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Calculating Patent Term Adjustment (PTA) – An Overview

Patent application in a folder

As discussed in our previous post, Patent Term Adjustment (PTA) under 35 U.S.C. §154(b) and Patent Term Extension (PTE) under 35 U.S.C. §156 provide for extensions on the standard patent term, which can be very valuable for products that have long development and/or regulatory approval lifecycles, such as in the case of pharmaceuticals.

This post will focus on the calculation of PTA, which is intended to adjust the patent term to compensate for delays caused by the U.S. Patent and Trademark Office (USPTO) during the examination process. PTA can be calculated as:

 PTA = (Days of PTO delay) – (Days of Applicant Delay)

Days of PTO delay (35 U.S.C. 154(b)(1))

Days of PTO delay can be calculated as:

Days of PTO delay = A-delay + B-delay + C-delay – AB Overlap

A-delay: 35 U.S.C. 154(b)(1)(A) = Promptness of Patent and Trademark Office Response

This type of PTO delay is sometimes colloquially referred to as “the 14-4 Rule” and provides for PTA extension in the following scenarios:

(i) When the USPTO fails to issue a notice, i.e., mail a restriction requirement, a non-final office action, or a notice of allowance, within 14 months after the application filing date
(ii) When the USPTO fails to respond to an applicant’s Reply within 4 months
(iii) When the USPTO fails to respond to a Patent Trial and Appeal Board (PTAB) decision within 4 months
(iv) When the USPTO fails to issue a patent within 4 months after issue fee has been paid

A-delay extends the patent term by 1 day for each day after the end of the period specified in (i), (ii), (iii), or (iv), as the case may be, until the action described in the relevant clause is taken.

B-delay: 35 U.S.C. 154(b)(1)(B) = No More Than 3-Year Application Pendency

PTA is extended 1 day for each day after the end of the 3-year period until the patent is issued. However, B-delay excludes time consumed by an applicant for (1) filing a Request for Continued Examination (RCE), (2) appeals, interferences and secrecy orders, and (3) applicant requested a delay. Notably, for the filing of an RCE, B-delay accrues only for the time before RCE filing date. That is, a patent application does not earn a B-delay from the time an RCE is filed until a Notice of Allowance is issued unless the USPTO actually resumes examination of the application after allowance. For appeals, interferences, and secrecy orders, the time may be recovered under C-delay.

C-delay: 35 U.S.C. 154 (b)(1)(C) = Derivation Proceedings, Secrecy Orders, and Appeals

C-delay provides an extension for delays caused by PTAB appeals, interferences, or secrecy orders. Although an appeal terminates the B-delay clock, part of an appeal may be counted as C-delay if the appeal is successful.

Overlapping Delays

Where A-Delay and B-Delay overlap, the extension does not exceed the actual number of days the issuance of the patent was delayed. This rule prevents the overlap in A-Delay and B-Delay from being counted twice.

Days of Applicant Delay (35 U.S.C. 154(b)(2))

PTA is reduced by “the period of time during which the applicant failed to engage in reasonable efforts to conclude prosecution of the application” (see,35 U.S.C. 154(b)(2)(C)). Common circumstances considered as falling within 35 U.S.C. 154(b)(2)(C) include:

  • Petition for extensions of time for responding to an office action
  • Filing an incomplete reply (e.g., non-responsive or non-compliant amendments)
  • Submitting a supplemental reply or “other papers” unless expressly requested by the Examiner
  • Submitting an Information Disclosure Statement (IDS) after a response to an Office Action (unless accompanied by a 37 CFR §1.704(d) statement or “the 30-day statement,” which essentially states that the IDS was filed to submit information cited in a counterpart foreign application, received within 30 days of the IDS filing)

Terminal Disclaimers

Terminal disclaimers cut off the term of a patent after any PTA has been applied, but before any PTE has been applied. Thus, the filing a Terminal Disclaimer can cause a patentee to lose portions or all of the PTA accrued.

Petition for PTA Correction

If a patentee is unhappy with the PTA automatically calculated by the USPTO, a petition for reconsideration can be filed no later than two months from the date the patent was issued; this deadline can be extended by up to 5 months with payment of appropriate extension of time fees.

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