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!"How long does patent protection last? (As of year 2005)
Utility and plant patents are granted for a term which begins with the date of the grant and usually ends 20 years from the date the applications were filed. You must make the timely payment of the appropriate maintenance fees. Design patents last 14 years from the date you are granted the patent. No maintenance fees are required for design patents.Attorney Fees / Invention Complexity
The USPTO, IP Watchdog and every patent law firm strongly recommends that inventors hire a patent agent or attorney to prepare the application. IP Watchdog reminds inventors that not only is the process confusing, but a patent is a legal document that uses the language found in the application and patents can only be protected in court, where every word in the document matters. IP Watchdog reports that the median cost of a patent attorney is around $250 an hour, higher in urban areas (Quinn suggests hiring an experienced attorney that works in an area with a low cost of living as a way to control costs, as opposed to hiring an inexperienced attorney). Quinn states that, depending on the complexity of the invention, attorney fees for conducting a search and preparing an application with drawings usually run between $7,000 and $15,000. The more complex an invention, the longer the attorney spends researching related patents, writing up a detailed description and outlining exactly what the patent should protect. Drawings also take longer the more complex the invention is, and USPTO rewrites can be more difficult.What You Can Patent
A patent provides you with the right to keep others from making and selling your invention for up to 20 years. The most common type of patent, a utility patent, protects rights in new and useful processes, machines and other things. These patents also can protect rights in non-obvious improvements made to existing things. To determine if your invention is patentable, you must first research all previous patents and other publicly disclosed inventions to ensure that no one else has already patented something similar. Because this process can be difficult and complicated, the U.S. Patent and Trademark Office recommends hiring a registered patent attorney to conduct the search for you.Patent Attorney Directed Search
Going through a lawyer to search patents will cost the least amount of time and the most money. Patent attorneys employ professional researchers. You hire the attorney, and the attorney gets someone to conduct the search. Then the attorney adds a mark-up to the search bill, sometimes as much as several hundred percent. Many lawyers cloak this in the term handling fee. To save this extra expense, some inventors hire their own researcher or do the search themselves. Most patent attorneys don't render an opinion based on a search conducted by anyone other than their own searcher. However, you can tell a lawyer that if they won't accept the work of your search firm, or searches done by yourself, you will go elsewhere where such work would be acceptable. If you're paying the bills, and you're willing to take the risk, the lawyer shouldn't have a problem. Now, if the search results show no prior art in my field of invention, you don't need an attorney to tell me the coast is clear. Conversely, if a search reveals prior art that's spot on your invention, you don't need an attorney to tell me my idea has been done before. You might, on the other hand, hire an attorney to help end-run an existing patent through the use of language in the application. If you hire a lawyer, get a quote in advance. The fee will be based on how all-encompassing you want the search to be.