Defeng Song

Defeng Song
Partner at Fieldfisher. | China
Defeng Song is a Partner in Fieldfisher. He is a licensed attorney in China and the State of
New York and he also hold the qualifications of the PRC patent bar and US patent bar. He is
also, CIPP certified data practitioner in the United States.
Mr. Song practices intellectual property and technology law, mostly patent matters, but also
soft IPs, data protection, dispute resolution, etc. Mr. Song has rich experience in advising
clients’ patent contentious matters, including patent invalidation, patent infringement,
declaratory judgment action, patent ownership dispute resolution and inventorship dispute and
so on.
Mr. Song is familiar with the legal regimes of both China and the United States and helps
clients with both inbound and outbound business. He is often capable of analyzing legal issues
from a cross-jurisdiction perspective, by drawing on his knowledge in one jurisdiction in
solving problems in another.
Mr. Song is a regular writer of legal articles and has up to now written and published over 50
articles, mostly about significant cases and legislation in China and the United States, quote
often given from a comparative angle.