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When Does a Patent Expire?


The U.S. comports with the World
Until December 8, 1994, the United States had held fast against reason in not knuckling under to the world’s impression that patent terms should be calculated from the date the patent was FILED, rather than the date the patent was ISSUED. On that date Congress came to its collective sense and comported U.S. patent law with the General Agreement on Tariffs and Trade (the “GATT Uruguay Round”). Prior to 1994, the U.S. patent terms of 17 years from the date of issue. That means regardless of whether you filed your patent yesterday, or in 1970, you received 17 years of protection from the date of issue.

Sinking Submarine Patents

Submarines patents, made famous by the prolific and inventive Jerome Lemelson. Mr. Lemelson filed hundreds of patent applications on everything ranging from bar codes to superconducting electrical cable. Instead of prosecuting these applications quickly toward issuance, however, Mr. Lemelson would delay their issuance, often until after another company had commercialized the technology. Since the Patent Office maintained patent applications secret, competing businesses had no idea their new technology was actually the subject of a “submarine patent.” This strategy led to the collection of over $1 billion in royalties. This strategy also led to the U.S. changing the term of patent protection to 20 years from filing, thereby undermining the devastating effects of submarine patents.

Dealer’s Choice
Patent applications filed on or after June 8, 1995 expire 20 years from their filing date. Applicants filing before this date have the option of having their patent expire either 20 years from the date of filing OR 17 years from the date the patent issues. So, we have three cases:

1) Patents issuing before June 8, 1978 – Expire 17 years from issuance.

2) Patents issuing after June 8, 1978, on applications filed before June 8, 1995 – Expire later of 20 years from filing date OR 17 years from date of issuance.

3) Patents filed on or after June 8, 1995 – Expire 20 years from filing date.

Early Withdrawal
The foregoing terms apply to most patents. However, in certain circumstances, the actual date of a patent’s expiration may vary from those dates. For instance, if the Patent Office caused delays in the issuance of a patent, which caused the patent to issue more than 3 years after the filing date, the Patent Office may extend the term of the patent by an amount equal to the delay. If you fail to pay the maintenance fees, or succeeding in torquing someone off, your patent may expire or be canceled. Cancellation usually occurs when someone complains to the Patent Office that one or more documents (usually other patents) were overlooked during the prosecution of the patent. In this case, the Patent Office can leave the patent “as is,” restrict the scope of the patent or cancel the patent immediately.

Now, go off and impress your significant other with your newfound knowledge of patent expiry.

Brett Trout

Hat tip to Mike for keeping me on my toes!

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