13.4 Patent Term Extension Under 35 U.S.C. § 156

13.4 Patent Term Extension Under 35 U.S.C. § 156

Three different term concepts

Patent-term questions often place three separate rules in one fact pattern. The ordinary term for a modern utility or plant patent generally runs twenty years from the controlling nonprovisional filing date, subject to statutory qualifications. Patent term adjustment (PTA) under 35 U.S.C. § 154(b) adds days for specified USPTO examination delays, net of applicant delay and overlap. Patent term extension (PTE) under 35 U.S.C. § 156 instead restores part of the time lost while a patented product undergoes a qualifying federal regulatory review before commercial marketing or use.

The distinction controls which facts matter. An examiner delay points toward PTA. Food and Drug Administration or other qualifying agency review points toward PTE. Maintenance fees and terminal disclaimers are separate issues and should not be used as substitutes for either calculation.

Eligible patents and products

Section 156 applies to specified human drug products, animal drug products, medical devices, food additives, and color additives that were subject to a regulatory review period before their first permitted commercial marketing or use. For an application to qualify:

• the patent must claim the approved product, a method of using the product, or a method of manufacturing the product;
• the patent must not have expired before the application is submitted;
• the patent must not previously have received an extension under § 156;
• the approved product must have been subject to a qualifying regulatory review period; and
• the permission relied upon generally must be the first permitted commercial marketing or use of that product under the governing provision of law.

Only one patent may be extended for the same regulatory review period. When more than one patent could cover the product, the owner must make the statutory election rather than obtain cumulative extensions. The application is made by the patent owner of record or its authorized agent and must identify the patent, approved product, approval date, regulatory review history, and the manner in which the claims cover the product or an approved use or manufacturing method.

The sixty-day application period

The ordinary filing period is 60 days beginning on the date the product first receives permission for commercial marketing or use. This is a statutory deadline, so ordinary prosecution extensions under Rule 1.136 do not rescue a late PTE application. The statute contains a special rule for approvals transmitted after 4:30 p.m. Eastern Time: for purposes of determining the first permitted marketing date, the approval is treated as occurring on the next business day. On an exam, use the facts given and calculate the window under § 156(d), not an Office-action response rule.

An applicant may need an interim extension when a patent will expire while regulatory review or the PTE determination is still pending. Interim relief has its own conditions and does not eliminate the need for a timely complete application.

Calculating and limiting the extension

The regulatory review period is divided into a testing phase and an approval phase. In simplified form, the statutory calculation counts one-half of the qualifying testing phase plus the qualifying approval phase. The USPTO and regulatory agency then apply important reductions:

1. time in the regulatory review period that occurred before the patent issued is excluded;
2. overlapping calendar days are not counted twice;
3. periods during which the applicant did not act with due diligence are subtracted; and
4. the remaining result is constrained by the statutory caps.

The extension itself cannot exceed five years. In addition, the patent term remaining after regulatory approval, including the extension, ordinarily cannot exceed fourteen years. Thus a raw regulatory-review calculation of six years is capped at five, and even a five-year result can be reduced further if it would leave more than fourteen years of patent life after approval.

Agency roles, diligence, and scope during extension

The regulatory agency supplies the review-period dates and publishes them for public inspection; the USPTO decides patent eligibility and the ultimate extension. An interested person may petition for a due-diligence determination under the applicable procedure. The owner must respond accurately because an unexplained interval in testing or approval work can reduce the extension.

During the extended period, enforceable scope is limited by § 156(b) to the approved product and permitted uses in the manner specified by the statute. PTE does not convert every claim in the patent into a broader monopoly. For a method-of-use claim, attention to the approved use matters; for a product claim, attention to the statutory definition of product matters.

Exam checklist

When a term problem mentions regulatory approval, ask in order:

Keeping that sequence separate from PTA prevents the most common category error: awarding regulatory-review time under the USPTO-delay formula or using the seven-year maximum PTA shorthand as a PTE rule.