China: CNIPA and courts open door to post-filing supplementary data Li Wu of AnJie Law Firm explains how the administrative and judicial sectors are slowly embracing a more favourable stance towards the acceptance of post-filing supplementary data Sponsored by February 23 2021 China had long been criticised for adopting much stricter criteria for post-filing supplementary data in the pharmaceutical field than other major patent systems. The issue was even discussed as one of the main topics of the US-China trade talks and was listed in the US-China trade deal entered into in January 2020. As a result of this, a great number of Patent Cooperation Treaty (PCT) applications entering into Chinese national stage have been deemed as not patentable due to the lack of experimental data, either in the prosecution stage or in the post-grant proceedings. Recently, however, there are signs indicating that the tide may be changing.