David Rosenthal
Team Head / Partner
David Rosenthal is one of the leading Swiss experts in the field of Data and Technology law. His background is atypical: he graduated in law at the University of Basel in 1997 and worked as a software developer, legal advisor and journalist before joining one of Switzerland’s top law firms, where he built up and managed the data protection department, among other things. In addition to data law (including GDPR) he advises on AI, projects in the IT, cloud and digital business sector and represents clients in technology-related arbitration proceedings. His clients include major international corporations as well as Swiss SMEs, start-ups and public authorities; he is regarded as pragmatic, efficient and solution-oriented, and has a deep technical understanding. Rosenthal also has over 15 years of experience in conducting internal investigations and cross-border e-Discovery projects. He is Secretary of the Association for Corporate Data Protection (VUD) and the Cross- border eDiscovery Privacy & Investigations Association (CeDIV), as well as lecturer at the ETH Zurich and the University of Basel. Rosenthal is not only active as a lawyer: He has also developed several AI tools and heads the VISCHER Legal Innovation Lab.
"I appreciate David Rosenthal's broad cross-domain expertise in IT, data protection law and business. He thinks in an interconnected way across all three domains and is clearly the best data protection expert in Switzerland."
Legal 500 - 2026
"David Rosenthal and Samira Studer are among the standouts, and we work regularly with them."
Legal 500 - 2026
"David Rosenthal and Elias Mühlemann are very intelligent persons, offering strategic thinking, adept at rhetorical fights in negotiations, deeply informed about all the psychological and legal possibilities in discussions."
Legal 500 - 2026
"David Rosenthal is an undisputed leader in data protection and related fields. He is well connected with stakeholders and authorities, develops compliance tools beyond legal advice and manages a team of talented individual."
Legal 500 - 2026
"David Rosenthal's team is one of the best in Europe. Always ahead of the curve, lovers of legaltech. Their advice is precise and practical."
Legal 500 - 2026
"David Rosenthal understands the clients’ needs, listens and provides practical solutions. He comes up with unique ideas."
Legal 500 - 2026
"David Rosenthal is a luminary. Thanks to his training as an IT software developer, he's familiar with all facets of the field."
Legal 500 - 2026
"David Rosenthal is a very good lawyer with deep knowledge of AI law and tech. He has a very clear way of expressing himself; one understands what he is saying. "
Chambers and Partners - 2026
"He is the best in the field. "
Chambers and Partners - 2026
"He is a very sophisticated person, with very deep knowledge in rights and IT solutions. "
Chambers and Partners - 2026
"David provides clear and pragmatic recommendations, going beyond pure legal advice and also taking business aspects into consideration. He is very approachable and is available at short notice. "
Chambers and Partners - 2026
"David Rosenthal is one of the most exceptional lawyers I have encountered in my career. "
Chambers and Partners - 2026
"David Rosenthal is particularly noted for his strong expertise in data protection matters, including advising on responses to ransomware attacks. He also has notable experience in cloud migration matters, the introduction of new technology platforms, AI advice and telecommunications sector disputes. "
Chambers and Partners - 2026
"David Rosenthal is convincing in every respect. He has excellent expertise and experience and an excellent reputation within the industry."
Chambers and Partners - 2025
"David Rosenthal has outstanding expertise in data protection and technology law."
Chambers and Partners - 2025
"David Rosenthal is a very clever, interested and friendly lawyer. We love working with him."
Chambers and Partners - 2025
"David Rosenthal is excellent in his work and truly a market leader."
Chambers and Partners - 2025
"David Rosenthal is lightning fast, has excellent knowledge of the customer's real pain points and is in a position to shape standards and best practices."
Chambers and Partners - 2025
"I like the straightforward approach. The team around David is very approachable, you can always call and the advice helps in everyday business life. You feel well advised and are also made aware of new laws and regulations without getting the feeling that David and his team mainly want to sell hours, but want to help."
The Legal 500 - 2025
"David is not only an expert in legal matters but also in technical matters. This is extremely valuable, as there are very few lawyers who are familiar with both the technical and legal aspects."
The Legal 500 - 2025
"The primary reason for the firm's outstanding expertise in data protection is David Rosenthal. With his unique background in both technical and legal fields, combined with his extensive experience, he is regarded as one of the leading experts in data protection."
