In most cases, the dispute relates to a lack of specificity in identifying the error to be corrected in the patent reissue application. While in many cases the correction necessary is relatively minor. However, in most cases the objection raised relative to the oath does not come from the examiner, but instead, a Quality Assurance Specialist (QAS) of the USPTO. Thus, it is not uncommon to contact the examiner to request a recommended change to an oath to finally settle the dispute only to have the examiner inform you “I think it’s fine, but the QAS has some issue that I don’t really understand.” This leaves the Patentee with no efficient means to address the problem in a timely manner. This type of roadblock is especially aggravating in broadening patent reissue applications.

Oaths in broadening patent reissue applications cannot be executed by the patent owner, but must instead be signed by all inventors.  This requirement is especially onerous as patent reissue by definition requires that the inventors first obtain a patent—a  journey that can easily span 3-5 years, or more. At the time of filing the broadening reissue it may be some 7 years after the original filing of the patent application. During this passage of time, inventors inevitably move on from their original company, or become estranged and uncooperative.

Thus, the ability to get a supplemental declaration in a broadening patent reissue application can be a logistical nightmare. For this reason it is especially important to identify oath problems at the earliest possible point in patent reissue prosecution.

This week the inefficiency in correcting oath problems in a broadening patent reissues was demonstrated in Ex Parte Thomas Budmiger. In their decision, the Board explained:

[T]he Appellant argues, that the statement “I disclosed but did not claim the subject matter now included in claims 20-45” in the reissue declaration is sufficient. Brief 5.  Appellant reasons this is sufficient as method claim 20 is broader than claim 1 as it has four (4) steps where as method claim 1 has seven (7) steps. Brief 5. In response the Examiner cites to MPEP § 1414 and finds that the statement in the declaration fails to identify one distinguishing feature of the newly added claim over the patented claim which necessitated either broadening or narrowing the  patented claim. Answer 3. Based upon this finding the Examiner concludes that the reason cited in the declaration is not sufficient enough for filing of a reissue application. Answer 3. We concur with the Examiner.

We note that MPEP § 1414 (II)(C) states “[a]ny error in the claims must be identified by reference to the specific claim(s) and the specific claim language wherein lies the error.” MPEP § 1414(II)(C) also states “[a] statement of  “. . . failure to include a claim directed to . . .” and then presenting a newly added claim, would not be considered [a] sufficient “error” statement because applicant has not pointed out what the other claims lacked that the newly added claim has, or vice versa. Such a statement would be no better than saying in the reissue oath or declaration that “this application is being filed to correct errors in the patent which may be noted from the change made by adding new claim 10. In both cases, the error has not been identified.” Further, we note Appellant’s argument directed to the number of method steps in claim 20 versus claim 1 is not persuasive. In as much as the argument is a statement about the differences in the claims, it is not in the declaration and does not identify specific claim limitations.

(emphasis added)

Rather than providing a more specific notice of deficiency (perhaps suggesting particular fixes to the Patentee), the examiner simply stated that the error was not sufficient….likely relaying the decision of some other Office supervisor. It is no wonder patent reissue takes forever.

Last week, an important question relating to broadening patent reissue practice was argued before the CAFC. (In re Staats).

At issue in Staats is a third reissue patent application of Apple Computer Patent 5,940,600. The third reissue patent application was a continuation that claimed priority back to the original reissue application. (the original reissue application being properly filed within two years of issuance of the ‘600 Patent). During prosecution of the third continuation the examiner rejected the claims under 35 U.S.C. 251 as presenting broadening claims outside of the two year window for broadening reissue. The examiner reasoned that the error in the original reissue filing was allegedly unrelated to the error presented for correction in the third filing.

An expanded panel of the BPAI affirmed the rejection (Ex Parte Staats) characterizing the issue in dispute as:

This is a case of first impression. Resolution of the case hinges on one fundamental question: Can a continuing reissue application broaden patented claims beyond the statutory two-year period in a manner unrelated to the broadening aspect that was identified within the two-year period? Put another way, is it enough under the law to merely present an intent to broaden that is limited to a particular aspect (e.g., a particular embodiment of the invention) within the two-year period, yet broaden in unforeseeable ways (e.g., pertaining to other embodiments) outside the two-year period?

In last year’s BPAI decision, the Board analyzed the statute based upon their understanding of the equitable principles underlying the two-year limitation provided by the statute. In doing so, the BPAI relied heavily on the aspect of foreseeabilityemphasized in case law addressing prosecution laches. In affirming the rejection, the BPAI surmised:

Since this broadening was completely unforeseeable by the public within the two-year statutory period, a circumstance that is undisputed, it runs counter to the public notice function underpinning § 251 and is therefore improper.

