March 30, 2020, Shanghai High People’s Court (“SHPC”) dismissed the appeal of Sogou and ruled in the final judgement that the software “Baidu Input Method” does not infringe Sogou’s Patent No. ZL200810113984.9. The SHPC's holding on two key issues needs our attention:

[Allocation of burden of proof] In view that the measures to achieve certain function in software are often invisible,  the measures for achieving function in this case were inferred from the corresponding relationship between the phenomenon of software operation and the measures. It is necessary to reasonably allocate the parties’ burden of proof based on the capability of producing evidence and in this case the burden of proof was shifted according to the results of each party’s operation in tests.

[Protection of confidential information] Since this case involves the disclosure of software codes of Baidu Input Method, which is confidential, the court held that the hearing about the finding of confidential technical facts of Baidu Input Method not open to public including the engineers of Sogou. Only attorneys of both parties and third-party experts could attend the hearing related to such confidential information.