What is Patent Length?

Patent length refers to the term or lifespan of a patent. Once a patent application has been filed with the United States and approved by the United States Patent and Trademark Office, it will have a lifespan of 20 years.

Determining Whether a Term of a Patent is Linked to Another Patent Term

There are instances when certain patents will have a lifespan that is shorter than the typical 20 year term. This happens when the patent’s term is limited due to terms from other patents that were already issued in the past. For example, if two separate applications were filed with each application attempting to claim the same invention, the patent term could be shorter. When this happens, it is known as a terminal disclaimer.

If you believe this could affect your patent application, check out the USPTO Public PAIR system and go to the Image Filer Wrapper to see if the terminal disclaimer is already listed there. Sometimes the patent might not have an Image File Wrapper because it is too old. If this is the case, click the “continuity” tab in the PAIR system. If you find only one earlier patent, it is almost guaranteed that the terminal disclaimer is registered to that existing patent.

After finding this patent, you have to go through all the steps for it. Eventually you will discover the expiration date that both of the patents share. Upon learning which patent the terminal disclaimer was made for, you will want to ask why the terminal disclaimer was formed in the first place.

In many cases today, terminal disclaimers are routinely referred to as “full statutory term” of a previous patent. In the event that there was an extension on the patent’s term, “full statuary term” often includes the amount of time that the term was extended for.

When you look at the terminal disclaimer of a patent, if it clearly disclaims any terms after a certain date and doesn’t mention terms for additional patents, that particular date determines the term for the patent. Before 1995, this was a common practice. There was no such thing as a term extension and all patent terms began at the start of the patent’s issue date. Today, it is very unlikely that you would find this practice still being used.

Years ago, terminal disclaimers (or TD’s as they were once referred to as in the past), provided the date that the previous patent would expire on. These older terminal disclaimers also clearly stated that the disclaimed term was the previous patent’s term.

In many cases, when you look at the “specified date”, it is set by the previous patent’s term. This is still applicable even when the expiration date might be later than the specific date. The majority of these cases occurred because the law had been changed and this put an extension of all of the previous patents’ terms. The patent law change that happened in June of 1995 extended terms from 17 years at the time of issue to 20 years at the time of filing. Any time a terminal disclaimer was filed, the majority of the time the standard date of expiration and the specific date had the same 17 year lifespan from the time of issue.

The whole point of a disclaimer was to connect the later patent’s term to the earlier patent’s term. Because of this, the courts and the PTO did not believe that the laws regarding patent length would change or be extended past the listed date and in turn the actual term was set to provide a greater level of fairness.

Typically, patents that were filed after June 1995, had a 20 year lifespan at the time of filing, and were the “offspring” of the original patents, were considered continuations of the previous patents. And in these cases, a terminal disclaimer would not have much power or practicality to offer.

How to Know if the Basic Term Was Extended?

If a patent application was filed on or after the May 29, 2000 actual filing date, it is possible that the Patent Office might have extended their term lengths, but with certain limitations. These extensions (also known as “patent term adjustments”) are granted instantaneously at the time of the patent being issued. You can typically see the extension marked on the patent with a “(*)”.

Be aware that any patents issued anywhere between the months of August 2009 and March 2010 are subject to a special rule: It was decided that the USPTO was incorrectly calculating the adjustments of some patent length cases, according to the January 2010 Wyeth Decision. In certain situations, if there was an extensive delay in government approval for a patent, those patents would have their terms lengthened.

Anytime there is a patent term extension for FDA approval, the term is longer than the disclaimer date. In March of 20017, it was decided by the Court of Appeals for the Federal Circuit that patents subject to a terminal disclaimer would have any term extended for regularly reviews provided by section 156 of Patent Law (35 USC 156) after the terminal disclaimer date. This was decided in the Merck v. HI-TECH Case and any extensions that fall under section 155 could be handled in a similar manner.

Whenever there is a USPTO delay, the term does not extend beyond the disclaimer date. When there is a term extension granted due to a USPTO delay, those extensions full under 154 (USC 154(b)). This section states, “(B) Disclaimed term. No patent the term of which has been disclaimed beyond a specified date may be adjusted under this section beyond the expiration date specified in the disclaimer.”

