The USPTO does not calculate expiration dates for patents. In response to patent owner and public inquiry, the USPTO provided a downloadable patent term calculator as a resource to help the public estimate the expiration date of a patent. The calculator can be used to estimate the expiration dates of utility, plant, or design patents. The calculator contains prompts to enter specific information related to the patent in order to help in estimating expiration dates. A link to the calculator can be found here.
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