The Legal 500 - 2025
"David Rosenthal is one of the leading experts in this area in Switzerland, also with regards to AI."
The Legal 500 - 2025
"David Rosenthal is very present on all different fields of technology laws and provides a lot of material for free. He is not shy from taking sometimes an out-of-the-box view and come up with solutions for problems the competitors have not yet even identified."
The Legal 500 - 2025
"VISCHER has one of the largest and most prolific legal teams in data privacy. They are clear market leaders, spearheaded by superstar David Rosenthal. The team is experienced, business-oriented and very responsive."
The Legal 500 - 2025
"David Rosenthal is a household name in data privacy in Switzerland and the clear thought leader in this field. He is always ahead of the curve, uses the most innovative tools and is always available."
The Legal 500 - 2025
"David Rosenthal is exceptional, one of the best privacy lawyers I know. Super innovative and pragmatic."
The Legal 500 - 2025
"Recommended in Information Technology Law, Media Law, Technology Law, Telecommunications Law"
Best Lawyers Switzerland - 2024
"David Rosenthal is very knowledgeable in all matters involving data and is one of the opinion leaders in Switzerland."
Chambers and Partners - 2024
"David is incredibly fast. You get a helpful and well-rounded answer."
Chambers and Partners - 2024
"Highly recommended in Internal Investigations & Compliance"
Leaders League: Switzerland - Best Law Firms - 2024
"I have worked closely with David Rosenthal for years and appreciate his pragmatic approach. I know whenever I have a problem in the area of data protection, IT, technology, that I can rely on him there."
The Legal 500 - 2024
"The VISCHER privacy team around their lead David Rosenthal are among the best in Switzerland. They are extremely knowledgeable, creative and responsive."
The Legal 500 - 2024
"David Rosenthal is constantly innovating new tools or ways to assess risks."
The Legal 500 - 2024
"I am a HUGE fan of David and his team."
The Legal 500 - 2024
"David Rosenthal is not only a leading lawyer in Switzerland’s world of data protection, he also has expertise as a developer. On top of that, he willingly shares a lot of his know-how freely and makes it available to everybody. I think he is somebody who really tries to make the world a better place when it comes to data protection, and I admire this spirit."
The Legal 500 - 2024
"David Rosenthal is the number one opinion leader in data protection."
The Legal 500 - 2024
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Who's Who Legal Thought Leader - 2024
"David Rosenthal showed his profound know-how and competence in this section."
Chambers Europe - 2023
"‘David Rosenthal is the most prominent and active data privacy lawyer in Switzerland. He is the most prolific opinion leader in data privacy in Switzerland. Rolf Auf der Maur is very well connected and has in-depth knowledge of the media and tech industries. Michael Waldner is an expert in health law and has a brilliant mind.’"
Legal 500 - 2023
"‘David Rosenthal is a very pragmatic and solution oriented negotiator. We highly appreciated his work for us in negotiations with a big international cloud provider.’"
Legal 500 - 2023
"‘The VISCHER data privacy team has seen exceptional growth since David Rosenthal joined the firm. They are now one of the leading data privacy teams in Switzerland.’"
Legal 500 - 2023
"‘David Rosenthal is THE most prominent data privacy lawyer in Switzerland. David has a very business-oriented approach and always thinks out of the box to find practicable solutions. He also has an exceptionally large network both in Switzerland and abroad. David has become an opinion leader in data privacy on an international level. He developed a TIA tool that has become the standard for conducting transfer impact assessments not only in Switzerland but also internationally. He has often been referred to as “Mr. TIA”.’"
Legal 500 - 2023
"David Rosenthal is regarded as "the leading practitioner in his area" who is highly knowledgeable on data protection law and skilfully represents a range of clients in the technology sector."
Who's Who Legal - 2023
"David Rosenthal is praised by peers and clients alike for his "outstanding knowledge of forensic and e-discovery technology" and experience handling complex corporate investigations."
Who's Who Legal - 2023
"Recommended for Information Technoloigy Law, Media Law, Technology Law, Telecommunications Law"
Best Lawyers Switzerland - 2022
"David Rosenthal is particularly noted by sources for his strong expertise in data protection matters, including advising on responses to ransomware attacks. He also has notable experience in cloud migration matters, Internet of Things issues, the introduction of new technology platforms and telecommunications sector disputes. A commentator says: "He leads the field in understanding and measuring risk.""
