Zoe O’Sullivan QC is a robust and experienced trial advocate. Her practice extends across a wide field of commercial litigation and arbitration, including banking, oil and gas, company law and civil fraud. She is particularly noted for her expertise in software development disputes and is recommended by Chambers and Partners under Information Technology. She has a long and successful track record in both obtaining and opposing urgent applications for interim relief including world-wide freezing orders, anti-suit injunctions and applications to the court under section 44 of the Arbitration Act 1996. Zoe is registered as a Registered Foreign Lawyer with the Singapore International Commercial Court. She also sits as an arbitrator and is on the arbitration panels of the ICC and the LCIA.
"Very easy to work with and very hands-on. She is clearly fiercely intelligent, cares a lot about her cases and gets very absorbed in them." "She shows strong analytical skills in dissecting facts and applying legal principles." Chambers & Partners UK 2019 - Information Technology
"Very technically able and very client-oriented", "She's got the brain the size of a planet".
(Chambers UK 2018 - Information Technology)
"Has a growing IT practice that sees her handling cases concerning software development and licensing, major contractural disputes and outsourcing issues. She is also experienced at handling media tech issues."
(Chambers UK 2017 - Information Technology)
"She's formidably bright, writes very well and has a good balance of gravitas and humour." (Chambers UK 2016)
"She's able to have very practical and pragmatic conversations and to communicate effectively with clients." (Chambers UK 2016)
"An accomplished commercial silk with growing prominence in the technology sector, founded in part on her work in the landmark case of BSkyB v EDS. She is particularly experienced at handling software licensing disputes". (Chambers UK 2016)
"A very hardworking and strategic barrister, who is excellent on her feet and has a good way with clients" (The Legal 500 2015)
"Highly regarded for IT procurement disputes" (The Legal 500 2015)
Recent cases include:
Royal Devon & Exeter NHS Foundation Trust v Atos IT Services UK Ltd
Zoe was instructed as leading counsel for the defendant IT contractor in a substantial dispute over the digitisation of NHS patient records. Appeared at first instance and in the Court of Appeal on the trial of preliminary issues relating to the limitation of liability  EWHC 2197 (TCC).
CRS GT Limited v McLaren (2018)
Zoe was instructed as leading counsel for McLaren at the trial of a contractual dispute concerning the GT series road car, in which a supplier claimed £22 million in damages. The issues included whether a Heads of Ageement was binding, whether an agreement had been concluded by conduct, and quantum.
Inform CPI Ltd v London Borough of Tower Hamlets (Manchester Circuit Commercial Court, June 2018)
Zoe successfully defended Tower Hamlets Council at trial in a substantial software licensing dispute.
LCIA arbitration (hearing October 2018)
Zoe represented the Respondents in a claim for damages and unfair prejudice relief arising out of an agricultural joint venture in Ukraine, involving questions of alleged breach of fiduciary duty, alleged breach of the shareholders' agreement and reflective loss.
Zinc Holdings v AlixPartners (2018)
Zoe acted as part of the counsel team for the shareholders (including Vincent Tchenguiz) of companies in administration in an application to appoint conflicts administrators: issues included the merits of a swaps claim against the companies’ bank.
Bank of Baroda v Ind-Swift Laboratories (2018)
Zoe acted for the Indian defendants in a claim by the Bank to enforce an Indian judgment in England.
IT Contractor v FTSE-100 Insurance Company (confidential, settled 2018)
Zoe advised the claimant contractor in a dispute over business process outsourcing.
Rafael Advanced Defense Systems Ltd v Mectron (2017)
Acting for major Israeli defence contractor, obtained urgent interim relief in a dispute concerning the supply of navigation systems for the Brazilian Air Force.
Regional County Council v Serco (2017)
Acting for a County Council in an expert determination concerning the meaning and effect of a long-term IT outsourcing contract.
IBM v Insurance Company (confidential, 2017)
Advising IBM in a substantial dispute with an insurance client concerning the provision of “software as a service”.
Rockover Energy Limited v Maurel & Prom SA (2017)
Advising the defendant oil and gas producer in relation to a royalty dispute concerning a concession in Gabon.
Private client v GoldmanSachs (Ad hoc arbitration, 2017-2018)
For the Claimant in an international arbitration (Hong Kong seat) seeking damages from Goldman Sachs in respect of the delayed liquidation of derivatives contracts.
Bank of Dubai v Lazem (2018)
For the Defendant, resisting the enforcement of a Dubai court judgment.
Blomqvist v Zavarco Plc  BCC 542 and ongoing
Zoe acts for a minority shareholder in a series of actions about the ownership and control of a Malaysian fibre optic network. Part (2016) involved a Companies Court trial about the validity of the issue of shares in a plc and the estoppel created by the issue of share certificates. Part 2 (2018) concerns shareholder voting rights at the general meeting.
Bank of Moscow v Chernyakov  EWHC 1353 (Comm)
Acting for the defendant Russian businessman, resisting enforcement of Russian court judgments totalling £150 million on public policy and human rights grounds. Appeared on applications under the worldwide freezing order and at the summary judgment hearing. Part 2 of the case, currently under way, involves whether various shareholders are entitled to exercise voting rights at the meeting.
Rank Group v Gala Coral Group (2016)
Acting for the defendant to a tax warranty claim under a share sale agreement.
Sanctuary Housing Association v Ciber UK Ltd and Ciber Inc (2016-2017)
For Ciber in a case relating to the implementation of a SAP ERP system for a housing association. The complex issues were both contractual and technical.
Celtique Energie Weald Ltd v Magellan Petroleum (UK) Ltd (2015)
Acting for the claimant in a dispute under a Joint Operating Agreement relating to a proposed “fracking” project
Zoe has a working knowledge of French and Spanish.