Patentanwälte Isenbruck Bösl Hörschler PartG mbB

IAM Research

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Patentanwälte Isenbruck Bösl Hörschler lands its first spot in the rankings this year as “a reliable group of professionals characterised by profound knowledge of patent issues and excellent strategic insight”. Its thriving EPO oppositions practice is in particularly hot demand among biotechnology and pharmaceutical multinationals. Many of these are catered to by the “outstanding” Fritz Lahrtz, who has been with the firm since its establishment in 2003; he is highlighted for his “tough but fair approach” and “remarkable technical expertise”. At his side are fellow pharmaceutical aces Stephanie Nottrott and Stefan Feaux de Lacroix. Nottrott’s post-doctoral achievements in the biochemical and molecular biology fields underpin the “deep scientific understanding” she displays in commercially crucial office actions. Founding partner Feaux de Lacroix holds a PhD in polymer chemistry; he not only acts in a broad range of EPO oppositions, but also provides valuable support in court litigation.

Firm Profile

Isenbruck Bösl Hörschler was established in 2003. As illustrated by its annual ranking in the most influential IP publications, the firm has established itself among the leading IP law firms in Germany. It is an IP-specialised firm that is large enough to have a strong attorney base, yet small enough to ensure that each client receives the attention and diligence it deserves.

The firm's extensive clientele includes major corporations within key industries and small to mid-size companies, as well as start-ups and universities – both in Germany and worldwide. Their clients appreciate "the extremely high level of commitment of all employees", as well as "the excellent advice regarding strategic issues" (Chambers Europe 2020).

Fields of practice

Isenbruck Bösl Hörschler is well versed in all aspects of the protection of intellectual property. The firm's patent attorneys advise their clients on the prosecution of technical and non-technical protective rights, as well as the defence and enforcement of patents (including supplementary protection certificates), utility models, trademarks and designs. They are dedicated to supporting their clients with drafting and negotiating technology-oriented contracts and licence or cooperation agreements. In addition, the firm assists clients in establishing and evaluating technology platforms and IP portfolios.

The firm provides full services for the protection of IP in all technical fields, in particular:

  • organic chemistry, catalysts, polymers, fire chemistry;
  • pharmaceuticals, diagnostics, vaccines, antibodies;
  • biotechnology, molecular biology, RNA technology;
  • apparatus, medical and diagnostic devices;
  • physics;
  • mechanical and electrical engineering; and
  • software and computer-implemented inventions.


An important aspect of the firm’s practice relates to defending or attacking European and German patents in opposition/invalidation and appeal proceedings before the EPO and the German courts. In cooperation with selected specialised litigators, Isenbruck Bösl Hörschler is continuously involved in infringement proceedings before German courts concerning patents and utility models, including cross-border litigation and nullity actions before the Federal Patent Court and the Federal Court of Justice.

Team experience

With 13 partners and 11 associates – all experienced scientists and engineers, as well as highly qualified patent attorneys – Isenbruck Bösl Hörschler is able to provide effective and innovative prosecution and litigation strategies. Their professional team is client-oriented, thorough, creative and legally sound in the counselling of all aspects of intellectual property. Languages spoken range from German, English and French to Dutch, Spanish, Italian, Portuguese and Chinese.

Many of the firm's patent attorneys play an active role in professional associations, serving on the board of the German Chamber of Patent Attorneys, the board of GRUR – the German Association for the Protection of Intellectual Property – and as members of the German Patent Attorneys' Bar Association Committee for Trademark Law, among others. In addition, one of their partners is a tutor at the Centre for International Intellectual Property Studies at the University of Strasbourg, and several associates support the Chambers of Trade and Crafts for Munich and Upper Bavaria, as well as Mannheim Rhein-Neckar-Odenwald, advising its members on inventions.

Local strength, global reach

With offices in Mannheim, Munich and Dusseldorf, Isenbruck Bösl Hörschler is at your service in the most important locations for IP rights in Germany. In cooperation with selected, highly qualified foreign associates, the firm provides comprehensive services worldwide.

Key clients

  • BASF
  • Roche Diagnostics
  • Robert Bosch
  • INEOS Styrolution
  • EuroChem Agro
  • Celanese
  • Clariant
  • Ascendis Pharma
  • cynora 
  • Chugai Pharmaceutical
  • G Pohl-Boskamp
  • Fujifilm Cellular Dynamics
  • Agenus
  • ImmunoGen
  • Fraunhofer-Gesellschaft
  • DKFZ
  • Merck 
  • ARLANXEO Deutschland
  • uniQure
  • c-LEcta

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