits); 
  • S&T Oil Equipment & Machinery Ltd. v. Romania (chemical plant); 
  • Impregilo v. Argentina (water services concession); 
  • Impregilo II (Caminos de las Sierras) v. Argentina (highway infrastructure construction); 
  • Azurix v. Argentina (water and sewer services concession agreement); 
  • Exterran v. Venezuela (nationalisation of assets); 
  • Pan American Energy and BP Argentina Exploration v. Argentina (hydrocarbon and electricity concessions, including PPAs); 
  • Invesmart v. Czech Republic (banking)
  • Sempra Energy Int’l v. Argentina (natural gas supply and distribution);
  • Madagascar Oil Ltd. v. Madagascar (hydrocarbons exploration); 
  • CEAC Holdings Ltd. v. Montenegro (aluminium industry); 
  • Renco v. Peru (metallurgical complex refining and processing copper, lead, zinc and other metals)
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Memberships & Roles

  • Fellow of the Chartered Institute of Arbitrators.
  • Member of the Panel of Arbitrators for the CIArb's Business Arbitration Scheme.
  • Member of the International Mediation Institute (IMI) Investor-State Mediation Taskforce (2017-present), and head of the Singapore Convention subgroup (2018-present).
  • Pledge for Green Arbitration, Steering Committee.
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  • Editorial: The Energy Charter Treaty’s Uncertain Future in a World Going Green, Global Energy Law and Sustainability, April 2023 (co-editor of special edition with Lindsay Reimschussel). 
  • February 2017 - Protecting International Investments in a World Turning Insular, International Arbitration Quarterly Review. 
  • October 2016 - Inspired Arbitrator Choices: Addressing International Arbitration's Diversity Deficit, Young Arbitration Review, Edition 23.
  • August 2015 - African Oil Disputes in International Waters, Oil Review Africa.
  • July 2015 - The ITLOS: Patterns in the prescription of provisional measures and their implications for offshore oil and gas projects in disputed international waters, Young Arbitration Review, Edition 18.
  • April 2015 - The Emergency Arbitrator – An Effective Option for Urgent Relief, YOUNG ARBITRATION REVIEW, Edition 17.
  • 2014 - Energy Disputes in Times of Civil Unrest: Transitional Governments and Foreign Investment Protections, in Contemporary Issues in International Arbitration and Mediation – The Fordham Papers 2013, A. Rovine Ed., Martinus Nijhoff (co-author with C. Mouawad).
  • May 2010 - Bowing to the Queen: Rejecting the Margin of Appreciation Doctrine in International Investment Arbitration, Investment Treaty Arbitration and International Law, Vol. 3.
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Lectures list

  • June 2021 - Webinar on Energy Arbitration and Litigation Funding, Energy Disputes Arbitration Centre, Panellist. 
  • June 2021 - Infrastructure Projects and Investment Arbitration, Bucharest Arbitration Days 2021, Towards a Reform in Arbitration, Panellist. 
  • May 2021 - Mind the Gap: Geographic Diversity Between East and West in International Arbitration, Arbitrator Intelligence in conjunction with the ICC, Arbitral Women and the Racial Equality for Arbitration Lawyers. 
  • May 2021 - Arbitration vs Litigation: Which is better for the Planet?, Wagner-Sponsored Arbitrattoria Lunch, Key Note Speaker.
  • May 2021 - Unconscious Bias and Its Effect on Dispute Resolution, Panellist, London International Disputes Week. 
  • May 2021 - Enka v Chubb and Halliburton v Chubb, which will prove to be the most significant in the long-run and why, and how do they impact on London as an arbitration centre?, Panellist, London International Disputes Week. 
  • March 2021 - The 10 Golden Rules of Settling Investment Disputes with Host States, MUTE OFF Thursdays, Headline Speaker. 
  • March 2021 - Declaratory Relief: Requirements Procedure, and Purpose from Different Perspectives, Panellist, ICC Young Arbitrator's Forum.
  • January 2021 - Green Arbitrations Protocols Global Launch Webinar, Speaker.
  • January 2021 - Settling Investment Disputes – the Art of the Impossible, Panellist, Global Arbitration Review Interactive: BITs. 
  • January 2021 - Recent Regional Developments in Energy Arbitration, What's the Latest?, Moderator, ITA-IEL-ICC Joint Conference on International Energy Arbitration, Young Lawyers' Roundtable.
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  • 2006 - Juris Doctorate, Vanderbilt University Law School 
  • 2002 - Bachelor of Arts, International Relations, Michigan State University 
  • 2002 - Bachelor of Science, Agriculture & Natural Resources Communications,  Michigan State University 
  • Specialisations: Latin American and Caribbean Studies, Environmental Economics
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