Continuing patent application
A continuing patent application may be one of three types: a continuation, divisional, or continuation-in-part application. While continuation and continuation-in-part applications are generally available in the U.S. only, divisional patent applications are also available in other countries, as such availability is required under Article 4G of the Paris Convention.
From 1838 to 1861, inventors could file patent applications on improvements to their inventions. These were published as "additional improvement patents" and were given numbers preceded by "A.I.". About 300 of these patents were issued.
Current law in the U.S.
Under the law in the U.S., inventors may file several different types of patent applications to cover new improvements to their inventions or to cover different aspects of their inventions. These types of patent applications include "continuation", "divisional", "continuation in part", and "reissue".
|Summary of continuing patent applications in the US|
|Type||Disclosed in parent?||Claimed in parent?|
A "continuation application" is a patent application filed by an applicant who wants to pursue additional claims to an invention disclosed in an earlier application of the applicant (the "parent" application) that has not yet been issued or abandoned. The continuation uses the same specification as the pending parent application, claims the priority based on the filing date of the parent, and must name at least one of the inventors named in the parent application. This type of application is useful when a patent examiner allowed some, but rejected other claims in an application, or where an applicant may not have exhausted all useful ways of claiming different embodiments of the invention.
During the prosecution of a continuation application, the applicant may not add additional disclosure to the specification. If the inventor needs to supplement the disclosure of the earlier parent application, he must file a continuation-in-part application.
In the typical case, a patent examiner will examine patent claims and amendments in an original patent application for two rounds of "office actions" before ending examination. However, often two office actions are not enough to resolve all of the issues in the patent prosecution.
Request for continued examination
A request for continued examination (RCE) is a request by an inventor for continued prosecution after the patent office has issued a "final" rejection. An RCE is not considered a continuing patent application - rather, prosecution of the pending application is reopened. The inventor pays an additional filing fee and continues to argue his case with the patent examiner. No RCE was allowed prior to June 8, 1995. See 37 CFR 1.114.
A divisional application also claims priority based on the filing date of the parent application, but differs from a continuation application in that a divisional application claims a distinct or independent invention "carved out" of the parent application. A divisional application must share at least one of the inventors named in the parent application. A divisional application is often filed after the examiner issued a "restriction requirement", because a patent can only claim a single invention (cf. unity of invention).
A "continuation-in-part" application ("CIP" or "CIP application"), claiming priority based on the filing date of the parent application, is one in which the applicant adds subject matter not disclosed in the parent, but repeats substantial portion of the parent's specification, and shares at least one inventor with the parent application. The CIP application is a convenient way to claim enhancements developed after the parent application was filed. It is the successor to the earlier "additional improvement" patents mentioned above.
If an issued patent is found to be defective, then the patent owner can surrender the patent and refile the original application to correct the defect. One such defect occurs when the issued patent fails to claim the full scope of the disclosed invention. Thus, an inventor can submit the patent application again with broader claims and attempt to get the full coverage he is entitled to. The inventor is not, however, allowed to add new features to the invention.
An issue application which attempts to get broader coverage than the originally issued patent must be filed within two years from the grant date of the said originally issued patent.
Controversy around attempted changes by USPTO to continuation practice
In 2007, USPTO announced new regulations under 37 CFR (published August 21, 2007) that would significantly alter procedures regarding continuation application before the USPTO. Previously, USPTO rules allowed an inventor to file as many continuations as necessary to get desired breadth of claims. The procedure was criticized for creating uncertainty as to what is covered or could be covered by a given patent application. An inventor, for example, could have sought to get claims with limited scope approved early, and then continue to file continuations over many years seeking broader coverage. For example, inventor Jerome H. Lemelson filed a series of continuations over thirty years to get a very broad patent on bar code readers. This patent was issued in 1984, long after bar code readers had become an integral part of the U.S. economy. Jerome Lemelson was then able to collect over a billion dollars in license fees from large companies using bar code readers. (Of note, the Lemelson optical recognition patents followed the old 17-year rule. For patents filed 8-June-1995 or later under the TRIPS agreement, continuation patents expire 20·years from the date of filing of the parent patent application.)
