Recently, the National Intellectual Property Administration issued the Notice on Closing Windows for PCT International Application Files Submitted via Facsimile. 

Starting March 1st, 2023, the Chinese National Intellectual Property Administration will no longer accept PCT international application files submitted via fax or any related documents or letters submitted after the application. PCT international applicants can submit PCT international application files and handle related business to the Chinese administration through the "Patent Business Handling System" platform and web version (https://cponline.cnipa.gov.cn) either electronically or in paper form.