Jeffery Onions KC

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Jeffery Onions KC

Barrister

Call 1981 Silk 1998

Jeffery Onions undertakes a wide range of complex commercial and company law disputes work both as an advocate and in an advisory context.  He has particular expertise in banking and finance, company and insolvency, commercial litigation, civil fraud, energy/oil and gas, insurance and reinsurance, shareholder disputes and international arbitration. He also accepts appointments as an arbitrator and expert.

Recent cases include: 

  • Henderson & Jones v Ross and Others
    For the Claimant in an 18 day trial relating to transactions involving allegations of defrauding creditors arising from a corporate restructure and of dishonest assistance involving a major bank and a firm of solicitors. Awaiting judgment.
  • PCP/Staveley v. Barclays Bank plc appearing at trial (with Alexander Polley and Oliver Butler) for Barclays in this high profile dispute involving substantial claims arising from the alleged role of PCP and Ms Steveley in assisting Barclays to raise £7 billion a capital raising conducted by the bank during the 2008 financial crisis (one of The Lawyer's top cases of 2019 and 2020).
  • Acting in an international arbitration (ICC) involving Chinese investments in foreign based funds involving issues of contractual construction, rectification, foreign law and fraud.
  • Acting for the claimant in a substantial fraud claim in relation to Kazakhstan mining assets raising issues of Kazakh law, jurisdiction and proper law.
  • Acting for excess insurers in a confidential dispute relating to costs coverage issues.
  • Advising on issues related to the quantum of damage arising from an international arbitration relating to substantial shipbuilding contract and fraud/bribery related claims.
  • Acting in and confidential dispute involving a major infrastructure provider in relation to issues arising with the entities using the infrastructure, dealing with contractual claims by those entities and arising out of complex scheme established for the use of the structure and advising on strategies to avoid and minimise claims.
  • Acting in a substantial arbitration involving a dispute between private equity funds in relation to the purchase of telecom towers in Africa.
  • Advising on contractual construction issues arising from a joint venture agreement in relation to a substantial public procurement exercise and the effect of challenges to the validity of the procurement exercise.
  • Advising an electricity provider on claims arising from damage to the provider’s infrastructure.


  • Examples of Recent Cases

    • Arbitration

      • ICC Proceedings
        International arbitration involving Chinese investments in foreign based funds involving issues relating to the export and repatriation of funds from and to China, the establishment and operation of investment funds and of contractual construction, rectification, foreign law and fraud.
      • Substantial arbitration involving a dispute between private equity funds in relation to their involvement in the purchase of telecom towers in Africa.
      • Advising on issues related to the quantum of damage arising from an international arbitration relating to substantial shipbuilding contract and fraud/bribery related claims.
      • Acting in a substantial arbitration relating to oil and gas exploration off the coast of Libya, raising factual issues relating to the drilling of wells, the abandonment of prospects and relations with governmental authorities.as well as issues of contractual construction.
      • Acting in a substantial arbitration relating to wind farms in the North Sea raising issues of force majeure.
      • Acting in a substantial arbitration relating to the failure of an installation in the North Sea raising complex technical issues relating to meteorological hazards and wave motion and wave motion as well as contractual issues relating to the allocation of risk.
      • Acting in a substantial arbitration involving construction and contractual issues related to a failed offshore mooring system, an FPSO, which tankers moored against to transfer oil from subsea-involved design issues, metal issues and weather issues. 
    • Banking and Financial Services

      PCP/Staveley v. Barclays Bank plc 
      For Barclays (with Alexander Polley and Oliver Butler) in this high-profile dispute involving substantial claims arising from the alleged role of PCP and Ms Staveley in assisting Barclays to raise £7 billion a capital raising conducted by the bank during the 2008 financial crisis (one of The Lawyer’s top cases of 2019 and 2020) raising issues of fraudulent misrepresentation, causation and the valuation loss of a chance.

