Accurately Determining Patent Expiration Dates:

Why It's Harder Than You May Think

Patents are expensive.  Patents are important.  You might think, therefore, that it would be easy to determine how long a patent lasts, right?

Sadly, you’d be wrong.

 

In the past, it was pretty easy:  The first US patent was granted 227 years ago today, on July 31, 1790.  It had a “term not exceeding fourteen years” as can be plainly seen at 1 Stat. 110.

 

Today, 35 USC 154 defines the term of a patent in the United States.  At present, that section of the US Code is more than 1,900 words long.  For certainty, you might also want to take a look at the USPTO’s Manual of Patent Examining Procedure section 2701 which adds another 1,500+ words of “clarity.”   Even for the US, though, we’re not done yet.  Among other provisions that bear on the subject, there’s also 21 CFR Part 60 (4,200+ words), 37 CFR Part 1, Subpart F (more than 20 sections for thousands of words), and on and on and on.   

 

Before your eyes glaze over from reading though, let’s consider a more step-by-step approach:

First, find the right patent term.  The baseline today is that the expiration date of a utility patent is 20 years from the filing date -- unless the application was made before June 8, 1995, in which case it is 17 years from grant.  (Don’t forget to calculate it both ways when applicable and use the longest.)  There are some other caveats with the application, though:  was it made before June 8, 1995 via the PCT process, or was it a provisional? 

Second, don’t forget that design or plant patents are different than utility patents. If you’re thinking of a design patent, do know that the rules changed on May 13, 2015. 

Third, whatever kind of patent you’re considering, make sure that the filing date is the “Earliest Effective Date.”  If there is an earlier Effective Date (perhaps you’re looking at a patent that issued from a continuation application, for example), make sure that you can claim “Domestic Benefit.”

The first US patent, which clearly had domestic benefit:

 

Fourth, with any sort of patent anywhere, you’ll want to check to be sure that any maintenance fees (AKA annuities) are paid on time.  And, even if they weren’t paid on time, see if they (and the appropriate penalties) were paid at all.

Fifth, now look for reasons that the term is different than the baseline term.  In the US, the most common reason for a difference is something called “Patent Term Adjustment.”  35 USC 154 addresses this item, which is mean to relieve the patent holder of undue delay by the USPTO in the course of processing the patent application.  Purportedly, 54% of recent US granted patents have some period of PTA.  Other governmental delays may extend the patent term, too.  For example, 35 USC 156 addresses Patent Term Extension which is meant to help offset the FDA drug approval process.

Sixth, see if the patent may have a shorter than expected term.  A patentee may file a Terminal Disclaimer either before or after the patent is granted, commonly to alleviate “double patenting” concerns. In a given patent family, there can be multiple applicable TD-related dates – so, be sure to select the earliest.

Seventh, speaking of the patent family, be sure to look for clues at each step (and in each related country) to see if there are other related applications that might change any of the above items (e.g. Earliest Effective Date).

Eighth, to find all of this data, you’ll primarily be looking at public data sources.  Depending the age of the patent, you might be lucky enough to find all of the relevant information in the USPTO’s Public Patent Application Information Retrieval (PAIR) system.  PAIR doesn’t generally have information from before 2003, so you’ll be looking for file history documents (aka file wrappers, image wrappers) for applications prior to that era.  Even for patents granted today, PAIR may not reach back far enough:  US patent 9,605,935 granted on March 28, 2017 with a term based on an application date of October 14, 1993.  Submarine patents are alive and well:

Ninth (and we’re not done yet), you’ll want to start thinking globally.  While I’m only licensed in the United States, every jurisdiction has its own unique set of laws and regulations that relate to patent terms.  While Article 33 of the Trade-Related Aspects of Intellectual Property Rights (TRIPS) agreement resulting from the Uruguay Round Agreements of the General Agreement on Tariffs and Trade (GATT) set the baseline term to 20 years from the application date globally, it did not mandate that there be no exceptions from this term (as the first eight points show!).   In Europe, for example Supplementary Protection Certificates affect IP protection:  these do not exist, as such, in the US.

So, finally, tenth:  now what?    If this all seems a bit much, there is always the option of hiring a licensed patent attorney who can arrive at the right date (and, potentially, back up those calculations with a malpractice policy).  The Medicines Co. v. Fish & Neave is an instructive case in considering the effect of a single day’s error in the practice of patent law.  With a lot of patents or a shortage of time, you might consider turning to an automated system.  There are all too many “patent term calculators” on the web which boil down to application date, plus 20.  And, even if you’ve made it through just half of the above, it’s clear that such a simple approach will produce the wrong answer all too often. 

 

Here’s the bottom line:  There is exactly one way to do this right – just follow the law.  And that’s the problem, because this is really quite hard to do.  Even more challenging from a global perspective, one has to follow each country's law (and don't forget to watch for changes in the law over the period of time you care about).  Reading between the lines, you can see that there are a nearly infinite number of ways to get it wrong; there are all too many traps for the unwary.

You are welcome, though, to use this article as a check list to help find a system that produces the most comprehensive and accurate legal status information possible.   As always, you should contact your attorney to obtain advice with respect to any particular issue or problem. This article is for informational purposes only and not for the purpose of providing legal advice.  For commercial overview purposes, a good automated system can help guide solid business decisions, but there’s no substitute for experienced legal counsel who is knowledgeable about the jurisdictions you care about and who is licensed in your jurisdiction.   

Happy patenting!