Anticipated and Adjusted Expiration Dates

Anticipated and adjusted expiration dates are value-added dates calculated by IFI to provide the best possible estimate of when a patent is expected to expire.

Anticipated Expiration is based on the simple patent term formula. For recent US grants, this is 20 years from the earliest filing date. The full set of rules (for the US) is here: 

  1. Design patents (publication kind S, S1) - issue date + 14 years
  2. Reissues (publication kind E, E1) - use expiration date of parent (look up parent using related application type reissue)
  3. SIR, pre-grant publications (publication kind H, H1, In, An) - no date to calculate
  4. Utility patents, if issue date <=19780608 - issue date + 17 years
  5. Utility patents, if filing date >= 19950608 - earliest appdate + 20 years
  6. Utility patents, if filing date < 19950608 and issue date > 19780608 and issue date + 17 years > earliest appdate + 20 years - issue date + 17 years
  7. Utility patents, if filing date < 19950608 and issue date > 19780608 and earliest appdate + 20 years > issue date + 17 years - earliest appdate + 20 years

Different rules are applied in other countries.

Adjusted Expiration is Anticipated Expiration + Term Extension and/or Adjustment. For example, see the first page of US-8566251-B2:


In the "Notice" section, it says "Subject to any disclaimer, the term of this patent is extended or adjusted under 35 U.S.C. 154(b) by 96 days. This patent is subject to a terminal disclaimer”. 

The ifi-integrated-content section for this record is:

<ifi-integrated-content publication-type="G" accession-number="06146946" document-category="Utility" subject-area="Electrical">
  <ifi-patent-status anticipated-expiration="20310525" terminal-disclaimer="yes" adjusted-expiration="20310829">
    <ifi-patent-status-description country="US">Active</ifi-patent-status-description>
    <ifi-term-extension>96</ifi-term-extension>
  </ifi-patent-status>

The adjusted-expiration has 96 days added on due to the term extension. But note there is a terminal disclaimer. We do not know what is in that. So we tell you that there is one by adding a terminal-disclaimer flag, but we cannot adjust the date without more information.

Similarly, the presence of a regulatory-extension flag indicates that exploitation of a patent has been delayed by regulatory review (e.g., FDA review) or that a Supplementary Protection Certificate (SPC) has been issued for a patent.

IFI combines extensions and adjustments if both are present. For example, in US-6740669-B1, we see a patent term adjustment (PTA):

<term-of-grant>
  <us-term-extension>801</us-term-extension>
</term-of-grant>

as well as a patent term extension (PTE):

<office-specific-data>
  <ustags>
    <us-gazette>
      <us-extensions>
      ...
        <text>819 days</text>

The two are combined in the IFI term extension:

<ifi-integrated-content publication-type="G" accession-number="04072107" document-category="Utility" subject-area="Chemical">
  <ifi-patent-status anticipated-expiration="20180608" regulatory-extension="yes" adjusted-expiration="20221114">
    <ifi-patent-status-description country="US">Active</ifi-patent-status-description>
      <ifi-term-extension>1620</ifi-term-extension>

Litigation and actions such as appeal board reviews may also affect legal status. IFI has a blog post on this topic at The USPTO's PTAB is very busy - and why it matters.  

Therefore, "adjusted expiration" is just our best estimate of the expiration date. To get an exact date, you need to open up the file wrapper and see what the terminal disclaimers say, and see if any additional adjustments have been made.

For tips on searching anticipated and adjusted expiration dates, see Tips for Searching the IFI Snapshots.


Note: IFI’s Adjusted Expiration Date and Patent Status Indicator are useful estimates, but should not be considered authoritative or final results. An attorney or the relevant patent office should be consulted for an authoritative expiration and status determination.