      • McKillen v Maybourne Finance Ltd [2012] EWCA Civ 864
        Appearing for Maybourne Finance Ltd in a case involving the interpretation of a loan agreement and issues of novation. Included a hearing before the Court of Appeal dealing with the construction of articles of association.
      • Advising in relation to claims arising from the London Interbank Offered Rate (LIBOR) scandal.
      • Acting for Kaupthing in claims brought by the Tchenguiz brothers concerning issues of corporate governance.
      • Alfa Overseas Investments v Deutsche Bank [2008-9] (Ch). 
        Appearing for Deutsche Bank in proceedings concerning a US$350m loan secured against shares in hedge funds.
      • Advising in relation to a potential judicial review of a decision whether to issue a banking license in Gibraltar.
      • UBS v. Tank & Rast (2008) (Comm)
        For the borrower in a leading "credit crunch" case about a lender's ability to transfer its participation in a syndicated loan.
      • Redwood Master Fund Ltd & 5 Ors v (1) TD Bank Europe LTD (2) UPC Distribution Holding BV (3) UPC Financing Partnership [2002] All ER (D) 141
        A case involving whether minority lenders under a syndicated loan facility agreement were bound by a decision of the majority lenders to waive a borrower's default.  Also dealt with corporate governance issues.
      • (1) Silven Properties Ltd (2) Chart Enterprises Incorporated v (1) Royal Bank of Scotland Plc (2) Nigel Vooght and Ors [2002] All ER (D) 36
        A dispute involving whether a bank had agreed that it would not require repayment of borrowings 'on demand' or that it would allow the opportunity to refinance before appointing receivers).
    • Commercial Fraud

      PCP/Staveley v. Barclays Bank plc 
      For Barclays (with Alexander Polley and Oliver Butler) in this high-profile dispute involving substantial claims arising from the alleged role of PCP and Ms Staveley in assisting Barclays to raise £7 billion a capital raising conducted by the bank during the 2008 financial crisis (one of The Lawyer’s top cases of 2019 and 2020) raising issues of fraudulent misrepresentation, causation and the valuation loss of a chance.

      • Advising in 2020 in relation to a potential group action in relation to the activities of insurance brokers and raising issues of breach of fiduciary duty, quantum of loss and equitable damages.
      • Acting in 2020 in a confidential dispute in relation to agreements for the operation of hotels and the provision of services to hotels, raising issues of contractual construction, agency and the nature and extent of fiduciary duties, including obligations to allow the inspection of documents.
      • Musst Holdings Ltd v Astra Asset Management & Ors
        Acting in 2020 for the defendant investment managers in interlocutory proceedings in a claim relating to fees for allegedly introducing investors to a unique type of fund, raising issues relating to contractual construction and investment policies.
      • ICC Proceedings 
        International arbitration involving Chinese investments in foreign based funds involving issues of contractual construction, rectification, foreign law and fraud.
      • Advising on contractual construction issues arising from a joint venture agreement in relation to a substantial public procurement exercise and the effect of challenges to the validity of the procurement exercise.
      • Acting for the claimant in a substantial fraud claim in relation to Kazakhstan mining assets raising issues of Kazakh law, jurisdiction and proper law.
      • Advising on possible liabilities in relation to the construction of a substantial infrastructure project and the extent of indemnities in relation thereto.
      • Apache Beryl v Marathon
        Acting in a non-party heavily involved in an expedited trial in the Commercial Court relating to the proposed purchase by of significant infrastructure assets in the North Sea and raising issues as to reasonable consent to transfers, pre-emption, de-commissioning costs and the reliability of financial models of future earnings from the transportation of gas. Please see http://www.bailii.org/ew/cases... for further information.
      • FTSE
        Acting for FTSE in a dispute relating to the rights in and the use of intellectual property rights under and after the termination of a co-operation agreement relating to data used to produce "green indices".
      • Advising in 2017 and 2018 relation to a the construction of a major potential infrastructure project and the terms relating thereto 2017, with particular reference to the indemnity to be provided by a public authority to .
      • Acting in 2017 in a dispute relating to the licensing of pharmaceutical products in foreign jurisdictions, including the construction and effect of indemnities in transfer agreements.
      • Advising in 2017 in relation to a dispute between a major advertising company and a major computer company in relation to the terms of a long terms co-operation and service agreement including the provision of out-sourcing services.
      • SP Limited v Swinton 
        Acting for a major insurer in a claim relating to the termination of an out sourcing agreement relating to insurance services involving an application for a mandatory injunction and raising complex factual issues and issues of contractual construction, including issues relating to exemption clauses.
      • For IBM in a contractual dispute with The National Trust, who alleged that IBM failed to deliver the services in accordance with its obligations & misrepresented its capabilities under the Master Services Agreement and Call-Off Contract in relation to provision of services (incl. hosting an application support services in relation to the NT's new Oracle customer relationship management system).
      • IBM v Fujitsu [2014] EWHC 752
        Acting for IBM in a substantial computer contract dispute raising issues as to the construction and effect of exemption clauses.
      • Network Rail Infrastructure Ltd v Simon Handy Acting for Network Rail in a substantial claim arising from a significant land slip at a colliery that damaged Network Rails track and caused substantial repair and delay costs. The claim raised numerous complex factual issues as well as issues relating to insurance, the Third Part Rights Against Insurers Act and insolvency.  Please see https://www.lawtel.com/UK/Searches/3304/AC0146249 for further information.
      • Acting for a provider in a dispute relating to a substantial computer up-grade project involving technical issues and issues relating to the construction and effect of exemption clauses.
      • Lebara Mobile Ltd v Lycamobile UK Ltd [2015] EWHC 3318 (Ch)
        Acting for Lyca in successfully defending injunction proceedings alleging numerous causes of action under English and certain EC laws. Under English Lebara alleged, in particular, conspiracy to injure, interference with its business by unlawful means, unlawful means conspiracy and a direct claim under the Privacy and Electronic Communications (EC Directive) Regulations 2003.
      • Network Rail Infrastructure Ltd v Conarken Group Ltd [2011] EWCA Civ 644; [2012] 1 All E.R. (Comm) 692. 
        Acting for Network Rail in a test case relating to the recoverability in tort of economic loss in the form of compensation payable pursuant to complex contractual provisions governing the relations between Network Rail and Train Operating Companies following damage and disruption to train services as a result of "bridge strikes".
      • Acted for British Gas in its widely publicised dispute with Accenture in relation to its computerised customer billing system, GB Gas Holdings Ltd v Accenture [2010] EWCA Civ 912, a case involving complex issues of contractual construction and issues relating to IT hardware and software systems.
      • Acted for the Post Office in Tele 2 International Card v The Post Office [2009] EWCA Civ 9, a case involving contractual no waiver clauses.
    • Company and Insolvency

