You Can't Be Too Obvious
Even if you don't find the prior art to prove it - you will not get a patent if your invention is not different enough from similiar inventions that are already out there. A patent maybe refused if the differences between your invention and another invention are too obvious. Your invention must be sufficiently different from what has been used or described before that it may be said to be nonobvious to a person having ordinary skill in the area of technology related to your invention . For example, the substitution of one material for another, or changes in size, are ordinarily not patentable. You can't paint it red and make it twice as big and expect a patent. Another example of "nonobvious to a person having ordinary skill in the area of technology related to your invention" could be the following. An electronics engineer looks at a circuit board and observes that it is just like another circuit board except that a few parts are substituted. Someone who is not familiar with circuit boards may not understand that the two boards are very similar, however, someone with training thinks that it is obvious. You would want the electronics engineer to look at the circuit board that you want to patent and say, "heah, why didn't I think of that!"patented invention
When you conduct the online patent searches, you'll be able to read the full text of the patents and see diagrams. Don't be discouraged if you do find your invention idea is already patented. You may be able to come up with a variation that's not patented...And double check the patent. Sometimes, what looks like the same invention idea may actually be quite different. Some of the free searches may not involve a complete search of all granted patent archives and patent applications for all time. You may want to consider hiring a registered patent attorney to find this information for you.How do I know if my idea is patentable?
First, check to see if your idea qualifies. Second, learn the basics of the patenting process. Next, do a search for of all previous public disclosures that concern your invention. These public disclosures are called prior art. A registered patent attorney or agent can be hired to do a patentability search for prior art, and a big part of that is searching for U.S. and foreign patents that compete with your invention. After an application is filed, the USPTO will conduct their own patentability search as part of the official examination process.What Does Useful Mean?
The patent law specifies that inventions must be useful, which means have a useful purpose. Being useful also includes operativeness, meaning that an invention must operate or perform its intended purpose.How to Conduct a Patent Search
To get a basic understanding of patent searches read Searching For Students and in particular read Searching Using Key Words . It was written for students; however, if you can look past the cute language it will quickly get you reading and searching patents online within minutes. It will not be enough to do a diligent (complete) search for prior art by only using the Internet. For that you would need to understand the patent classification system and be prepared to do days or even weeks of research.