With respect to forseeability, the CAFC appeared to recognize the impracticability of the USPTO’s “forseeability” test during last week’s oral argument. The bulk of the discussion during oral argument (audio here) related to whether or not earlier CCPA precedent controlled. In this regard, In re Doll 419 F.2d 925, 928 (CCPA 1970) was discussed extensively, as well as some early Supreme Court cases pertaining to patent reissue. The Court did not appear to accept the argument that the earlier Supreme Court cases supported the argument of the USPTO ( 21:40) and questioned whether or not Doll was truly distinguishable from the present facts.

The solicitor pointed out that the patent reissue statute has a limited two year window for broadening as a matter of public policy. The solicitor reasoned that the 2 year limit serves to enhance public’s reliance on issued claim scope and protect the public. The Court did not appear persuaded by public policy considerations, noting the seemingly “one-off” nature of the current fact pattern. Nevertheless, the Solicitor warned that a reversal of the agency would encourage filers to seek creative errors to broaden claims until patent term was exhausted.

Of course, most practitioners avoid broadening patent reissue practice altogether by simply maintaining a pending, regular continuation applications. The notion that anyone would pursue broadening patent reissue as a matter of course ignores the significant pendency problems, as well as thorny recapture and intervening rights issues.

Assuming this case were affirmed, is there now grounds to argue for “claim scope laches” vis-a-vis regular patent application continuation practice?

Back in February I recounted the oral agument of In re Mostafazadeh. This case explored the degree to which a claim limitation added to distinguish over the prior art during original prosecution may be broadened during patent reissue. In patent reissue, Mostafazadeh sought an intermediate scope to the “circular attachment pad” limitation added to his claims during original prosecution. In the reissue claims, the terminology “circular” was removed. To justify this broadening, the Patentee argued that the claim was materially narrowed in “other respects.”

On appeal, the CAFC considered whether or not the “materially narrowed in other respects” aspect of the rule established in In re Clement, (MPEP 1412.02), must be related to the “critical limitation” (i.e., circular attachment pad) or whether the narrowing must relate to an “overlooked aspect,” such as an unclaimed species or embodiment as advanced by the USPTO.

In their affirmance of the USPTO. the CAFC characterized the BPAI analysis as “perplexing” and found their interpretation of “materially narrowing” as “contrary to our precedent.”

The CAFC decision (here) explained that the materially narrowing necessary to avoid recapture must relate to the surrendered subject matter, not an “overlooked aspect” of the invention as required by the USPTO, stating:

[A] limitation that is added during prosecution to overcome prior art cannot be entirely eliminated on reissue because doing so would constitute recapture of the surrendered subject matter. The limitation may be modified, however, so long as it continues to materially narrow the claim scope relative to the surrendered subject matter such that the surrendered subject matter is not entirely or substantially recaptured.     

 

 .           .           .           .           .           .           .

 

[T]he recapture rule is violated when a limitation added during prosecution is eliminated entirely, even if other narrowing limitations are added to the claim. If the added limitation is modified but not eliminated, the claims must be materially narrowed relative to the surrendered subject matter such that the surrendered subject matter is not entirely or substantially recaptured. (emphasis added)

Mostafazadeh did not eliminate the attachment pad limitation, only modified it by removing “circular.” Still, the Board found that the narrowing limitations added in the patent reissue did not relate to the attachment pad limitation, thus step (3) of the Clement test could not save the Patentee. Had the Patentee added narrowing language that related to the circular pads, such as requiring that the attachment pads be formed of a specific alloy, or oriented in a certain way, the removal of “circular” may have been acceptable.

This case, much like In re Tanaka, will provide Patentees a greater degree of flexibility, and opportunity to pursue patent reissue going forward.

The three step analysis of In re Clement is as follows:

(1) first, we determine whether, and in what respect, the reissue claims are broader in scope than the original patent claims; 

(2) next, we determine whether the broader aspects of the reissue claims relate to subject matter surrendered in the original prosecution; and

(3) finally, we determine whether the reissue claims were materially narrowed in other respects, so that the claims may not have been enlarged, and hence avoid the recapture rule. (emphasis added)

In considering the case, the CAFC found both the MPEP discussion of step (3) and BPAI decision on this point to be confusing. {14.50 min mark}

During original prosecution, the Patentee cancelled claims to a semiconductor package having leads and a bus bar. To overcome art showing a package having leads and a bus bar, these claims were cancelled in favor of claims directed to a semiconductor package having circular pads. In their patent reissue application, the circular pad feature was removed, and the claims cancelled during original prosecution were re-presented, with the bus bar feature now requiring exposure at the bottom of the package. Due to the removal of the circular pad feature steps (1) and (2) of the recapture test were seemingly satisfied.