      • Acting in a confidential dispute for directors of a substantial company in relation to allegations of breach of director's duties and potential unfair prejudice involving banking arrangements in Eastern Europe.
      • McKillen v Maybourne Finance Ltd 
        [2012] EWCA Civ 864, appearing for Maybourne Finance Ltd in a case involving the interpretation of a loan agreement and issues of novation. Included a hearing before the Court of Appeal dealing with the construction of articles of association.
      • John Thompson & Janet Thompson v. Goblin Hill Hotels Limited [2011] UKPC 8
        The appellants started these proceedings in the Supreme Court of Jamaica claiming declarations that (i) the assessments and special assessments made by GHHL in the years 1994 to 2001 were excessive, because they had not been calculated in accordance with the lease and articles of association of the company properly construed and (ii) the company had wrongfully forfeited their lease and sold their shares. Appeal looked at question of the true construction of articles of association.
      • Advising in relation to a substantial joint venture dispute concerning the printing of a national newspaper.  Concerned potential court challenges by a minority shareholder.
      • Acting in relation to a politically sensitive shareholder dispute in Hong Kong involving Hong Kong Chinese and Mainland Chinese parties.  The dispute included allegations of fraud, breaches of fiduciary duty, breaches of directors duties and obligations to minority shareholders across a number of different actions, including a derivative action.
      • Harley Street Capital Ltd v. Tchigirinsky & Ors [2005] EWHC 1897 (Ch)
        Successfully defeated attempts to continue a derivative action, concerning the conduct of Russian subsidiaries. Specifically the alleged fraudulent acquisition of an oil field from Roman Abramovich's Sibir Energy plc, in the context of a minority shareholders action.
      • Advising on a contested take-over involving interpretation of the City Code on Take-overs.
    • Civil Fraud and Investigations

