Dear Rich: I have come up with an idea and did a patent search to see if there was anything similar to what my idea was. There was something similar, but not exactly. The patent for that item expired in 2003 after unanswered payment requests. The original date was 1991 on the patent. So, if I submit a request for my idea, even though different in several ways, but some similar thoughts, will I get rejected? If what you're claiming has already been invented (the prior art), then your invention is not novel and will not be awarded a patent. But if you have modified a previously patented device, then you may be able to obtain a patent on your improvement or modification -- for example, if you invented a paper clip that changes color depending on how many sheets of paper it is holding, you could patent your process for color adjustment resulting from the clip's resistance (though not the basic paper clip invention). This article provides more details on improvement and "new use" patents.