Sean O’Sullivan KC
Call 1997 Silk 2014
Instruct Sean
To instruct Sean please contact our clerks on +44 (0)20 7842 5555 or email [email protected].
Sean has a wide-ranging commercial practice, both as Counsel and increasingly also as an arbitrator, with a particular emphasis on:
- Shipping & Commodities
- Energy
- Insurance & Reinsurance
Reported cases include:
Eletson Gas v. A Ltd [2025] EWHC 1855 (Comm); Macquarie Bank v. Banque Cantonale Vaudoise [2024] EWHC 114; Havila Kystruten v, Abarca Companhia De Seguros [2022] EWHC 3196 (Comm); Ai Giorgis Oil Trading v. AG Shipping and Energy [2021] EWHC 2319 (Comm); Space Shipping v. ST Shipping and Transport [2021] EWHC 2288 (Comm); Galtrade v. BP Oil International [2021] EWHC 1796 (Comm); Altera Voyageur v. Premier Oil [2021] 1 Lloyd’s Rep. 451 Fluor v. Shanghai Zhenua Heavy Industry [2018] EWHC 1 (TCC); Neon Shipping v. Foreign Economic [2016] 2 Lloyd’s Rep 158; The “CV Stealth” [2016] 2 Lloyd’s Rep. 17; The “Proikonissos” [2015] 2 Lloyd’s Rep. 115; Expofrut v. Melville Services [2015] 2 CLC 218; Wuhan v. Emporiki Bank [2013] 1 Lloyd’s Rep. 161; [2014] 1 Lloyd’s Rep. 273; The “Saldanha” [2011] 1 Lloyd’s Rep. 187; Parbulk v. Kristen Marine [2011] 1 Lloyd’s Rep. 220; Guangzhou Dockyards v. ENE Aegiali I [2011] 1 Lloyd’s Rep. 30; Vitol v. Conoil [2009] 2 Lloyd’s Rep. 466; The “A Turtle” [2009] 1 Lloyd’s Rep. 177; The “Florida” [2007] 1 Lloyd’s Rep. 1; Gold Coast v. Naval Gijon [2006] 2 Lloyd’s Rep. 400; NB Three Shipping v. Harebell Shipping [2005] 1 Lloyd’s Rep. 509; BMBF v. Harland & Wolff [2001] 2 Lloyd’s Rep. 277.
Sean was nominated for Chambers & Partners’ Shipping Silk of the Year award in 2021, and has been nominated for the Legal 500 Shipping and Commodities Silk of the Year award in 2023 and 2025.
Comments in the directories in recent years have included:
- Sean is in a league of his own. He is second to none when it comes to oral advocacy.
- Super intelligent, phenomenally talented and easy to deal with
- One of the most outstanding commercial barristers of his generation, and a first rate advocate
- His delightful manner and credible advocacy ensure his many loyal instructing solicitors use him time and time again
- His bedside manner with clients is excellent
- Extremely personable, very clever and fantastic at getting to grips with the details in a case
- Sean is super user-friendly and very clear. He inspires a lot of confidence.
- An exceptional strategist
- Super bright and user-friendly
- He is simply fantastic. An absolute star
Shipping & Commodities
Sean is instructed in the full range of ‘dry’ shipping disputes concerning charterparties, bill of lading contracts and the equivalent, and commodities/sale of goods disputes more generally. He also deals with unsafe port claims, salvage claims, and other cases about marine casualties. He is instructed by shipowners and charterers, shippers, receivers, shipyards and brokers in disputes of all shapes and sizes, from demurrage disputes to the most technical disputes about massive shipbuilding projects. He is generally thought to be one of the leading shipping and shipbuilding silks.
Featured Shipping & Commodities cases
Acting for a hedge fund in relation to purchase options included in a series of bareboat charters.
Acting for a shipyard in claims following the termination of a series of newbuiliding projects because of delay obtaining refund guarantees.
Acting for a metals trader in a dispute about the quality of the product delivered.
Acting for a shipowner following a disputed withdrawal of a vessel for non-payment of hire.
Acting for a shipowner in relation to a limitation claim following a major casualty.
Acting for a slot charterer faced with a claim following a vessel fire.
Acting for the charterer of an LNG carrier in relation to a series of issues about performance and over-consumption.
Acting for a large shipowner in relation to claims about the discovery of corrosion following the sale of a tanker.
