Jacqueline Burckhardt Bertossa

Partner Dirk Spacek is partner and in charge of the practice groups TMC and IP. He primarily deals with new business models arising in the media-, internet- and technology(IT)-sector, data protection and intellectual property law. Dirk Spacek mainly advises clients from the media, technology, industry and financial services sectors on technology-related legal matters, in particular IT-contract law, outsourcing, data protection, Internet of Things (IoT), patent research and compatibility coope...

Olivier Sigg is a partner in the Private Clients team as well as an experienced employment lawyer. He heads our Geneva office. He is known, both in Geneva and in London, where he worked for one year, as an expert in complex crossborder matters and is regularly instructed by foreign lawyers, in particular from common law jurisdictions. Olivier Sigg’s private client practice includes various estate-planning techniques. In particular, as a TEP expert, he specialises in trusts, foundations,...

Partner Philipp Dickenmann is the head of the Dispute Resolution Practice Group of CMS Zurich. He also serves as core team member of the global CMS Dispute Resolution Practice Area Group as well as the CMS Commercial Practice Area Group. Philipp Dickenmann has extensive experience in commercial litigation and international arbitration. He acts as counsel and co-counsel, sole arbitrator and co-arbitrator in numerous national and international cases. This includes arbitrations conducted under t...

Partner Stephan Werlen focuses on M&A and corporate law, joint ventures, MBOs, acquisition finance, venture capital transactions, corporate restructuring and corporate relocation. He has broad experience both in domestic and international mergers and acquisitions (including auction processes) and the financing of such transactions. In addition, he is an expert in W&I insurance transactions (M&A insurance) with a long track record in this area. Stephan Werlen also regularly advises...

Robert Desax is a partner in the tax team. He works in the fields of national and international taxation. He represents clients in controversial tax matters and assists private clients regarding the tax aspects of estate and wealth planning. He regularly advises on cross-border implications of international taxation, especially on the application of double tax treaties, on issues in connection with the refund of Swiss withholding taxes in international structures, on the Swiss tax treatment o...

Partner Reto Hunsperger acts as head of the insolvency and restructuring department at CMS Zurich.He specialises in litigation and arbitration. With this focus, he represents national and international companies and individuals before state courts and arbitral tribunals (under ICC Rules, Swiss Rules and CAS Rules), mainly in civil, enforcement and sport law matters. In addition, he serves as an arbitrator. A further focus of Reto Hunsperger lies in all sorts of domestic and international inso...

Julien Witzig is a top attorney recognized by Best Lawyers in the practice area(s) of Tax Law. Julien, who practices law in Geneva, Switzerland, has been recognized since 2024. This recognition is based on an exhaustive peer-review survey, reflecting the high esteem in which Julien is held by other top lawyers in the same geographic and legal practice area.

Hans-Jakob Diem is a corporate Partner at Lenz & Staehelin. He heads the firm's Corporate and M&A practice group and is the co-head of the Capital Markets practice group in Zurich. He has extensive experience in representing clients in a variety of corporate transactions, concentrating on mergers and acquisitions, capital market transactions, bank financings and corporate governance matters. Hans-Jakob Diem is regarded as a leading corporate practitioner in Switzerland and is regularl...

Nicolas Béguin is a top attorney recognized by Best Lawyers in the practice area(s) of Banking and Finance Law. Nicolas, who practices law in Geneva, Switzerland, has been recognized since 2025. This recognition is based on an exhaustive peer-review survey, reflecting the high esteem in which Nicolas is held by other top lawyers in the same geographic and legal practice area.

Vaïk Müller is a top attorney recognized by Best Lawyers in the practice area(s) of Banking and Finance Law and Corporate Law. Vaïk, who practices law in Geneva, Switzerland, has been recognized since 2024. This recognition is based on an exhaustive peer-review survey, reflecting the high esteem in which Vaïk is held by other top lawyers in the same geographic and legal practice area.