What are the subjects and requirements for obtaining a patent registration?

The invention must not be known to the public at the time of filing (novelty), must demonstrate an advance over prior technology (inventive step), and must have industrial applicability (Article 29 of the Patent Act, requirements for a patent).

1. It must be an "invention" : Under the Patent Act, an invention means "a highly advanced creation of a technical idea utilizing the laws of nature."
   – Not inventions: methods of calculation, methods of drawing, methods of creating ciphers, computer programs (listings) themselves, hypnotism, methods of taxation, inventions relating to perpetual motion machines or unlimited power, etc.
   
   
2. Industrial applicability (Article 29, Paragraph 1, main text of the Patent Act)
   – "Industry" basically refers to production sectors such as manufacturing, agriculture, forestry, and livestock farming, but it also includes auxiliary industrial sectors such as transportation and traffic services.
   – "Insurance and finance businesses" and the "medical business" are excluded from industry.
   – Inventions lacking industrial applicability: inventions that can only be used for "academic or experimental" purposes, and inventions that do not fall under the "concept of an invention"
   
   
3. Novelty (Article 29, Paragraph 1, Subparagraphs 1-2 of the Patent Act) : Whether an invention has novelty is judged as of the time of the relevant patent application, so if a patent application is filed after the invention has become publicly known, in principle the invention is deemed to have lost its novelty. Even a technical creation that existed before filing and has not been registered as a patent cannot obtain a patent or utility model registration if, before filing, it was publicly known or publicly worked within the country, or was described in a publication distributed at home or abroad.
   
   
4. Inventive step (Article 29, Paragraph 2 of the Patent Act) : An invention with an inventive step means an invention that has a degree of creative difficulty such that a person having ordinary skill in the art to which the invention pertains could not easily make it from inventions publicly known at the time of the patent application.
   – A mere "aggregation invention" of publicly known inventions has no inventive step, and
   – A "combination invention" of publicly known inventions may, in some cases, have an inventive step.