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Thomas Declerck

Partner

Brussels

Image of Thomas Declerck
Thomas Declerck

Partner

Brussels

Thomas specialises in white-collar crime, investigations and complex litigation, with a particular interest in cybersecurity.

Thomas has represented a broad range of high profile financial institutions, corporates and senior individuals on corporate and financial crime matters, including fraud, bribery and corruption, money laundering, market abuse, breaches of financial regulation and workplace misconduct. In addition to his extensive trial experience, Thomas regularly assists clients in implementing effective compliance programmes and conducting internal investigations. Thomas also has a long-standing practice in international sanctions and export controls, both stand-alone and in the context of M&A.

Thomas co-heads our Belgian cybersecurity practice. In close collaboration with A&O’s cyber specialists globally, he uses his established litigation and crisis management skills to advise clients across the spectrum of prevention, incident response, and litigation (whether civil or criminal).

Thomas is admitted to both the Brussels Bar and New York Bar.

Experience highlights

Related articles

A computer circuitboard

Blog Post: 11 October 2023

European Commission issues consultation on the European common cybersecurity certification scheme for ICT products

On 3 October 2023, the European Commission announced a public consultation regarding the draft implementing regulation (Draft Regulation) establishing the European Common Criteria-based cybersecurity…

Read more European Commission issues consultation on the European common cybersecurity certification scheme for ICT products

Blog Post: 30 August 2023

Webinar: Managing supply chain risk in the life sciences sector

Read more Webinar: Managing supply chain risk in the life sciences sector

Publications: 05 July 2023

Global sanctions on Russia accelerate focusing on sanctions circumvention and Russia responds

Read more Global sanctions on Russia accelerate focusing on sanctions circumvention and Russia responds

Publications: 07 June 2023

The ransomware hostage’s dilemma - should you pay the price?

Read more The ransomware hostage’s dilemma - should you pay the price?

Office

Brussels

Tervurenlaan 268A avenue de Tervueren
Brussels
1150

View office →

Qualifications

Professional

Admitted to the Brussels Bar, Belgium, 2011

Admitted to the Bar of the State of New York, USA, 2012

Academic

Master of Laws, Katholieke Universiteit Leuven (KUL) - Summa cum laude, 2010

LLM in International Legal Studies, New York University (NYU) - BAEF Francqui Foundation Fellow, Honorary Fulbright Scholar and Dean’s Graduate Award, 2011

Certificate Undergraduate Legal Studies (Erasmus Programme), King's College London, 2009

Pro bono

  • Advising a global non-governmental organisation focusing on supporting children without parental care and families at risk in relation to a broad range of regulatory risk.

Other noteworthy experience

Advising:

  • A listed Belgian telecom operator in multiple litigation proceedings challenging a planned EUR 2 billion investment in the roll-out of a new fiber-to-the-home network in Flanders and parts of Brussels
  • The former risk officer of Fortis Bank in criminal and civil proceedings initiated in the wake of the sub-prime crisis and Fortis’ take-over of ABN Amro in 2007-2008
  • A major financial services provider in responding to and mitigating various cyber incidents
  • A broad range of financial institutions, financial service providers and multinational corporates on navigating the ever more complex EU, UK and US sanctions landscape
  • An online gaming company in response to a distributed denial-of-service (DDoS) attack on its website servers
  • An energy storage company in response to a major ransomware attack severely disrupting its operations across Europe

Recognition