legal ground
Article 7 of the Measures for the Registration of Computer Software Copyright
The software applied for registration should be independently developed, or the original software is modified with the permission of the original copyright owner, which has a significant improvement in function or performance.
Article 9
To apply for software copyright registration, the following materials shall be submitted to China Copyright Protection Center:
(1) An application form for registration of software copyright that meets the requirements;
(2) Identification materials of the software;
(3) Relevant supporting documents.
Article 10
Software certification materials include certification materials of programs and documents.
The identification materials of programs and files shall consist of 30 consecutive pages before and after the source program and any kind of files. If the whole program and document are less than 60 pages, the whole source program and document should be submitted. Except in special circumstances, the program has no less than 50 lines per page and the document has no less than 30 lines per page.