Dr. Andreas Oser, LL.M.

Dr. rer. nat., Dipl.-Chem.
German Patent Attorney, European Patent Attorney, European Trademark and Design Attorney
Master of Laws



  • chemistry, pharmaceuticals, life science and biotechnology, in particular:
  • medicaments and drugs, formulations, biopharmaceuticals 
  • biological materials, DNA-related inventions and vaccines
  • therapeutic and diagnostic methods
  • medical products & devices and targeted drug delivery
  • polymers and fibre materials, composites
  • semiconductors, LEDs, OLEDs and other optical materials and optoelectronic devices,
  • batteries and their components 

Patent prosecution (drafting, examination)
High number of opposition and appeal proceedings at the European Patent Office
Patent litigation: Patent infringement proceedings before German courts, nullity proceedings up to the highest instance, the Federal Supreme Court; also covering coordinated and complex EU-wide litigation activities  
Infringement and validity opinions, freedom-to-operate (FTO) analyses, due diligence

Andreas Oser was and is currently involved in many litigation cases, among others related to medical devices and important drug products.

Andreas Oser has been working in the IP field since 1991, became German and European patent attorney in 1995 and is managing partner at Prüfer & Partner since 2002.
In addition he holds an LL.M. degree in International Intellectual Property Laws (University of Hagen).
Prior to working in IP field, he studied chemistry at the University of Freiburg i. Brsg., and then made his Ph.D. and postdoc scientific work at the Max Planck Institute for Biochemistry in Munich.

Schmidt T. und Oser A., GRUR Int 2019, 737: "New medical uses of known medical devices – A new perspective on purpose-limited product protection for medical devices in Europe"
Oser A. in GRUR Int 1998, 648 (=IIC 30, 1-18, 1999): “Patenting (Partial-)Gene Sequences
Oser A., PATENTS & LICENSING 1998, 30: “EU Directive on Legal Protection of Biotech Inventions
Oser A. and Bavec S., AIPPI Japan 2004 (Vol. 49 No. 7), 503: “Biotech Inventions in Europe
Oser A. in GRUR Int 2006, 539 (=IIC 37, 520-550, 2006): “European Patent Litigation Agreement - Admissibility and Future of a Patent Dispute Regulation in Europe"
Thieme R„ Lay H., Oser A., Lehmann J., Wrissenberg S. and Boos W., Eur, J.Biochem. 160, 83-91 (1986)
Oser A., Roth W.K. and Valet G., Nucl. Acids Res. 16, 1181-1196 (1988)
Oser A. and Valet G., Nucl. Acids Res. 16, 8178 (1988)
Rothe G., Oser A. and Valet G., Naturwissenschaften 75, 354-355 (1988)
Oser A., Collasius M. and Valet G., Anal.Biochem. 191(2), 295-301 (1990)
Oser A. and Valet G., Angewandte Chemie International Edition 29(10), 1167-1169 (1990)
Rothe G., Banati R., Oser A., Assfalg-Machleidt I., Mangel W.F., Machleidt W., Kreutzberg G.W. and Valet G., Journal Immunol. Methods. 138(1), 133-135 (1991)  
Oser A. and Valet G. (1988), Patent Applications WO8907606A, DE3804243A

Chamber of Patent Attorneys
epi - European Patent Institute
Member of the Biotech Committee of the epi
AIPPI - International Association for the Protection of Intellectual Property
FICPI - International Federation of Intellectual Property Attorneys
LES - Licensing Executives Society
GDCh - Gesellschaft Deutscher Chemiker

English, German and French 


« back