What is reissue?
Patent law states "On taking up an application for examination or a patent in a reexamination proceeding, the examiner shall make a thorough study thereof and shall make a thorough investigation of the available prior art relating to the subject matter of the claimed invention." This means that prior art could disqualify your application for a patent.Meaning of Novel, Nonobvious, and Useful
New and Novel: For a United States patent the invention must never have been made public in any way, anywhere in the world, a year before the date on which an application for a patent is filed. Original and Nonobvious: An invention involves an inventive step if, when compared with what is already known, it would not be obvious to someone with a good knowledge and experience of the subject, for example, if you just make cosmetic changes that is obvious. Useful: This means that the invention must take the practical form of an apparatus or device, it has to do something.How To Conduct a Patent Search
you can do a patent search online. The U.S. Patent and Trademark Office (1790 - Present) and Delphion (1974 - Present) both provide free online databases. You can searching using keywords or phrases that describes your invention. Look for common terms describing the invention and its function, effect, end-product, structure, and use. The results will list the title and number of all patents related to your keywords (l976 forward only). The title link will take you to the full text of the patent. You will not be able to do a complete search online for a pre-1976 patent unless you know the exact patent number. With online patent be sure to examine other referenced patents that the inventor has listed.How To Qualify for a Patent
Difficulty: Hard - Time Required: Variable - Ask yourself if your invention can be adequately described or enabled -- can someone in the same field make and use it? Can you make your claim to the invention in clear and definite terms? A patent cannot be obtained upon a mere idea or suggestion and to obtain a patent, you need to be able to describe all aspects of your invention.What cannot be patented?
Laws of nature, Physical phenomena, Abstract ideas, Inventions which are considered not useful or possible by the USPTO for example perpetual motion machines; or offensive to public morality.