Claudia Keller

Partner & Member of the Steering Committee of the CMS Competition & EU Group Marquard Christen specializes in competition (antitrust) and public procurement law. Marquard advises Swiss and foreign companies on all aspects of Swiss and EU competition law (horizontal and vertical agreements, dominance abuse, merger control and civil antitrust law) and represents them in proceedings before competition authorities and courts. Over the past 15 years, he has gained special knowledge in vari...

Manuel Bigler is a managing associate in the firms’ practice area Intellectual Property (IP). He advises and represents clients in all aspects of IP law with a particular focus on trademark, patent and copyright law. His practice also includes unfair competition, media and advertising law. He regularly advises clients in negotiating IP and technology-related agreements, such as license agreements. Manuel Bigler is further specialized in representing clients in disputes before courts and...

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...

Stefan Brunnschweiler is the managing partner of CMS Switzerland and co-heads the CMS Corporate/M&A Practice Area Group. He was named one of the top 10 lawyers in Switzerland in the edition of “Who is Who” by Bilanz. Stefan Brunnschweiler specialises in international and domestic M&A transactions, venture capital, corporate restructurings, corporate law and general contract matters (e.g. joint ventures, partnerships and shareholders' agreements). He is experienced in a bro...

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...

Irène Suter-Sieber is a top attorney recognized by Best Lawyers in the practice area(s) of Labor and Employment Law. Irène, who practices law in Zürich, Switzerland, has been recognized since 2026. This recognition is based on an exhaustive peer-review survey, reflecting the high esteem in which Irène is held by other top lawyers in the same geographic and legal practice area.

Luc Defferrard, partner with Walder Wyss since 2001, has been active in the finance and legal industry for many years. He mainly advises clients in domestic and cross-border mergers & acquisitions, financing, restructuring as well as in real estate and capital market. Luc Defferrard particularly focuses on private equity and venture capital transactions. He is regularly recommended by Chambers, Legal500 and IFLR1000. Chambers Europe describes him as "always available" and "very strong neg...

Markus Pfenninger is a partner in the Transactions Team. His fields of expertise include capital market transactions, mergers & acquisitions, finance, restructurings, collective investment schemes as well as banking and insurance regulatory matters. He is a member of the International Bar Association’s (IBA) Task Force on the Financial Crisis and a past chair of the IBA’s Subcommittee on Legal Opinions as well as a past co-chair of the IBA’s Banking Law Committee. Born i...

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

As Chief Executive Officer, Christian Lyk is responsible for the operational management of KENDRIS and also holds the position of Responsible Officer FATCA. He has extensive experience in regulatory and compliance matters and specialises in providing cross-border financial, tax, estate planning and family office services to ultra-high net worth individuals (UHNWIs). Christian Lyk began his career in a law firm before joining one of the Big 4 where he held a managerial position in the field of...