Patent Term Adjustment: Maximising Patent Protection


In the world of innovation and intellectual property, patents play a crucial role in protecting an inventor’s rights and ensuring fair competition. However, the time taken for patent examination and processing can impact the effective lifespan of a patent. To address this concern, the United States Patent and Trademark Office (USPTO) introduced the Patent Term Adjustment (PTA) system. PTA allows for additional time to be added to a patent’s term, compensating for delays in the examination process. This article delves into the concept of PTA, its importance, and the factors affecting its calculation.

What is Patent Term Adjustment (PTA)?

The Patent Term Adjustment is a mechanism employed by the USPTO to offset any delays that occur during the patent examination process, beyond specific timeframes set by law. These delays can result from the USPTO’s actions or applicant-requested extensions. By extending the patent’s term, the USPTO aims to ensure that patentees receive the full term of exclusivity that they are entitled to, despite the time taken for examination.

Understanding the Basis for Patent Term Adjustment

The USPTO calculates Patent Term Adjustment based on two primary factors: the USPTO’s responsibility for delay and the applicant’s responsibility for delay. These factors are evaluated independently, and the final PTA is determined by subtracting the Applicant’s delays from USPTO delays.

USPTO’s Responsibility for Delay:

The USPTO sets specific timeframes within which certain actions should be completed during the patent examination process. If the USPTO exceeds these timeframes, it is considered a delay for which the office is responsible. Some common causes of RFD include, but are not limited to:

Failure to meet statutory deadlines for various examination actions.

Taking an excessive amount of time for search and examination.

Not issuing a first office action within a specified timeframe.

Applicant’s Responsibility for Delay:

While the USPTO aims to expedite the patent examination process, applicants can also contribute to delays by requesting extensions, filing incomplete responses, or delaying the prosecution without proper cause. Such delays are attributed to the applicant and are deducted from the PTA calculation.

Patent Term Adjustment Calculation

The USPTO follows the following formula to calculate the Patent Term Adjustment

Total PTA = Type A + Type B + Type C – Applicant Delay – overlapping delays.


A = Total days of USPTO’s responsibility for delay

Type A delay occurs when the USPTO fails to reply within the time period provided. As per U.S. Patent law:

  • The USPTO has to issue the First Office action within 14 months of filing of the application.
  •  All other office actions have to be issued within 4 months of receipt of an applicant response.

B = Delay between date of filing and grant of a patent

Type B delay occurs if time period of three years exceeds between the date of the filing of the application and the issue of the patent.

  • Type B delay will be calculated if no RCE (Request For Continued Examination) is filed prior to completion of the three-year period.
  • If an RCE is filed after the three-year period, then the Type B delay will be calculated up to the date of the filing of the RCE.
  • Type B delay = Date of issue of Patent/Date of filing of first RCE – (Date of filing of application + 3 years)

It is to be noted that the filing of RCE is considered as an applicant’s delay and not an exception to B-delay if it is filed after Notice of Allowance (NOA).

C = Overlapping days of delay that count only once

These delays caused by interference or derivative proceedings, secrecy order and patent appeal at PTAB, provided the outcome of such are in the favor of the applicant

Applicant Delays

Applicant delay occurs when the applicant fails to engage in reasonable efforts to conclude prosecution.

  • When the applicant fails to respond to the Office Action within 3 months.
  • IDS submissions one month prior to issuance of office action
  • IDS submissions after issuance of Notice of Allowance

Significance of Patent Term Adjustment

The Patent Term Adjustment system is designed to protect patentees’ rights and encourage innovation by mitigating delays that occur during the examination process.

For industries with lengthy regulatory approval processes, such as pharmaceuticals and biotechnology, a substantial Patent Term Adjustment can be particularly valuable. It allows these industries to retain exclusivity for a longer period, safeguarding their market position and encouraging further research and development.


The Patent Term Adjustment system at the USPTO plays a vital role in ensuring that inventors and businesses receive the full benefits of their patent rights. By compensating for delays in the examination process, the PTA system promotes innovation and encourages investment in research and development. Understanding the calculation methodology and implications of PTA is crucial for patent applicants and holders to maximize the value and protection of their inventions in the ever-evolving landscape of intellectual property.

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