Patent term adjustment (PTA)

Section 154(b)(1) sets out three guarantees, each of which extends the term one day per day of delay¹. USPTO decisions label the resulting periods A delay, B delay and C delay⁸.

1. Add up the delay periodsThe adjustment is the sum of the A, B and C delay periods calculated under 37 CFR 1.703(a) to (e), to the extent they do not overlap³.
2. Count overlapping days onceWhere delay periods overlap, the adjustment cannot exceed the actual number of days the issue of the patent was delayed¹.
3. Subtract applicant delayThe adjustment is reduced by the time during which the applicant failed to engage in reasonable efforts to conclude prosecution¹. Under USPTO rules this includes any time beyond three months taken to reply to a notice making a rejection, objection, argument or other request⁴.
4. Apply any terminal disclaimerA patent whose term has been disclaimed beyond a specified date cannot be adjusted beyond the expiration date in the disclaimer¹. In addition, the Federal Circuit held in In re Cellect (2023) that obviousness-type double patenting for a patent that has received PTA must be judged on its expiration date after PTA is added, whether or not a terminal disclaimer is required or has been filed¹⁰. See Double patenting.

USPTO decisions state the result as a formula: PTA equals A delay plus B delay plus C delay, minus overlap, minus applicant delay⁸.

Other conduct the rules treat as applicant delay includes abandoning the application or paying the issue fee late, filing a supplemental reply that the examiner did not request, and filing a request for continued examination after a notice of allowance⁴.

• Determination. The USPTO determines the adjustment and must send notice of it no later than the date the patent issues¹. The patent itself includes notification of any adjustment⁵.
• Reconsideration. A request for reconsideration must be made by an application for patent term adjustment filed no later than two months from the date the patent was granted; this period may be extended under 37 CFR 1.136(a)⁵.
• Reinstatement of a reduction. All or part of a reduction for replies filed after three months can be reinstated if the applicant shows that, in spite of all due care, it could not reply in time. The request must be filed before the patent issues, and no more than three additional months per reply can be reinstated^1,5.
• Court review. An applicant dissatisfied with the decision on reconsideration may bring a civil action against the Director in the US District Court for the Eastern District of Virginia within 180 days of that decision¹.
• Third parties. A PTA determination cannot be challenged by a third party before grant, and the USPTO does not consider third party submissions on PTA^1,5.

The current rules in 37 CFR 1.702 to 1.705 apply only to original applications, except design applications, filed on or after May 29, 2000, and to patents issued on them². Section 154(b) was amended with effect from that date, and again by the Leahy-Smith America Invents Act in 2011 and the AIA Technical Corrections Act in 2013⁷.

When prosecution continues through a continuing application, the adjustment does not include any period before the actual filing date of the application that resulted in the patent⁴.

China's Patent Law has a comparable rule. Where an invention patent is granted more than four years after the filing date and more than three years after the request for substantive examination, the term is extended at the patentee's request to compensate for unreasonable delay in granting it, except delay caused by the applicant (Article 42)⁹. The patentee must request it within three months of the announcement of grant (Implementing Regulations, Rule 77)¹¹.

Both lengthen a US patent's term, but for different reasons and under different statutes^1,6.

USPTO decisions on requests for reconsideration show the calculation in practice. The decision is shown for its calculation; it says nothing about the patentee beyond the record.

The patent issued with a PTA of 878 days: 689 days of A delay plus 219 days of B delay plus 0 days of C delay, less 0 days of overlap and 30 days of applicant delay. The patentee argued B delay was 554 days and sought 1,213 days; the USPTO confirmed 878 days8.