How to Know if There was Any Reexamination or Voluntary Disclaimer Which Led to a Loss of Some or all of the Claims

If there was a voluntary disclaimer or a reexamination that prompted some or all of the claims to be lost, this information would be included on a certificate. This certificate would be provided with the patent and listed in the USPTO database (typically found in the image file on the last page).

In some cases (though it happens very rarely) the Commission of Patents would withdraw an issued patent from issue. When this happens, that patent is generally not going to be found on the USPO database. Once in a while that patent might be listed in other databases including Google Patents, EPO’s Espacenet, and other systems that you have to pay to use.

How to Know if the Required Maintenance Fees Have Been Paid on Time

Utility patents are subject to three basic maintenance fees. From the time of issue, they are due 3.5, 7.5, and 11.5 years later. There is a “payment window” for these maintenance fees and that window is open six months prior to each due date. That window close one year after the due date. If you pay your maintenance fees six months after the due date, you are subject to a surcharge. If for some reason you do not pay the maintenance fees during the one year grace period, your patent expires.

If you want to make sure that your maintenance fees have been paid on time, you can check the status of your payments by visiting the USPTO’s Patent Application Information Retrieval (PAIR) system. If you do not pay your maintenance fees and your patent expires, you will see a message that says “ERROR: There is no statement available for the selected payment year because the Patent has expired” instead of a payment window display that is usually in the PAIR system.

There are some instances when a patent could still be revived, even if it has expired after the maintenance fees were not paid on time. These patents can be revived if the late maintenance fee payments were unintentional.

How to Know if the Patent Was Declared Invalid by a Court?

A patent cannot be enforced in the event that it has been deemed invalid by the court. The tricky part is that is isn’t always easy to know whether or not a patent has become invalid. If you have reason to believe that your patent has become invalid, you could try looking it up in the Westlaw, Lexis, or BNA USPQ databases. To use these databases, you have to pay a fee. In these databases, you can look up your patent number to determine if your patent was brought up in a court case report.

If you acquire a case citation, you can go to the Public Access to Court Electronic Records (PACER) system to see if there is a case in which your patent was mentioned. An easier method of searching for your patent number is taking to Google and seeing if there is any information on reported cases that come up.

Of course, if you have good reason to believe you patent has been declared invalid, one of the best things you could do is hire a patent attorney to provide you with a patent opinion and validity study. When the patent attorney conducts a search, they will look for any prior art that could have rendered your patent invalid. The attorney will also examines your patent’s file to ensure nothing in it could affect your patent’s validity.

The Basics of International Patent Applications

If you filed an international patent application on or after June 8, 1995 and the patent was approved, that patent will have a 20 year term in the United States, beginning on the date it was filed. If you file either a continuation or a continuation-in-part patent application of a prior international application, it will have a 20 year term from the date the international application was first filed.

The Basics of Provisional Applications

Under 35 U.S.C. 119(e), domestic priority for a provisional application in the United States is not a factor when determining the 20 year patent term. Instead, the 20 year term is set at the time the non-provisional patent application has been filed. That non-provisional application has priority from any other provisional application that was filed previously.

Identifying Patent Application

The United Stated Patent and Trademark Office is the place to turn to for all relevant information regarding both pending and past patents. Anyone can take advantage of the online search engine provided by USPTO if they need to look up important patent information.

For all information related to your patent, you can visit the online search on the USPTO website and conduct your patent search. Before you can discover the lifespan of the patent you are looking up, you must first know whether the patent is a utility patent, plant patent, or design patent. If you are also looking up European patents, there is another search engine that you can use on the EPO website.

If you have a decorative, non-obvious, or unique product or an invention, that would fall under design patents. A decorative or unique products that qualifies for a design patent could include anything from patterns to furniture to public structures.

Obviously, if you know you have a utility patent, search the USPTO database for utility patents. Your product falls under the utility patent category if the project is functional and useful, not ornamental. If you have developed an asexually reproducing plant or a brand new variation of a plant, your invention would fall under the plant patent category. Other items that might be included under the plant patent category include mutations or hybrids. These plants might not necessarily have been invented, but discovered instead.

Need additional information related to patent length and all other matters regarding patents? Don’t hesitate to post your legal need on UpCounsel’s marketplace. UpCounsel accepts only the top 5 percent of lawyers to its site. Lawyers on UpCounsel come from law schools such as Harvard Law and Yale Law and average 14 years of legal experience, including work with or on behalf of companies like Google, Stripe, and Twilio.