Acting for a major cruise line which sold two vessels to another cruise line, resulting disputes about the warranted condition.
Acting for a bareboat charterer on a redelivery claim concerning two ferries.
Acting for a buyer in relation to the cancellation of a newbuilding project by a Spanish shipyard.
Acting for a charterer on a major unsafe port claim arising out of a casualty and related pollution incident in a remote part of the world.
Acting for a seller in an MOA dispute concerning the impact of COVID on completion of the sale.
Acting for the charterer of an LNG tanker in relation to a dispute about redelivery notices and the market for such vessels.
Acting for a bank providing financing to a major shipowner in relation to the recoverability of hedging break costs.
Acting for a shipowner in a claim under an LOU, following on from a huge misdelivery claim.
Acting for a charterer in relation to the cancellation of a bareboat charter for a very sophisticated diving support vessel, with issues about the networking of the dynamic positioning system.
Energy
Sean is instructed in a range of upstream disputes but especially shipbuilding, ship conversion, ship repair, ship sale and purchase, and offshore construction disputes which have an energy aspect as a result of the service for which the ship or project is intended.
His clients include shipyards, buyers, owners and designers and he has been involved in disputes about all aspects of the different projects.
He also acts for oil companies, traders and contractors in relation to disputes about oil exploitation and drilling for or transportation of oil and gas. He is instructed in a number of cases concerning sales of oil and gas and other fuels including coal and biofuels.
Featured Energy cases
Acting for the operator of an offshore accommodation unit in relation to claims for lost time arising out of damage to the gangway in heavy weather.
Acting for a major energy company on a dispute about the abandonment of a well-stimulation project as a result of problems with a diving support vessel which had been chartered for the work.
Acting for a fuel oil trader in relation to sales of fuel oil into Senegal.
Acting for an African mining company in relation to claims and counterclaims arising out of a contract for the purchase and transportation of duty free fuel.
Acting for an African National oil company in a dispute with a major contractor about the cost of a plugging and abandonment project for one of its fields.
Acting for a major shipowner in relation to a dispute about the cancellation of a newbuilding project for multiple drillships.
Acting for a Korean shipyard in relation to a dispute about the deliverability of a FSO platform.
Advising a Chinese shipyard on a series of sales of offshore accommodation and drilling units.
Acting for an oil trader in litigation concerning supply of off-spec low sulphur fuel oil.
Acting for a Korean shipyard in relation to various disputes about the construction of a rig installation/ decommissioning vessel.
Acting for a shipyard in an ICC arbitration concerning the construction of an FPSO for use in Iraqi waters, with issues about the reasons for delay and the consequences of delivery incomplete.
Insurance & Reinsurance
Sean is variously instructed in coverage and other insurance related disputes, both marine and non-marine, relating to both primary layers as well as reinsurance.
Featured Insurance & Reinsurance cases
Acting for an insured on a large business interruption claim arising out of a generator engine failure.
Advising on rights of subrogation under an H&M policy following a collision.
Advising a PI insurer in relation to coverage in respect of a claim against a yacht broker.
Acting for a reinsurer on a number of claims on a XL policy protecting a book of E&O covers.
Acting for a reinsurer in relation to the rescission of a facultative arrangement for reinsuring private healthcare insurance in the UAE on grounds of non-disclosure/ misrepresentation.
Arbitral Appointments
Sean also receives an increasing number of arbitration appointments in disputes within the areas of practice outlined above. By way of example, he was appointed by the parties as sole arbitrator in an ICC arbitration between two entities based in the Middle East concerning an offshore project, and he has been appointed as sole arbitrator in a LCIA case between oil traders. He is currently acting as chairman in several LMAA arbitrations, in an Arias arbitration about the reinsurance of COVID losses, and he was appointed by the ICC Court as chairman in an arbitration concerning various bunker sales.
He has been appointed by the parties in several LCIA arbitrations, including disputes about structured finance and sales of commodities. He has also been appointed by the parties in number of LMAA arbitrations, including a claim concerning a luxury yacht and a dispute about a ship management agreement, and a series of related arbitrations about a chain of sales.
He is a supporting member of the LMAA. In 2018, Sean was also admitted as arbitrator on the EMAC Panel.
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Instruct Sean
To instruct Sean please contact our clerks on +44 (0)20 7842 5523 or email [email protected].
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