Patent term: When does a utility patent expire?

How long does a utility patent last?

Generally, a utility patent expires 20 years from the filing date [35 USC 154(a)]. This 20-year patent term begins at the filing date of the first U.S. non-provisional application, which includes the filing date of an international PCT application. Foreign priority dates are not considered in determining the term of a patent.

Here’s a simple formula for calculating the expiration date of a US utility patent. Start with earliest filing date of a US nonprovisional, which may be a PCT application which is considered a US nonprovisional application.

Provisional filing dates and foreign priority dates do not count towards the term.

What is the patent term of a US national phase application?

For a patent granted on a US national stage application, the term is 20 years from the international filing date of the PCT application designating the US.

What is the term if the earliest filing was a provisional patent application?

Provisional patent applications do not count towards the 20-year expiration date unless a petition is filed under 37 CFR 1.53(c)(3) requesting conversion. So one major advantage of filing provisional applications is extending patent-pending status for up to one year without starting the clock on expiration.

What is the lifespan of continuing applications?

If a continuing application is granted, the term is 20 years from the filing date of the earliest non-provisional application (aka parent application) which may be a US non-provisional or PCT application. When it comes to new subject matter, therefore, a shorter lifespan is a strategic trade-off to consider in filing a CIP versus a standalone application which would get a fresh twenty-year term.

Does a foreign priority date affect the patent expiration date?

Foreign priority applications under the Paris Convention do not count towards the patent term.

What are patent term adjustments?

Patent Term Adjustments (PTA) calculated on a case-by-case basis by the USPTO could add a significant number of days, possibly years, to the 20-year term for utility patents.

Does the US have patent renewals?

US utility patents have something similar to renewals, but with a different name. Utility patents are technically not “renewed,” but “maintained” meaning that an issued utility patent will stay enforceable through its term as long the maintenance fees are timely paid. There are three maintenance fee deadlines falling on the:

  1. 3.5 year anniversary of the patent issue date;
  2. 7.5 year anniversary; and
  3. 11.5 year anniversary.

Therefore, it’s possible for a US utility patent to expire prematurely for failure to pay a maintenance fee. When conducting an infringement analysis of a utility patent older than three years, it would be prudent to check the payment of maintenance fees to see if the patent is current.

US design patents have no maintenance or renewals. The design patent term is 15 year from the grant date for design applications filed on or after May 13, 2015.

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