      • Acting in 2020 for a foreign national resident in England in relation to the effect and possible enforcement (including freezing injunctions) in England of foreign criminal and related civil claims arising from the operation of a substantial foreign bank.
      • Acting for the claimant in a substantial fraud claim in relation to Kazakhstan mining assets raising issues of Kazakh law, jurisdiction and proper law.
      • Acting in 2017 for defendants in a substantial alleged fraud involving foreign property interests.
      • Acting in 2016 for defendants in a substantial alleged financing and investment fraud.
      • Acting for the successful defendant in Al Gaood v Innospec [2014] EHWC 3147 Comm A Substantial unlawful means conspiracy involving allegations of bribery in Iraq follwoing the second Gulf War in relation to the supply of chemicals.
      • Tullet Prebon v BGC Brokers.  Acting at first instance [2012 IRLR 648] for the Claimants in a claim alleging unlawful means conspiracy based on inducing or procuring employees to act in breach of their contracts of employment that also raised issues of sham constructive dismissal, the enforcement of garden leave injunctions and the grant of “no poach” injunctions.
      • Secretary of State for Justice v. LSM Professional Partners [2011] EWHC 983 (QB); [2010] EWHC 1781 (Ch)  Acting for Topland Group Plc in a substantial conspiracy claim related to an alleged property fraud, bribery and dishonest assistance.
      • Kaupthing Bank 
        Acting for Kaupthing, defending claims made the Tchenguiz Discretionary Trusts (TDT).
      • Newsat Holdings Limited & Ors v. Zani [2006] 1 Lloyd's Rep 707 
        For Claimant, in proceedings alleging fraud in relation to licensing of geostationary communications satellite rights. Jurisdiction and world wide freezing orders
      • Harley Street Capital Ltd v. Tchigirinsky & Ors [2005] EWHC 1897 (Ch)
        Successfully defending a derivative action, concerning the conduct of Russian subsidiaries. Specifically the alleged fraudulent acquisition of an oil field from Roman Abramovich's Sibir Energy plc, in the context of a minority shareholders action.
    • Energy and Natural Resources

      • Apache Beryl v Marathon 
        Acting for a non-party heavily involved in an expedited trial in the Commercial Court relating to the proposed purchase of significant infrastructure assets in the North Sea and raising issues as to reasonable consent to transfers, pre-emption, de-commissioning costs and the reliability of financial models of future earnings from the transportation of gas. Please see http://www.bailii.org/ew/cases... further information.
      • Petrobras v Oil Search
        Acting for a substantial oil and gas exploration and exploitation company in relation to the termination of joint venture arrangements relating to the exploration and drilling of oil wells in Libya.
      • Low Carbon Contracts v NNG 
        Acting for LCCC in an arbitration relating to the termination of an agreement for the development of a wind farm in the North Sea and raising issues as to force majeure. Please see  http://www.bailii.org/ew/cases... further information.
      • Acting for the operators of infrastructure in confidential disputes relating to send or pay provisions and tariff re-opener/cost based tariffs in oil and gas transportation agreements.
      • Acting in confidential disputes relating to green energy projects, including waste recycling and wind farm technology.
      • Acting in confidential disputes relating to issues arising from decommissioning costs in the North Sea and MER UK.
      • Acting in confidential dispute relating to the transfer of interests in infrastructure in the North Sea and the equity funding of the transfer of interests, involving the nature and extent of continuing liabilities and the effect of indemnities.
      • Acting in confidential dispute relating to the possible termination of a long term agreement for the supply of uranium and the related financing agreements.
      • Acting in a substantial arbitration involving a North Sea FPSO raising complex issues of contractual construction and technical issues relating to the effect of weather and sea states on operation.
      • Advising on the effect of termination and forfeiture provisions/penalty clauses on oil and gas JOAs.
      • Lyondellbasell Industries Holdings B.V - v - (1) Shell Petroleum N.V. (2) Deutsche Shell GmbH (3) Shell Montell Holding I.B.V (4) Shell Overseas Holdings Limited (5) BASF SE (formerly basf aktiengesellschaft) (6) BASF Beteiligungsgesellschaft mbH
        Acting for Shell and BASF (The Defendants / Sellers) in a claim under an environmental indemnity arising from the sale of a plastic business and relating to a large number of sites throughout the world. Issues of contractual construction due for determination in July.
      • Premier Oil
        Acting in an injunction proceedings relating to an oil and gas project. The claim related to the obligations of the parties under joint operating and loan agreements.
      • Advising on the construction and effect of cost based gas tariff re-opener provisions in gas sales agreements.
      • Acting in a dispute relating to the interpretation of of a joint participation agreement in relation to North Sea interests.
      • Acting in arbitrations involving  Non-Fossil Fuels Obligations, Renewable Obligations Certificates & Renewable Obligations Order.
      • Centrica & BGTL v. Premier Power [2006] EWHC 3068 (Comm), [2006] All ER (D) 23 (Dec); [2007] EWHC 527 (Comm) 
        For PPL, in relation to the construction of a Gas Supply Agreement in light of Network Code changes and postalisation in Northern Ireland.
      • Advising on gas sales agreements, tolling agreements, pre-emption rights, transportation contracts and disputes relating to floating production platforms and drilling vessels, electricity supply contracts, the Electricity Supply Act 1980, the Gas Act 1986 and the Utilities Act 2000.
      • Appearing in arbitrations under the London Court of International Arbitration (LCIA) Rules, the Stockholm Arbitration (SCC) Rules and the International Chamber of Commerce (ICC) Rules of Arbitration.
    • Insurance and Reinsurance

