The "Patent Examination Guidelines" point out that an invention has outstanding substantive features, which means that to a person skilled in the technical field, the invention is non-obvious compared to the existing technology. If an invention can be obtained by a person skilled in the technical field only through logical analysis, reasoning or limited experiments on the basis of the existing technology, then the invention is obvious and does not have outstanding substantive features. The Patent Cooperation Treaty International Search and Preliminary Examination Guidelines stipulate that obviousness does not go beyond the normal development process of technology, but is simply or logically obtained from the existing technology, that is, it does not include skills beyond the expected technical field. any practical skills or abilities.
However, not all inventions obtained through logical analysis, reasoning or experiments on the basis of existing technologies are obvious. It is easy for parties to conduct post hoc analysis based on reading application documents and commit "post hoc" Zhuge Liang's mistake, therefore, we cannot simply use "can be obtained through logical analysis, reasoning or limited experiments" to arbitrarily conclude that the invention is obvious.