How Long Do Patents Last And What About Improvements To A Patent

Patents last 20 years from the date of filing. However, a patent on a base concept will not prevent you from applying for a patent on improvements to the base concept. For example, the cell phones of today are filled with innovations not present in Bell's original telephone. A patent gives you the right to exclude others, but not a right to practice the invention. For example, you could exclude others from using your improvements, but still not practice your invention without a license from the patentee of the base concept. However, if your improvements represent a desirable area of expansion for the company owning the base patent, this type of situation usually works itself out as a business deal between the two companies to cross license patents or work together.

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