      • Acting for excess insurers in a confidential dispute relating to costs coverage issues arising from a major incident involving substantial damage and loss of life.
      • Network Rail Infrastructure Ltd v Simon Handy Acting for Network Rail in a substantial claim arising from a significant land slip at a colliery that damaged Network Rails track and caused substantial repair and delay costs. The claim raised numerous complex factual issues as well as issues relating to insurance, the Third Part Rights Against Insurers Act and insolvency. Please see https://www.lawtel.com/UK/Sear... for further information.
      • Cantarell Project – AIG –v- Zurich, XL/Winterthur, Wellington & Sompo
        Concerning a reinsurance of a Marine, Construction and Operational Insurance Policy covering a nitrogen separation plant in Mexico.
      • European Mutual Association for Nuclear Insurance –v- Hinton Insurance Limited
        Acting for European Mutual. Proposed proceedings arise from a likely claim for an indemnity under two reinsurance policies issued by EMANI to Hinton. This potential claim arises from the leakage of nitric acid containing dissolved nuclear material into a bunded secondary containment area.
    • Jurisdiction and Conflict of Laws

      • Acting for the claimant in a substantial fraud claim in relation to Kazakhstan mining assets raising issues of Kazakh law, jurisdiction and proper law, and in particular, the interrelationship of the gateways for service out of the jurisdiction and the evidence (including evidence of foreign law required to establish jurisdiction to serve proceedings out of the jurisdiction).
      • Acting in a claim involving the setting aside of the service of English proceedings in a foreign jurisdiction.
      • Alfred Dunhill v Diffusion Internationale [2002] 1 All ER (Comm) 950 (Article 5(3) of the Brussels/Lugano Convention and negligent mis-statement)
      • RZB v National Bank of Greece [1999] 1 LLR 408 (Shipbuilding contract, loan agreement and Articles 5(1) and 5(3) ).
    • Information Technology

      • Acted for Swinton Group Ltd v SSP. SSP were threatening to commence proceedings seeking an injunction and damages of approximately £30 million, an application for an interim injunction against Swinton to prevent various alleged breaches of a Licence Agreement unless Swinton provides certain undertakings.
      • The National Trust for Place of Historic Interest or Natural Beauty v IBM United Kingdom Ltd
        Acted for IBM. The national trust had alleged that IBM failed to deliver the services in accordance with its obligations & misrepresented its capabilities under the Master Services Agreement and Call-Off contract in relation to provision of services (Incl. hosting and application support services in relation to the NT's new Oracle customer relationship management system). As a result TNT was seeking to recover from IBM losses it claims to have suffered.
      • Acted for IBM in IBM v Fujitsu [2014] EWHC 752, a substantial computer contract dispute raising issues as to the construction and effect of exemption clauses.
      • Acted for Lyca in Lebara Mobile Ltd v Lycamobile UK Ltd [2015] EWHC 3318 (Ch) in successfully defending injunction proceedings alleging numerous causes of action under English and certain EC laws. Under English Lebara alleged, in particular, conspiracy to injure, interference with its business by unlawful means, unlawful means conspiracy and a direct claim under the Privacy and Electronic Communications (EC Directive) Regulations 2003.
      • Acted for British gas in its widely publicised dispute with Accenture in relation to its computerised customer billing system, GB Gas Holdings Ltd v Accenture [2010] EWHC Civ 912, a case involving complex issues of contractual construction and issues relating to IT hardware and software systems.
      • Acted for IBM concerning a Cloud computing deal where a dispute arose about the agreed benefits and savings and how they were calculated.
    • Professional Liability

