Jonathan Clark

Joined firm 2007. Partner since 2014.

Jonathan has a strong and varied litigation and investigations practice advising a wide range of financial services and corporate clients. He has deep experience defending allegations of deliberate wrongdoing, having advised on criminal and regulatory investigations and litigation involving alleged corruption, fraud, cartel activity and tax evasion.

Jonathan’s litigation practice includes a focus on banking cases relating to complex derivatives transactions and benchmark manipulation, as well as multi-jurisdictional competition litigation in a number of sectors. He also advises clients in a number of different industries on appeals to the Competition Appeals Tribunal from decisions of the UK competition authorities.

Jonathan has particular interest and experience in advising clients in relation to ongoing business and PR issues in the context of live litigation or investigations.

Jonathan’s Investigations work highlights include advising:

  • British American Tobacco plc in connection with the SFO’s investigation of suspicions of corruption.
  • Rolls-Royce plc in relation to the criminal investigations by, and resolutions with, the SFO, US DoJ, and Brazilian authorities regarding allegations of bribery and corruption in overseas markets. The UK Deferred Prosecution Agreement was just the third such agreement in the UK (and by far the largest of the three) and the first to be concluded concurrently with the resolution of non-UK investigations.
  • Deutsche Bank A.G. on:
    • Regulatory investigations and resolutions relating to the setting of various interbank offered benchmark rates (including LIBOR and EURIBOR) over a number of years and across multiple jurisdictions; and
    • The first general LIBOR claim against multiple banks in England and Wales.
  • A global conglomerate against numerous allegations of fraud and corruption over a lengthy period in a number of jurisdictions, in an investigation and potential proceedings by a major multi-lateral development bank. 
  • A UK plc on responding to inquiries from the SFO, FCA and FRC regarding alleged false accounting practices.

Jonathan’s litigation work highlights include, in addition to those above, advising:

  • Essex County Council on a factually complex and technically intricate commercial dispute in the Technology and Construction Court.
  • Banco Santander Totta in a successful and ground-breaking case upholding the validity of interest rate swaps, which was the first case to be heard in the Financial List in the High Court and first appeal from that list to the Court of Appeal.
  • British Airways in its defence of multiple claims for damages in excess of £1 billion in relation to the alleged air cargo cartel, including the decision of the Court of Appeal in October 2015 to strike out significant parts of the claimants' case.
  • A global bank in relation to multiple, complex, high value claims arising out of the collapse of Kaupthing, an Icelandic Bank.

Jonathan joined Slaughter and May from Bell Gully in 2007, having qualified in New Zealand.

Jonathan is listed as a notable practitioner for financial services, banking litigation, commercial litigation and financial crime in both Chambers and Partners 2020 and Legal 500 2020, and is recognised as a Future Leader for Competition and Investigations in Who’s Who Legal.

Jonathan was identified as one of Global Investigation Review's 2017 "40 under 40"

The “fantastic” Jonathan Clark wins praise for his representation of corporations before domestic and international regulators. He is also adept at handling internal investigations. Chambers UK 2020, Financial Crime: Corporates

‘Jonathan Clark also is a clear thinker with excellent judgment’. Legal500 UK 2020, Regulatory Investigations and Corporate Crime