Chambers Europe - 2022
"Leading in Data Protection and in IT & Outsourcing – 2022"
Leaders League: Switzerland – Best Law Firms - 2022
"David Rosenthal is a leader in the area of data protection. He has significant experience in the application of data protection implication in the litigation and investigation context. David Rosenthal provides valuable practical advice to navigate cooperations through the issue of cross-border transfers."
Legal 500 - 2022
"We had the great pleasure to work with David Rosenthal. In our experience, he is an absolutely brilliant mind, one of the leading data protection lawyers in Switzerland, fun to work with, the best you can get in Switzerland, goal-oriented and extremely efficient. Our experience with him is outstanding and exceptional in every respect."
Legal 500 - 2022
"David Rosenthal: An outstanding expert who is able to speak ‘normal’ language with the clients.’"
Legal 500 - 2022
"David Rosenthal possesses “a razor-sharp intellect” and “delivers legally astute advice which is very practical and understanding of business realities”."
Who's Who Legal - Data - 2022
"David Rosenthal is a “great lawyer”. He is “very knowledgeable” and is regarded as “a trendsetter in data privacy law”."
Who's Who Legal - Data Privacy & Protection - 2022
"David Rosenthal is particularly noted by sources for his strong expertise on data protection matters. He advises on a range of mandates, including cloud migration, data protection and IT contracts. Interviewees say he is "client-friendly and up-to-date.""
Chambers Europe - 2021
"VISCHER’s data privacy and data protection team advises companies on compliance matters relating to Swiss and EU data protection and data law requirements as well as the data-related aspects of commercial contracts and M&A transactions. The group has also seen an uptick in instructions to handle data protection-related disputes, including those related to data subject requests. David Rosenthal - an ‘expert in matters of data privacy and data protection’ - is at the forefront of developments in the industry and has been involved in the creation of a statistical method designed to assess the data law risks of foreign lawful access in cases of Swiss banks, hospitals and other operations with sensitive data held in the cloud. Rolf Auf der Maur advises companies primarily from the media, telecoms and IT sectors on all aspects of data law."
Legal 500 - 2021
"Key practice areas for VISCHER are capital markets, M&A, healthcare, TMT and transport as well as public law, competition and litigation. Among the names to note are Klaus Neff, Stefan Kohler, Rolf Auf Der Maur, Benedict Christ, David Rosenthal and Stefan Rechsteiner as well as Christian Oetiker, Michael Waldner, and Christian Wyss."
Legal 500 - 2021
"We mainly work with David Rosenthal and appreciate his uncomplicated way of working. He is very responsive and return calls are made on the same day. His recommendations have been applied to our business and therefore offer real added value."
Legal 500 - 2021
"David Rosenthal is hailed a 'pioneer of swiss data protection law' and is well respected for his encyclopaedic knowledge of the field."
Who's Who Legal - 2021
"“David Rosenthal is ‘absolutely stellar’ in data protection mandates, according to one client, while another enthuses: ‘He is very efficient, always fast and very straightforward’.”"
Chambers Europe - 2020
"“I work predominately with David Rosenthal. He is outstanding in that he is always reachable, reliable and ready to provide workable solutions on the spot. He has an outstanding ability to find creative solutions and never shies away from entering uncharted territory and be the pioneer on expressing a legal view. He is extremely easy to work with and his advice is always clear and on the point.” "Beyond his specific expertise in TMT which he can bring to our topic where needed (which is a greenfield topic, probably a 'frist'), he stands out with hands-on pragmatism in solving problems (vs. commenting on them).""
Legal 500 - 2020
"“David Rosenthal is a leading light in the data field who garners plaudits as “the most experienced data protection lawyer in Switzerland”. He draws praise for his contribution to related case law and legal doctrine.""
Who's Who Legal - 2020
"David Rosenthal is a leading light in the data field who garners plaudits as 'the most experienced data protection lawyer in Switzerland'. He draws praise for his contribution to related case law and legal doctrine."
Who's Who Legal - 2020
"Recommended for Data - Information Technology"
Who's Who Legal - 2020
"Independent practitioner David Rosenthal is renowned for his 'long-standing experience, both academically and as a practitioner' in the data space, spanning technology, e-discovery and data protection law."
Who's Who Legal - 2020