To minimize this alleged abuse of the patent system, the USPTO proposed several changes to the rules as to the number of continuations an applicant can file. The proposed changes were announced on January 3, 2006, and were published in final form on August 21, 2007, after various modifications were made pursuant to input received as public notice and comment (during which the public was invited to comment on the proposed rule changes). Many of the provisions in the new rules went into effect November 1, 2007; however, certain additional exemptions apply for continuation applications filed before the publication date of August 21, 2007, even after November 1, 2007.
The proposed rules would have limited an inventor to filing two continuation applications for each type of invention disclosed in an original patent application, unless the applicant can show "good cause" for filing additional continuations. Furthermore, applicants could file only one RCE for each "family" of applications (that is, the group of applications including original applications and each of the continuation applications claiming the benefit of priority of the original application) unless the USPTO granted the applicant permission upon showing "good cause."
The proposed changes were generally opposed by patent agents and attorneys, manufacturing companies, biotechnology companies, and independent inventors. There was concern that the rule changes failed to consider the difficulties commonly encountered in getting a patent, and that the changes would result in inventors failing to get the full range of patent protection to which they are entitled. The groups also maintained that the rule changes were not consistent with the current regulations on continuations.
The rule changes were generally favored by software companies, electronics companies and US government agencies for the reasons given above. Those that favored the rule changes felt that said changes were consistent with the laws governing continuation practice.
On August 22, 2007, inventor Dr. Triantafyllos Tafas sued the USPTO in the United States District Court of the Eastern District of Virginia on the ground that the rule changes were in violation of the U.S. patent law and therefore are invalid. On October 9, 2007, pharmaceutical company GlaxoSmithKline filed a similar suit seeking a preliminary injunction to prevent the enforcement of the new rules. The court consolidated the two cases and scheduled a hearing on GlaxoSmithKline's motion for October 31, one day before the rules were to go into effect. On October 31, the court granted a preliminary injunction which prohibits the USPTO from enforcing the patent rules on continuations and claims which were to come into effect the following day. On April 1, 2008, the injunction was made permanent,  but in March 2009, it was overturned by Federal Circuit Court of Appeals. 
In October 2009, USPTO withdrew proposed changes to continuation rules. 
- M.P.E.P. 901.04 U.S. Patents Prior Art, Classification, and Search
- "201.08 Continuation-in-Part Application [R-3] - 200 Types, Cross-Noting, and Status of Application". Retrieved 01/24/2012.
- 35 U.S.C. 251 Reissue of defective patents.
- USPTO web site, Comments on Proposed Changes to Practice for Continuing Applications, Requests for Continued Examination Practice, and Applications Containing Patentably Indistinct Claims, Notice of proposed rulemaking
- USPTO web site, Claims and Continuations Practice - Final Rule (www.uspto.gov)
- USPTO web site, American Intellectual Property Law Association comments on proposed rule changes for Continuation practice
- USPTO web site, Honda R&D Americas comments on proposed rule changes to Continuation practice
- USPTO web site, Biotechnology Industry Association comments on proposed rule changes for Continuation practice
- USPTO web site, Inventors Alliance comments on proposed rule changes to Continuation practice
- USPTO web site, Business Software Alliance comments on proposed rule changes for Continuation practice
- USPTO web site, Intel comments on proposed rule changes to Continuation practice
- USPTO web site, The Antitrust division of the US Department of Justice comments on proposed rule changes for Continuation practice
- Dr. Tafas Files Declaratory Judgment Action to Block Implementation of Continuation Rules, Patently-O Blog, August 22, 2007[unreliable source?]
- Another lawsuit filed to stop implementation of new USPTO rules, this time by a heavy hitter, Filewrapper Blog, October 11, 2007[unreliable source?]
- Glaxo's preliminary injunction motion to be heard October 31, consolidated with earlier challenge, Filewrapper Blog, October 19, 2007[unreliable source?]
- Preliminary Injunction Granted to Block New Rules on Continuations and Claims from Taking Effect Tomorrow, Intellectual Property Owners Association, October 31, 2007
- Jim Singer, Court Issues Permanent Injunction Against USPTO Patent Rule Changes, IP Spotlight blog, April 1, 2008.
- Federal Circuit largely backs USPTO limits on patent claims and RCEs; strikes down limits on continuations
- USPTO Rescinds Controversial Patent Rule Changes Proposed by Prior Administration