To be patented, an invention must have industrial applicability, novelty, and non-obviousness. Industrial applicability in an invention can be found in almost any use in industrial fields, except purely academic formula or treatment method for human being. In some case, what does not constitute technical idea or what lacks practicality may receive a rejection under lacking the industrial applicability from the examiner for the reason that non-invention itself is not a ground for rejection. Making money or charging money can be patented in the recent business model trend.

Novelty in Japan concerns worldwide regions and even the world wide web. The Japanese patent law requires the absolute novelty for patents. That is, any use or publication of an invention even outside the territory of Japan may affect the patentability of the invention if the application for the invention is filed after the use. There are some exceptions of the novelty requirement: testing, publishing through periodicals or network, making a seminar with a document may be precluded from evidence to strike the patent. When the novelty was lost due to an incidence against will of the patentable right owner or displayed in some exhibition, such exceptions may be applicable.

Non-obviousness is generally the highest hurdle in patent acquiring race. Based on matters publicly known before the filing date, the subject matter of the patent application should be out of a scope that a person skilled in the art can easily conceive. The person skilled in the art is an objective human being, and the examiner takes the objective position to treat every patent fairly. In Japanese practice, the advantage of the invention is the key point to make distinction between non-obvious matter and obvious matter. If the advantage is not written in anywhere other than the filed patent's specification, the advantage is totally new, and this means the subject matter has non-obviousness.