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Lenz & Staehelin

Work +41 58 450 80 00
Fax +41 58 450 80 01
Geneva, Lausanne, Zurich

Hans-Jakob Diem

Work +41 58 450 80 00
Lenz & Staehelin

Work Department

Corporate and Mergers & Acquisitions, Capital Markets, Corporate Governance, Banking and Finance.


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 regularly involved in high-profile transactions in the Swiss market, both domestic and cross-border. He also serves as principal outside counsel for a number of clients on stock exchange and securities trading law and corporate governance matters.

Besides his corporate practice, Hans-Jakob Diem lectures corporate and
M&A law at the universities of Basel and Zurich and is a regular speaker at conferences, an author of various legal textbooks and a regular contributor in law journals.


Admission to Basel Bar (1995), Associate at Lenz & Staehelin (1998), Partner at Lenz & Staehelin (2007).


German, English, French.


Zurich Bar Association (ZAV), Swiss Bar Association (SAV), International Bar Association (IBA), Swiss Private Equity & Corporate Finance Association (SECA), Swiss-American Chamber of Commerce, Swiss-Chinese Chamber of Commerce (SCCC), Swiss Institute of Directors, Swiss LSE Alumni Association, admitted as an expert to the SIX Swiss Exchange for

Listing Purposes.


University of Basel (lic. iur. 1992), London School of Economics and Political Science STET (LL.M. 1998).


Capital markets

Within: Capital markets

One of the 'leading practices in Switzerland', Lenz & Staehelin's 'depth and quality is world class'. Equity transactions, bond offerings, securitisation, derivatives, convertibles and structured notes are among its areas of expertise. 'Stand-out performerJacques Iffland advised ObsEva on a $60m private investment of shares and short-term warrants regarding a public equity transaction with several investors, while Rudolf Tschäni and Hans-Jakob Diem assisted Sika with its CHF1.65bn issuance of senior convertible bonds on SIX Swiss Exchange. 'Knowledgeable and thorough' derivatives and structured products expert François Rayroux and Zurich co-lead Patrick Schleiffer are other names to note.

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Commercial, corporate and M&A

Within: Leading individuals

Hans-Jakob Diem - Lenz & Staehelin

Within: Commercial, corporate and M&A

Lenz & Staehelin's 'highly recommended, hands-on' team stands out for its 'very thorough levels of preparation' and 'impeccable integrity', 'combining exceptional lawyers with tremendous collegiality and client service'. Focus areas include private and public M&A, corporate governance, and private equity transactions. In a recent highlight, 'world-class M&A lawyerHans-Jakob Diem assisted Saudi Basic Industries with its upcoming 24.99% share capital acquisition in Clariant. Rudolf Tschäni is another key practitioner, while clients further recommend 'extraordinarily smartTino Gaberthüel; 'committedBeat Kühni, who has 'an encyclopaedic knowledge'; 'clear, proactive and quickStephan Erni; as well as 'efficient and flexible' Geneva-based Guy Vermeil.

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Leading firms: German-speaking Switzerland

Within: Leading firms: German-speaking Switzerland

Lenz & Staehelin has supreme experience of banking and finance, capital markets, corporate and M&A, competition and dispute resolution, with additional expertise in IP, TMT, sports and tax matters. Patrick Hünerwadel, Marcel TranchetHans-Jakob Diem, Harold Frey, Marcel Meinhardt, Jürg Simon and Lukas Morscher are among the leading individuals.

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Switzerland: Mergers & Acquisitions (3rd edition)

This country-specific Q&A provides an overview to M&A laws and regulations that may occur in Switzerland . This Q&A is part of the global guide to Mergers & Acquisitions. [Continue Reading]

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