William RM Long

WILLIAM LONG is a global co-leader of Sidley’s highly ranked Privacy and Cybersecurity practice and heads the EU Data Protection group. He also serves on the firm’s COVID-19 Task Force. William advises international clients on a wide variety of GDPR, data protection, privacy, information security, social media, e-commerce and other regulatory matters.William has been a member of the European Advisory Board of the International Association of Privacy Professionals (IAPP) and on the DataGuidance panel of data protection lawyers. He is also on the editorial board of e-Health Law & Policy and also assists with dplegal (“data privacy” legal), a networking group of in-house lawyers in life sciences companies examining international data protection issues.William’s experience includes advising:EQT Private Equity and PRO Unlimited in connection with PRO Unlimited’s acquisition of Workforce Logiq.Numerous international companies on the GDPR.Companies on data privacy issues with Big Data, Internet of Things and profiling. A global e-commerce company on dealing with an international data security breach.A global manufacturing company on a global data protection project, including implementation of Binding Corporate Rules.William was previously in-house counsel to one of the world’s largest international financial services groups. He has been a member of a number of working groups in London and Europe looking at the EU regulation of e-commerce and data protection and spent a year at the UK’s Financial Law Panel (established by the Bank of England) as assistant to the chief executive working on regulatory issues with online financial services.William has received acknowledgement from numerous industry ranking guides:BTI Client Service All-Stars 2022 – Named in this annual report for providing incomparable level of client service excellence. Chambers UK 2022 – Ranked for Data Protection and Information Law, with sources telling the publication “he combines his great expertise with a very friendly approach in dealing with clients.”Chambers UK 2021 – Ranked for Data Protection and Information Law where commentators say “he is really good all round and has subject matter expertise” and “his guidance is thorough and he makes a difficult topic easily digestible.”The Legal 500 UK 2022 – Recognized for Data protection, Privacy and Cybersecurity, where one client comments that he “is an international top expert in the field of privacy and data protection: he combines his great expertise with a very friendly approach in dealing with clients, which is very important for a positive relationship.”Best Lawyers 2022 – Listed for Privacy & Data Protection Law.Who’s Who Legal 2022 – Ranked as a Global Leader for Data Privacy and Protection; Data Security and Data Information Technology.Who's Who Legal 2021 – Ranked as Thought Leader for Data Privacy & Protection, Data Security.William is also the author of a new book on the EU General Data Protection Regulation and a contributor to a number of books on data protection, including leading legal textbooks published by BNA in the area of privacy, cloud computing and the use of health data. William has been interviewed widely for his thought leadership, including in such leading publications as the international New York Times, Financial Times and The Guardian and writes for a number of publications including Thomson Reuters, Law360 and Global Data Review.