Supreme Court decision 2017Hu1304 has established an inherency doctrine in determining novelty. According to the decision, it is not enough to simply show the possibility or probability that something can be done to show prior art to be the same as the present invention; instead, it is necessary to show that it is an inevitable or a natural result. The purpose of the novelty requirement is important when judging novelty based on inherency. Theory of public domain, according to which patents are not granted for the subject matter already enjoyed by the public, is likely to play a greater role than theory of technical idea identicality, according to which patents are not granted for identical inventions. Therefore, in cases where a product or method already exists in prior art, meaning the public is already enjoying the benefits of using that disclosed product or method, novelty cannot be acknowledged simply by discovering the properties or characteristics of the recognized product or method. However, whether some products or methods are known in advance and thus the public are enjoying the benefits should be determined is very difficult to be determined, but it must be decided accurately through judgment as to whether the property or characteristic is an inevitable or natural result of the prior literature.