      • Network Rail Infrastructure Ltd v Simon Handy 
        Acting for Network Rail in a substantial claim arising from a significant land slip at a colliery that damaged Network Rails track and caused substantial repair and delay costs. The claim raised numerous complex factual issues as well as issues relating to insurance, the Third Part Rights Against Insurers Act and insolvency. Please see https://www.lawtel.com/UK/Sear... for further information.
      • Acted for Network Rail in Network Rail v Conarken [2012] 1 All ER (Comm) 692
        Sccessful claims for damages in negligence arising from damage to the rail infrastructure raising issues of economic loss, remoteness and the law of penalties.
      • Nelson Group Services (Maintenance) Ltd v BG Plc.
        Involving detailed forecasts of projected sales figures that were the subject of an implied (and false) representation regarding the accuracy of the facts and assumptions on which those forecasts were based.
      • Corbett v Bond Pearce [2001] 3 All ER 769 (solicitor's negligence).
  • Other Experience

    Acting and advising on a number of expert determinations relating to business sale agreements; a substantial management consultancy dispute, disputes relating to Article 5 and Articles 21/22 of the Brussels/Lugano Convention; and a number of cases involving obligations and exclusions relating to computer software and hardware.

    Acting as an expert in disputes relating to green energy and waste disposal/conversion into electricity.

    Acting as sole arbitrator in a dispute relating to the construction of an generating station based on the generation of electricity from waste.

    Acting as arbitrator in a Bermuda Form arbitration.  

    Acting as a mediator in relation to claims arising from the allegedly fraudulent marketing of a foreign based investment fund.

    He is a member of the London Common Law and Commercial Bar Association (LCLCBA), the Administrative Law Bar Association.

  • What the Directories Say

    "Jeffery brings considerable experience and authority to bear in any case. He very clearly saw at the outset what the dispute was actually about and was always thinking six steps ahead." (Commercial Litigation, Chambers UK 2024)

    "Very easy to deal with, he's hard working and extremely thorough." (Commercial Litigation, Chambers UK 2024)

    "Brilliantly user-friendly and tech-savvy for someone of his seniority," he's "a lawyer with great cross-examination skills who sees the whole picture." (Commercial Litigation, Chambers UK 2022)

    "Phenomenally clever, good fun to work with and incredibly versatile." "He is an absolutely fantastic advocate who is very skilful in his arguments." (Commercial Litigation, Chambers Global 2021)

    "He has a ferocious intellect and an impressive ability to assimilate a huge volume of factual matter in order to distil focused and valuable advice." "He is incredibly knowledgeable in the energy sector and is excellent at distilling complex legal points into pragmatic commercial advice." "He is an excellent lawyer who gives very succinct advice." (Energy & Natural Resources, Chambers UK 2022)

    "Amazing - in the top category of KCs." "Pragmatic, down-to-earth and firm with clients when he needs to be." "Extremely responsive, client-friendly and steeped in the oil and gas industry." (Energy & Natural Resources, Chambers Global 2021)

    "When solicitors need a real heavyweight, Jeffery is one of their top choices. He will never shy away from a fight if it needs to be had, and his forensic legal analysis is uncompromising." (Commercial Litigation, Legal 500 2021)

    "Brilliant, fully deserving of his reputation, he is one of the best cross-examiners at the commercial Bar." (Energy, Legal 500 2021)

    An impressive and very experienced barrister who is never afraid to take a view where others may sit on the fence.” (Commercial Litigation, Legal 500 2020)

    "His analysis is extremely thorough and detailed, he's aware of the commercial drivers for the client, and he thinks about the problem in the round." "He gets stuck in, and he's a heavyweight who is very good on technical points." (Commercial Disputes Resolution, Chambers UK 2020)

    "A huge support to the team throughout and his analysis was extremely forensic."  (Commercial Litigation, Legal 500 UK 2019-2020)

    "He is phenomenally intelligent yet client-friendly." "He is always willing to take time to bring people up to speed and is good at handling clients." "He is steeped in the oil and gas industry."  (Energy & Natural Resources, Chambers UK 2020)

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