About the Firm & the Founder

Zeitoune Janzen is a boutique law firm specializing in International Business Law

It was initially founded in 2000 in Hamburg, Germany, by Marcia Zeitoune Janzen, LL.M. Since then, the firm has served middle-sized companies, global conglomerates, and individuals on the bridge between Brazil and Germany. The firm partnered with major German law offices, opening Brazilian Desks in their international departments until the founder moved from Hamburg to Tel Aviv.

With a new office in Israel, the firm continues to exist in Germany in partnership with Clayston Law, which has offices in Hamburg, Berlin, Frankfurt, Zürich, Beijing, São Paulo, and Dubai.

In addition, Clayston has built a network of lawyers, medical advisers, auditors, and tax and business consultants in several European and Asian countries. 

In Israel, the firm added top-tier Israeli law firms and companies to its clientele. In addition, the firm’s connections with lawyers of different nationalities and law firms of different specializations and sizes allows it to work with the most appropriate professionals for the needs of its clients.

The clients operate in the Energy (Oil and Gas), Ports, Printing and Graphic, Chemicals, High Tech, AgriTech, Insurance, Foreign Trade, Aviation, Satellites and Mobile Telephony industries, among others.

The firm takes the needs of its clients very individually,
focusing on quality, not quantity.

Marcia Zeitoune Janzen, LL.M.

Marcia Zeitoune Janzen, LL.M. was born in Rio de Janeiro and spent 30 years of her professional life in Germany. In 2016 she moved to Israel, where she has studied Israeli law. 

Marcia graduated her law studies summa cum laude at the prestigious Rio de Janeiro State University and was admitted to the Brazilian Bar. She then received her Masters of Comparative Law at the University of Bonn, graduating magna cum laude. Marcia has been admitted in Brazil and Germany. In Israel, she will soon be admitted to the Israeli Bar.

Her extensive experience began in Brazil, in the financial contracts division of the legal department of the Chase Manhattan Bank, followed by activities with financial, commercial, and corporate agreements, as well as litigation in one of the best law firms in Rio de Janeiro. Later she moved to Germany on a grant and interned in the legal departments of the Deutsche Bank, Henkel, and a German Investments Bank.

After many years in the Dresdner Bank Lateinamerika, dealing with international compliance and financial contracts, she started her boutique law firm and subsequently headed Brazilian Desks in the international departments of Buse Heberer Fromm and Wülfing Zeuner Rechel.

Since 2016 in Tel Aviv, she continues working for her previous clients while advising top Israeli companies.



Portuguese, German, English, Spanish, French, Hebrew


Gläubigerschutz im brasilianischen und deutschen Aktien-Konzernrecht / Haftung der Muttergesellschaft für Verbindlichkeiten ihrer Tochtergesellschaft; Peter Lang Verlag. Frankfurt am Main, 1993, ISBN 978-3-631-43668-4 (Creditor’s Protection according to Brazilian and German Law – Liability of the Parent Company for Debts of its Subsidiaries)

Zur Rechtshilfe zwischen Brasilien und Deutschland – Gedanken und Vorschläge zur Verbesserung/ Sobre a Cooperação Judiciária entre Brasil e Alemanha – Ideias e Sugestões para melhoria (Ligiane Barnsteiner, Ana Elisa Bruder, Eduardo Caruso Cunha, Renata Curzel, Claudia Schallenmüller Ens, Andreas Grünewald, Volkhart Hanewald, Hans Jürgen Holweg, Marcia Zeitoune Janzen, Werner Müller, Beat W. Rechsteiner, Christof Schneider) ISSN: 2195-1438 (Print) ISSN: 2195-1446 (Internet) (Legal assistance between Brazil and Germany – ideas and suggestions for improvement)

Mehr Schutz für Minderheits- und Vorzugsaktionäre: Änderungen im brasilianischen Aktiengesetz in Sicht; in “Länderanalyse Brasilien” vom F.A.Z.-Institut für Management, Markt und Medieninformationen GmbH, Juli 2000, 25 ff. (More Protection for Minority and Preferred Stockholders: Alterations in the Brazilian Stocks Companies Law)

Zahlung und Überweisung von Royalties zwischen verbundenen Unternehmen nach Brasilianischem Recht; in “Mitteilungen” der Deutsch-Brasilianischen Juristenvereinigung e.V., 2/1987 (Payment and Transfer of Royalites within a Conglomerate under Brazilian Law)


Abertura de Empresas em Germany (Establishment of Subsidiaries in Germany)
Rio de Janeiro, 03.14.2011, Presentation together with the HWF – Hamburg Business Development Company

Unternehmenspartnerschaften in Brasilien (Partnership between Companies in Brazil)
Chamber of Commerce Hamburg, 11.06.2012
Presented in the Conference “Suppliers for the Maritime and Offshore Industry in Brazil”, in the Program of Market Entry of the Ministry of Economy and Energy

Abertura de Empresas em Hamburgo para empresários brasileiros (Establishing a Subsidiary in Hamburg for Brazilian Entrepreneurs)
EZLA Hamburg, 12.03.2014
Presented with HWF – Hamburg Business Development Corporation and EZLA – Europäisches Zentrum für Lateinamerika (European Center for Latin America), with Claudia Trinidad and Valentin Brauna