Continuation application

The USPTO defines a continuation as an application for the invention or inventions disclosed in a prior-filed copending application. Its disclosure must not include any subject matter that would be new matter if submitted as an amendment to the parent³.

• Same disclosure. The disclosure of a continuation must be the same as the disclosure of the prior-filed application⁴.
• Common inventor. Under 35 U.S.C. 120 the later application must name an inventor or joint inventor named in the earlier application¹. The MPEP says the inventorship must include at least one inventor named in the prior-filed application³.
• Copendency. The continuation must be filed before the patenting or abandonment of, or termination of proceedings on, the earlier application, or an application similarly entitled to the earlier application's date¹. The earlier application is not automatically abandoned when a continuation is filed³.
• Benefit claim. The continuation must claim the benefit of the earlier application under 35 U.S.C. 120, 121, 365(c) or 386(c)³.
• Kind of earlier application. Each prior-filed application must be a nonprovisional application entitled to a filing date, or an international application designating the United States (or an international design application designating the United States)².

At any time before the patenting, abandonment, or termination of proceedings on an earlier application, an applicant may file a continuation under 37 CFR 1.53(b) to introduce a new set of claims and to establish a right to further examination by the Office³.

Claiming the benefit also fixes the patent term. Where an application contains a specific reference to an earlier application under section 120, the term of a utility patent ends 20 years from the filing date of the earliest such application, so a continuation does not start a new 20-year term⁵. Section 154 also provides for term adjustments; see patent term adjustment⁵. Separately, where two or more applications filed by the same applicant or assignee contain patentably indistinct claims, the Office may require elimination of such claims from all but one application, absent good and sufficient reason for keeping them (37 CFR 1.78(f))². Claims that are not patentably distinct from those of a commonly owned parent may also be rejected for nonstatutory double patenting, and a timely terminal disclaimer may be used to overcome that rejection (MPEP 804)⁷.

1. File while the earlier application is pendingCopendency means the later application is filed before the earlier one is patented, abandoned, or its proceedings terminated⁴. If the earlier application issues as a patent, filing on the same date as the issue date, or before it, is sufficient⁴. Patents issue shortly after the issue fee is paid, so applicants have limited time afterwards, and the MPEP says the best practice is to file before the issue fee is paid⁴.
2. Name a common inventorThe continuation must name at least one inventor or joint inventor named in the earlier application^1,2.
3. Add the benefit referenceA nonprovisional application must refer to each prior-filed application in an application data sheet, identifying it by number and stating whether the later application is a continuation, divisional or continuation-in-part². If the benefit is claimed through a chain of applications, the later application must also refer to the intermediate applications and to the first application⁴.
4. Meet the deadlineFor an application filed under 35 U.S.C. 111(a), the reference is due within the later of four months from the actual filing date or sixteen months from the filing date of the prior-filed application². The MPEP states the period is not extendable, and that failing to submit the reference in time waives the benefit unless a petition to accept an unintentionally delayed claim is granted⁴. Design applications are not subject to these time periods². The reference must be submitted together with any fee due under 37 CFR 1.17(w)², which applies when the continuation is filed more than six years after the earliest filing date for which benefit is claimed, and rises after nine years⁸.

A continuation does not automatically receive the earlier date for every claim. Under 35 U.S.C. 120 the invention must be disclosed in the earlier application in the manner provided by 35 U.S.C. 112(a), other than the best mode requirement¹. The MPEP states that the prior-filed application must provide adequate support and enablement for the claimed subject matter of the later-filed application⁴.

• Chains. Where there is a continuous chain of copending applications, each one must disclose the claimed invention of the later-filed application in the manner provided by 35 U.S.C. 112(a) for the later-filed application to be entitled to the earliest filing date⁴.
• Gaps in copendency. A later-filed application that is not copending with the prior application is not entitled to its filing date, and prior art against its claims is determined from the later application's own filing date⁴.
• Provisional applications. An application claiming the benefit of a provisional application under 35 U.S.C. 119(e) should not be called a continuation of it³. See provisional patent application.

The USPTO treats divisional, continuation and continuation-in-part applications as continuing applications, which differ in what they may contain⁴.

The Federal Circuit has applied the chain requirement of 35 U.S.C. 120 in an appeal from an inter partes review. The record below says nothing about either party beyond what the opinion states⁶.

The Board held that the challenged claims were not entitled to a priority date earlier than their own filing date of March 28, 2014, because the earlier applications did not provide sufficient written description, so a January 2010 publication was prior art. The Federal Circuit affirmed, stating that each application in the chain leading back to the earlier application must satisfy the written description requirement6.