35 U.S.C. - Written Description

Erroneous claims to priority

Before the change in the patent law in 1995, a patentee could effectively extend the life of a patent through continuation practice. Continuation practice allows certain types of patent applications to claim priority back to a previous application.

The effect of the continuation practice, especially when done in repetition, is that prosecution time may be extended over a long period of time. The patent law permits “chains” of continuation applications. Indeed, there is no limit to the number of applications in the chain. In Re Henriksen, 399 F.2d 253 (CCPA 1968). In a long chain, each application is given the priority of the parent application. This results in, in extreme cases, prosecution times ranging over decades. See Mark Lemley & Kimberly Moore, Ending Abuse of Patent Continuations, 84 B.U. L.Rev. 63 (2004) (noting the “egregious” example of Jerome Lemelson who filed “eight of the ten continuation patents with the longest delays” with several applications taking more than 40 years). This is no longer an issue under modern practice.

In general, new applications are given a twenty year patent term from the priority date. 35 U.S.C. §154(a)(2). Therefore, delays caused by continuation practice prolong prosecution and reduce the period of patent protection. Where the chain of priority reaches too far back, the patent term is shorten. Continuation practice is premised on the idea that each subsequent application essentially claims the whole or part of the invention, which is disclosed in the parent. Over the course of a long prosecution, this may no longer be the case and amending this chain would be appropriate. The issue then is whether an applicant may break the chain of priority for an issued patent or for a patent application.

There are two situations that need to be examined: the effect on an issued patent and the effect on a pending application.

An issued patent

The patent law permits corrections to issued patents. The law states “Whenever any patent is, through error without any deceptive intention, deemed wholly or partly inoperative or invalid, by reason of a defective specification… the Director shall… reissue the patent for the invention disclosed in the original patent, and in accordance with a new and amended application, for the unexpired part of the term of the original patent.” 35 U.S.C. §251.

Erroneous claim to priority is a legitimate ground for reissue. A reissue application must contain “at least one error in the patent.” Id. For a patent to reissue, the error must be one which makes the patent “wholly or partly inoperative or invalid.” 35 U.S.C. §251. The PTO recognizes that an applicant’s failure to make reference to or incorrect reference to “prior copending applications” is one of the “most common bases for filing a reissue application.” MPEP §1402. The courts have also noted that claims to priority have been held as valid grounds for reissue. MPEP §1402 cites Brenner v. State of Israel, 400 F.2d 789 (D.C. Cir., 1968) and Sampson v. Comm’r Pat., 195 USPQ 136, 137 (D.D.C. 1976).

However, a reissued patent cannot alter the patent term. The “maximum term of the original patent is fixed at the time the patent is granted.” MPEP §1405. 35 U.S.C. §251 only permits a reissue “… for the unexpired part of the term of the original patent.” Therefore, a change in the chain of priority will not effect the patent term. Indeed, in the MPEP, the patent office states that if the sole error is a change in priority and the sole reason for the reissue is to increase the term of the patent, the reissue will be rejected for failure to identify an error. Id. Where either other issues or other reasons for the change in priority are claimed, the reissue application will be examined and potentially reissued with the amended priority. Id.

A pending patent application

Slightly more complicated, but effective, is an amendment to a pending application.

For divisional or continuation-in-part applications, a reference to the parent application needs to be in the “first sentence of the specification or in an application data sheet.” 37 CFR §§ 1.78(a)(2) and (a)(5). A CPA’s specific reference is implicitly met by the legal requirements of 37 CFR §§ 1.53(d)(2)(iv) and (d)(7). The ordinary result of such a reference is that the application is able to claim the “benefit” of the priority date. As noted earlier, long chains of priority shorten the patent term. The PTO notes that as “a result of the 20-year patent term, it is expected, in certain circumstances, that applicants may cancel their claim to priority by amending the specification or submitting a new application data sheet.” MPEP §201.11(III)(g). As such, CIP and divisional applications is done under the ordinary rules outlined in 37 CFR §1.121(b) to amend the specification.

Amend a continuing prosecution application creates a new patent. A CPA’s reference to the parent application is a legal requirement which is implicit to the application. As such an applicant cannot easily delete the specific reference to a prior application for a CPA. To amend a CPA’s specific reference, the application is, among other things, returned to the Office of Initial Patent Examination. This in effects creates a new patent application.

The “happy” result of the amendment is that the chain of priority is shortened and the patent term is extended. The current patent law calculates the patent term, generally, as twenty years from the priority date. Where the chain of priority is successfully amended, the priority date will be nearer. Therefore, the patent term is extended by an equal amount.

Beware of new prior art

There are repercussions where an applicant can seek and does seek an amendment. The PTO recognizes two significant effects of such an amendment. The first is that cancellation may create “new prior art” which the examiner needs to consider. MPEP §201.11(III)(g). The sine qua non of continuation practice is that each continuation be fully disclosed in the parent application that application may create prior art. Therefore, such an amendment should be reserved where the inclusion was actually erroneous. The second is that “cancellation… may be considered as a showing that the applicant is intentionally waiving the benefit claim to the prior application.” Id. This may later affect the applicant’s later ability to file a “petition to accept an unintentionally delayed claim to add the benefit claim to the prior application.” Id.

posted by Mike @ 6:16 AM