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.Has someone else already done this?
As an inventor, one of your first thoughts when you come up with the Mother of All Ideas is probably, Has someone else already done this? The only way to know for sure if you're the first is through a patent search. The search will tell you if your idea has been patented already and, if so, whether the patent is still in force. Here's how you do it.How to Patent Your Idea
Contrary to popular belief, you can't get a patent for something that's still in idea form; you must be able to apply your idea in a concrete way. This doesn't mean that you have to build a prototype of your invention before you can get a patent. However, you have to be able to draw or describe it in enough detail so that someone else could make it and use it. Have a question? Get an answer from a lawyer now!The Poor Man's Patent is a Myth
One of the undying myths of Patent World is that there is such a thing as a Poor Man's Patent. If you've never heard of it, the poor man's patent involves writing out a description of your invention and mailing that description to yourself. The transmission of this description through the mail and the cancelling of the postage by the Post Office is supposed to establish a date of invention for you. That way if someone steals your invention or comes along and invents it independently, you have "proof" that you invented it first. The proof is in the sealed envelop and the date the postage was cancelled.More on Prior Art
Remember, while patent searching is a big part of prior art , it is not everything. If someone has made your invention before you without patenting that still counts against your patentablity. A complete search for prior art might include for example: searching non-patent literature such as any magazine, newspaper, or trade paper article written about inventions like yours also a complete search would include international patent documents (online) and not just those found at the USPTO. Do not make the mistake of believing that just because no one else is selling your product that it does not already exist. After determining that your idea is patentable and qualifies for a patent - you now need to decide if the expense of patenting is worth it.