Dr. Fritz Lahrtz

Dr. Fritz Lahrtz

Patent Attorney
European Patent Attorney

  • Sectors

    Chemistry, Biology
  • Languages

    German, English, French, Portuguese
  • Location


Fritz Lahrtz represents his clients in all fields of intellectual property with an emphasis on patent prosecution and opposition, nullity and infringement proceedings. Specifically, in recent years, he has gained extensive experience in multinational infringement proceedings, where he represents his clients before the German Federal Patent Court, the German infringement courts as well as before the opposition divisions and appeal boards of the European Patent Office.

Since he is also responsible for establishing and coordinating the patent strategy of large patent portfolios, he has developed a deep insight into in all aspects of patent prosecution. This includes also the provision of validity and infringement opinions.

His clients include start-up companies, universities as well as large multinational companies. Due to his scientific education in the fields of immunology and neurobiology, he primarily works in the technical fields of biotechnology, chemistry and pharma, with an emphasis on handling antibody-related cases.

After having been trained as a German and European Patent Attorney in a renowned Hamburg based patent law firm, he worked as an associate in a well-known Munich based patent law firm. Fritz Lahrtz has been a partner at Isenbruck Bösl Hörschler LLP since the foundation of the firm in 2003.

He is the author several articles in the field of patent law as well as scientific publications.


  • European Patent Attorney
  • German Patent Attorney
  • European Trademark and Design Attorney
  • Degree of Dr. rer. nat.: Thesis on Cell Biology at the ETH Zürich
  • Degree of Dipl. Natw.: Thesis in the fields of Biochemistry/Molecular Biology at the ETH Swiss Federal Institute of Technology Zürich


  • epi Institute of Professional Representatives before the European Patent Office
  • FICPI International Federation of Intellectual Property Attorneys
  • Patentanwaltskammer (Chamber of Patent Attorneys)
  • VPP Association of Intellectual Property Experts
  • Union-ip Union of European Practitioners in Intellectual Property
  • ETH Alumni


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    Genetic Engineering
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    Molecular Biology
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    Organic Chemistry
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„Successful Strategies for the Patenting of Therapeutic Antibodies“, Journal of Biomolecular Screening , Bd. 20 (4), Official Journal of the Society for Laboratory Automation and Screening


„Pitfalls and Opportunities in Biotech and Pharma Patenting“, Co-Autor: H. Wichmann, Managing Intellectual Property, Bd. 4