What Everybody Ought to Know About Patent Expiration Dates

I personally think that one of the most useful features in AcclaimIP is our rolling expiration date field for US utility patents.

A rolling expiration date field lets you:
  • Find active patents coming up for renewal →  Plan budgets
  • Find active patents currently in their grace period, (between 3.5 and 4 years after grant date, for example) →  Catch mistakes, acquire patents
  • Find patents currently expired but still in their resurrection window →  Acquire patents that have previously expired.
The rolling expiration date field combined with a couple other fields called TRANCHE and EVENTCODE gives you all the power you need to analyze expiration and abandonment trends.  
So, let’s take a moment to learn about the powerful field code called EXPIRATION.

First, A Little Bit of Background on USPTO Patent Maintenance Requirements

US utility patents expire at years 4, 8 or 12 if maintenance fees are not received by the USPTO.  The fees are actually due before years 3.5, 7.5 and 11.5 but can still be paid within the six-month grace period if an extra $150.00 is submitted along with the standard renewal fees.  
After the 4, 8 and 12-year expiration dates, patents can only be reinstated with a significant surcharge and possibly a legitimate excuse.  Patents do get reinstated from time to time.  For example in 2012 there were 223 patents reinstated after they had expired in their E1 tranche.
The three expiration tranches are called E1, E2 and E3.  The fees get more expensive in each tranche.  The current maintenance fees for a large entity are $1,130, $2850 and $4730 for the E1, E2 and E3 renewal tranches respectively, and half this amount for small entities.
Note:  Tranche comes from the French word for “slice.”  As in, “Pardon mademoiselle.  Je voudrais une tranche de pain.”
Also Note:  US Design and Plant patents expire 14 years after issue and do NOT require maintenance fees.
Now that that is out of the way, let’s get to some powerful analyses.  

Using the EXPIRATION Field Code

Forget everything you thought you knew about patent expiration dates!  
When a patent is granted, we assign the patent to its first tranche, E1, AND we give it a rolling EXPIRATION date of IssueDate+4Years.   For example, all patents granted on February 12, 2013 were placed in the E1 tranche (the next renewal tranche) and given a rolling expiration date of February 12, 2017 (Exactly 4 years after the patents issue date, which is when they will expire if no maintenance payments are received by the USPTO). 
If we receive a maintenance payment event from the USPTO for the E1 renewal, we move the patent to E2 and move its rolling expiration date ahead by 4 more years.  We do the same thing at the E3 expiration tranche.  If the E3 is paid, we move the EXPIRATION date to the expected full term expiration date and move the TRANCHE parameter to EX.  
In the event the patent lapses and we receive an EXP (expired) event code, we don’t do anything.  The patent remains in E1 (or its last TRANCHE) and its expiration date remains ISSUE+4YEARS (or its last EXPIRATION), which is the date on which the patent expired (now in the past).  It is this approach that gives you power to fully query patents’ expiration dates.

Patent Expiration Analysis Example

Let’s say you want to find all patents in their E2 grace period.  You would use AcclaimIP’s advanced syntax to make a query that looks like this:
This query finds all patents that have an expiration date in the next 180 days for their E2 renewal—notice the date range in the EXPIRATION parameter.  All these patents are in their E2 grace period (that is, within six months of their E2 expiration date), which means they will be either abandoned, or the assignee will renew them but also pay the $150 late fee.  I think this is a good query to use when searching for patents to purchase because there is a good chance that the current owner is going to abandon them anyway.
Note:  I did a little analysis using the EVENTCODE field (Check out EVENTCODE in the help file).  In 2011 in E1, 7,028 patents were eventually renewed with late fees during the grace period out of the 27,770 patents that were in the grace period bucket at any time.  So you can expect about 25% will be recovered if trends hold in the future for E1.  Also in 2011, the E2 recovery rate for patents in their grace period was 14.4 percent and the E3 recovery rate was 10.6 percent.  
Some More Helpful Examples
A query like the following shows patents with an E2 renewal due, but not yet in the grace period.  The only change from the first example is the date range I used in the EXPIRATION parameter.  It is a handy query when planning your renewal budgets.
TRANCHE:EX finds all patents whose E1, E2 and E3 maintenance fees have been fully paid.  It is a good query to use when searching for patents that have fully survived all maintenance periods.
To search for expired patents all you have to look for is patents whose EXPIRATION date is in the past.  Use the EXPIRATION parameter and a wildcard range query.
EXPIRATION:[* to NOW]   → Expired patents
To show all active patents, search for patents whose EXPIRATION is in the future
EXPIRATION:[NOW to *]   → Active patents
An example of a Quick Search for patents in their E3 grace period and also in the OR class 705.
Let’s keep going.  If I want to find all expired patents whose E2 was paid but were abandoned in E3, just add the TRANCHE parameter.
See what is happening above?  The patent was renewed at E2, so the TRANCHE parameter was moved forward to E3 at some point, BUT the patent’s expiration date is now in the past [* to NOW], so it was not renewed at its E3 renewal, otherwise its TRANCHE would have been moved forward to EX and it’s expiration date would have been moved forward as well.
Now, say I want to do this same query but view IBM’s patents or Patents whose OR Class was 345…
A good time to approach a patentee about purchasing a patent is to find it before a maintenance fee is due.
[target parameters] AND EXPIRATION:[NOW to NOW+1YEAR] AND TRANCHE:E3
Where the “target parameters” are the other criteria you are using to reduce your set to patents that may be of interest to you.
Analytical charts such as the Abandonment Chart are automatically generated using the EXPIRATION and TRANCHE search fields.
The Help window has a Cheat Sheet that gives you 50 field codes you can search in and tips how to use them.  Just hover your mouse over the Field Code to see the tooltip.


In most cases, you will use our advanced query syntax to search for patents using the EXPIRATION and the TRANCHE search fields.   However, if you use the Refinement Panel on the Search Result window and choose a Legal Status as either Active or Expired, you’ll notice that AcclaimIP actually creates an EXPIRATION query for you.
But don’t fear, we give you plenty of examples in the Help file which you can find by going to Start>Help>Cheat Sheet!
Matt Troyer

Post navigation