Andreas Lenz

Antonio Calderón is a top attorney recognized by Best Lawyers in the practice area(s) of Mergers and Acquisitions Law. Antonio, who practices law in Düsseldorf, Germany, has been recognized since 2025. This recognition is based on an exhaustive peer-review survey, reflecting the high esteem in which Antonio is held by other top lawyers in the same geographic and legal practice area.

Simon Groneberg is a top attorney recognized by Best Lawyers in the practice area(s) of Energy Law. Simon, who practices law in Düsseldorf, Germany, has been recognized since 2026. This recognition is based on an exhaustive peer-review survey, reflecting the high esteem in which Simon is held by other top lawyers in the same geographic and legal practice area.

Ingo Klauß is a top attorney recognized by Best Lawyers in the practice area(s) of Competition / Antitrust Law. Ingo, who practices law in Düsseldorf, Germany, has been recognized since 2022. This recognition is based on an exhaustive peer-review survey, reflecting the high esteem in which Ingo is held by other top lawyers in the same geographic and legal practice area.

Lawyer and Mediator Partner

Claudia Maaßen LL.M. is a lawyer and partner at Friedrich Graf von Westphalen & Partner. She has been working in the litigation and arbitration practice group of Friedrich Graf von Westphalen’s Cologne office since 2016. Claudia Maaßen is a specialist in dispute resolution with a focus on manager liability and D&O and product liability. Her clients include insurance companies, managers and private companies. Claudia Maaßen speaks German, French and English.

Legal studies at Bielefeld University State bar exam in 1984 Research associate under Prof. Dr. Westermann and Prof. Dr. Otte (Chairs for Civil Law) at Bielefeld University, 1984 - 1986 Bar admission in 1986 Doctor of Laws (Dr. jur.) 1987 Lawyer at the Hamm and Celle Higher District Courts, 1986 - 1989 With the firm since 1989 Certified Specialized Attorney in Tenancy and Condominium Law

Anja Commandeur is a top attorney recognized by Best Lawyers in the practice area(s) of Restructuring and Insolvency Law. Anja, who practices law in Cologne, Germany, has been recognized since 2021. This recognition is based on an exhaustive peer-review survey, reflecting the high esteem in which Anja is held by other top lawyers in the same geographic and legal practice area.

André-M. Szesny is a top attorney recognized by Best Lawyers in the practice area(s) of Criminal Defense and Criminal Tax Practice. André-M., who practices law in Düsseldorf, Germany, has been recognized since 2021. This recognition is based on an exhaustive peer-review survey, reflecting the high esteem in which André-M. is held by other top lawyers in the same geographic and legal practice area.

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

Jörn Zons is a lawyer and partner at Friedrich Graf von Westphalen & Partner in Cologne. Jörn’s main focus lies on German and international construction and engineering projects as well as domestic and international dispute resolution in litigation, arbitration and alternative dispute resolution proceedings. He is also a regular referee on German and international construction and engineering projects and dispute resolution at seminars, associations and in-house for compan...