Andreas Oser

Managing Partner at Prüfer & Partner
Ranked in Germany
IAM Research

The Patent 1000 focuses exclusively on patent practice and has firmly established itself as the definitive 'go-to' resource for those seeking world-class legal patent expertise.

Recommended - Individuals: prosecution and nullity

“Prüfer & Partner is excellent. Its responses are always very quick and appropriate, and its ability to understand and analyse legal and technical issues is high. Japanese clients in particular are totally satisfied with the quality and cost-effectiveness of the work provided by the firm.” “The firm understands what clients need, not just in terms of patent knowledge but also commercial guidance throughout the process. The technical background is there, the staff are friendly and to the point, and even with international issues there is no need to go to anyone else.” With feedback of this calibre, it should be no surprise that Prüfer & Partner has continued to thrive in the German patent prosecution space. It offers the full suite of services to clients, including printing leader Brother, which has had its patent filings handled by managing partner Jürgen Feldmeier over the past year. Having been involved in more than 100 contentious proceedings over his career, Feldmeier knows all there is to know about European patent law, and has the reviews to show for it: “Mr Feldmeier has a strong ability to understand complicated technical matters, provides astute advice and deals with matters with the appropriate urgency.” His fellow managing partners are Dorothea Hofer and Andreas Oser. Hofer has lately been handling an expansive cross-border mandate on behalf of EOS GmbH Electro Optical Systems and EOS of North America, filing an entire family of patents and defending them in ongoing oppositions, while Oser is a medical devices and pharmaceuticals maven, who has recently been advising new patron B Braun Melsungen on infringement and freedom-to-operate questions.

Andreas Oser's Profile

Andreas Oser has been working in the IP field since 1991; he became a German and European patent attorney in 1995 and has been managing partner at Prüfer & Partner since 2002.

Prior to working in intellectual property, he studied chemistry at the University of Freiburg in Breisgau, and then conducted his PhD and postdoc studies at the Max Planck Institute for Biochemistry in Munich. He also holds an LLM degree in international IP laws from the University of Hagen.

Dr Oser’s primary areas of expertise are chemistry, pharmaceuticals, life sciences and biotechnology – in particular, biological materials, DNA-related inventions and vaccines; therapeutic and diagnostic methods; medical products and devices, and targeted drug delivery; polymers and fibre materials; semiconductors, LEDs, OLEDs and other optical materials and optoelectronic devices; and batteries and their components.

His activities include patent prosecution (drafting, examination); a 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 analyses; and due diligence.

Dr Oser is heavily involved in numerous litigation cases, among others related to medical devices and important drug products.

Firm Profile

Prüfer & Partner is one of the most renowned IP specialist law firms in Germany. At Prüfer & Partner, we take care of the protection of ideas, inventions and product developments worldwide and enforce our clients’ claims in court – regardless of whether it is a matter of enforcing technical inventions or other types of property rights or IP rights.

Prüfer & Partner is an IP boutique offering a full range of IP services. Founded in 1972, Prüfer & Partner underwent a successful generational change between 1998 and 2002, when it was taken over by patent attorneys Dorothea Hofer, Jürgen Feldmeier and Andreas Oser. With the addition of attorney Andreas Jacob to the partnership in 2015, the firm has also been able to significantly expand its existing expertise in patent litigation and attorney services.

With Prüfer & Partner, you can expect a strong and carefully selected community of patent attorneys, lawyers and technical specialists. Regular audits ensure that we meet our high-quality standards, which we set for ourselves. This enables us to offer our clients representation of interests at the highest level at any time and in any situation. We handle complex and demanding mandates with the highest level of commitment in individually assembled teams of experts, as we attach great importance to thoroughness, time and cost efficiency.

Over the past decade, Prüfer & Partner has continuously expanded its expertise in patent and trademark litigation. Dr Hofer and Mr Feldmeier have been advising BROTHER Industries for several years in a complex patent dispute concerning ink cartridges. Dr Oser supports the pharmaceutical industry, such as parts of the Novartis Group in building up their patent portfolio as well as with litigation. Mr Jacob is active in both patent and trademark proceedings before the courts in Germany, but also supports his clients in international disputes, especially in China-related cases. Other attorneys at the firm, such as Christian Einsel, also routinely handle patent cases on behalf of both plaintiffs and defendants. Christian Gärtner also handles many opposition and appeal proceedings before the European Patent Office and the German Patent and Trademark Office. In addition, Marion Ziliox acts for French and Asian clients, among others, in customs actions at the borders of the European Union. This illustrates Prüfer & Partner’s profound expertise across the entire IP area.

In addition, Prüfer & Partner has a well-established desk in China and continuously cultivates its business in China and other Asian countries – in particular Japan.

Looking to the future, Prüfer & Partner plans to both consolidate and broaden its activities in Germany to serve German and European clients, especially small and medium-sized enterprises and start-ups, helping them protect their innovations and strengthen their position in an increasingly competitive market.

Located in Munich, the German heart of intellectual property, Prüfer & Partner is dedicated to serving its clients as a one-stop-shop IP boutique.

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