Nan Li formerly served as a director in multiple departments in State Intellectual Property Office (SIPO) for more than 10 years, and was appointed as one of the first batch of technical experts of the Beijing Municipal Intellectual Property Office, as well as one of the first batch of People's Jurors (Expert Juror) of the Beijing Intellectual Property Court.

Nan Li had worked with SIPO’s Patent Examination Cooperation Beijing Center since 2005. She focused on patent examination in the fields of Internet, IT hardware and software, e-commerce, telecommunication, network communication, blockchain, artificial intelligence, big data, medical devices, and high-end manufacturing. As the director of the Quality Control Office, she was responsible for conducting quality reviews, analyzing complex cases, unifying examination standards and handling public responses to major complaints. While at the Patent Service Department, she was in charge of overall management of patent service projects, and spearheaded collaborations with enterprises, universities and local intellectual property offices. She participated in a broad range of national-level projects such as “Internet of Things Industry Innovation” with Guangdong Province, and "R&D and Intellectual Property Issues concerning Standard Bullet Trains", etc.

As a technical expert juror and a technical expert at Beijing Intellectual Property Court and Beijing Municipal Intellectual Property Office, Nan Lis participated in a number of patent litigation and administrative enforcement proceedings including some high profile cases such as Apple Inc. v. Shanghai Zhisheng Co. (involving "Siri" technology), Huawei v. ZTE , Jinyun Co. v. Mobike Inc. ( shared bicycle technology), and Celgene v. SIPO (post-filing data submission ) .

Nan Li was selected by SIPO as an instructor for patent attorney training programs and was responsible for developing courses concerning patent infringement matters. She was also in charge of the training courses for patent attorneys concerning patent application drafting in the electrical field, training courses for new examiners at the Beijing Center of Patent Examination Cooperation, training courses concerning medical device patents for Food and Drug Administration, and patent courses at Tsinghua University, etc.

Nan Li has co-authored books of “Commentary on Invention Patent Subject Matter Reviews” and “Patent Search Strategy”, and also published 10 journal papers.