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Beijing, Tokyo

The firm

Founded in Japan in 1910, Sonderhoff & Einsel Law and Patent Office has operated for more than 100 years in Japan as a leading firm with strong European ties. Having traditionally been among the first for German corporate clients seeking legal support in Japan, the firm presently assists a wide range of clients, not only from Japan but also from Europe, the US and China. In particular, recognising the growing importance of China for its clients, Sonderhoff & Einsel Law and Patent Office works in close collaboration with Sonderhoff & Einsel (Beijing) Patent Agency Office, which was founded in 2012.

Today, the firm offers 12 attorneys at law, with qualifications from Japan, the US and Germany, and 25 patent attorneys, supported by an in-house team of paralegals, technical specialists and translators. Its European roots are still evident under the leadership of patent attorney Felix-Reinhard Einsel, managing partner of the firm and the only European licensed as a patent attorney in Japan. Sonderhoff & Einsel’s legal practice has recently been strengthened by the addition of Keiji Isaji, who has focused his practice on litigation, finance and regulatory affairs during the more than 30 years of his career, and has since added eight attorneys at law with broad private experience at US and UK-based global firms as well as in-house experience at large international companies. Sonderhoff & Einsel is a full-service law firm with a particular strength in intellectual property law.

Areas of practice

With a 107-year history, the firm offers an outstanding comprehensive service to international clients. Emphasis is on all aspects of intellectual property law, including patents, utility models, designs, trade marks and unfair competition. The firm is also well-versed in global transactions with experience in a wide range of practice areas, such as general corporate and commercial transactions, mergers and acquisitions, labour and employment, finance, aviation and dispute resolution.

One of the competencies of its intellectual property practice is its reliable prosecution of patents covering a wide range of technology in the areas of mechanical engineering, electrical engineering and chemistry. For non-Japanese applicants, translations of patent applications into Japanese can be provided from English, German and Chinese, among other languages.

In its IP enforcement practice, Sonderhoff & Einsel counsels have developed a distinctive, cost-effective anti-counterfeiting practice that makes it a leading firm in the country. Certain patent cases handled by Sonderhoff & Einsel have become cornerstone cases in the field.

ContactsMr Felix-Reinhard Einsel, patent attorney
Mr Keiji Isaji, attorney at law


Other offices Beijing

German Chamber of Commerce and Industry in Japan
Swiss Chamber of Commerce and Industry in Japan
German Japanese Lawyers’ Association

Number of lawyers 12

Number of patent attorneys 25

Above material supplied by Sonderhoff & Einsel Law and Patent Office.

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