How does foreign priority affect patent term?

Foreign priority does not affect the calculation of patent term in the United States. As stated in the MPEP, Foreign priority under 35 U.S.C. 119(a)-(d), 365(a), 365(b), 386(a), or 386(b) is not considered in determining the term of a patent. This means that the 20-year term is calculated from the U.S. filing date, not the foreign priority date.

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Topics: Adjustments, And Extensions, MPEP 2700 - Patent Terms, MPEP 2701 - Patent Term, Patent Law, Patent Procedure
Tags: foreign priority, international applications, patent term