With respect to step (3) the Patentee argued that the new reissue claims required bus bars that were exposed at the bottom of the package, and thus materially narrowed relative to the cancelled claims (i.e., surrendered subject matter). In essence, the Patentee argued that the claim scope surrendered was limited to the scope of the cancelled claims only, and not an intermediate scope that would have otherwise been available. (such as a package with exposed bus bars).

The PTO argued that the “other respects” aspect of step (3) cannot relate to the disavowed element (bus bars), but instead the broadening (removal of circular pads). The PTO cited the following example of the MPEP to illustrate their point:

Assume that, in the original prosecution of the patent, applicant claimed a method of making a glass lens, where the ion implantation step used a molten bath to diffuse ions into the lens, and that step had to be amended to recite a pressure of 50-60 PSI and temperature between 150-200 degrees C – to define over the art. That pressure and temperature range-set is “frozen” in place for any molten bath ion implantation claim, and it cannot be deleted or broadened by reissue. However, if in the original application, applicant had failed to claim a disclosed embodiment to plasma ion implantation (i.e., using a plasma stream rather than a molten bath to provide the ions), that is a proper 35 U.S.C. 251 error, which can be corrected by reissue. Applicant can, in a reissue application, add a set of claims to plasma ion implantation, without including the “50-60 PSI and temperature between 150-200 degrees C” limitation. The “50-60 PSI – 150-200 degrees C limitation” is totally irrelevant to plasma implantation and is clearly wrong for the plasma species/embodiment, as opposed to being right for the molten bath species/embodiment.

At the close of the argument, the CAFC seemed to understand the MPEP. However, both the solicitor and the judges agreed that the explanation in the MPEP was imprecise. The solicitor indicated that the discussion of step (3) would greatly benefit from the decision in this case. {25.30 min. mark}.

Stay tuned.

As shown in the charts above (click to enlarge images), we analyzed the 745 broadening patent reissues filed since 2005. A surprising 200 applications of the 745 were ultimately abandoned. While many of these applications may have been seeking to secure a claim scope that was precluded by prior art, it may also be that a significant number fell victim to the frustrations of reissue practice. The lowermost chart above factors out abandonments as a true conclusion, demonstrating that only 20% of broadened reissues are concluded within 3 years of filing. When compared to the special dispatch accorded to patent reexamination, these important applications clearly fare a great deal worse.

The data for narrowing reissues shows slightly better  timeliness, perhaps due to the absence of recapture doctrine concerns. Data for narrowing reissues will be posted in the coming days.

I understand the PTO is considering creating a special unit for patent reissues, much like was done for patent reexamination. My guess is more reissue would be filed should these applications be treated with the importance they deserve.

If anything, the pendency problems plaguing patent reissue demonstrate the value of maintaining pending continuation applications.

Comparing Claims in Reissue Oath Haunts Patent Holder

On Wednesday, the Federal Circuit reversed a decision of the ITC that excluded the imports of Lucky Litter, LLC. The case (here) related to cat litter boxes having an automated cleaning feature. In reversing the ITC, the CAFC found that the “predetermined event” recited in claim 33 of the patent at issue (RE 36,847), was not limited to a cat exiting the litter box.

Prior to seeking patent reissue, claim 1 of the patent recited a “cat exit sensor for sensing a cat exit” and a “delay means.” The Patentee filed a broadening patent reissue to remove these features. The reissue application oath explained that “[i]n particular, claim 1 of U.S. Patent 5,477,812 contains recitations regarding a cat exit sensor and delay means which are too limiting of the invention and unnecessary in view of the prior art. Claims 23 through 48 of the reissue application have limitations similar to those of claim 1, but define the invention with greater breadth.”

The CAFC performed a traditional Phillips analysis of the ITC claim construction and held that “predetermined event,” by plain meaning, could not be limited to “cat exit.”  Still, the statement in the oath was cited by the court as a guidepost of the broader meaning of the claims added in reissue. Hindsight always being 20/20, what could the Patentee have done to potentially avoid this result?

Claim construction issues aside, recent BPAI cases illustrate the importance of oaths in patent reissue. All too often, the preparation of the oath is deemed ministerial, and ignored in favor of prior art/claim drafting concerns. Oath preparation and wording should be a focal point of any patent reissue effort.

When identifying an error in an original patent via added/amended claims in patent reissue, comparison to the originally issued claims is very attractive. This practice is not necessarily wrong, but can have unintended consequences as demonstrated by Lucky. By making such direct comparisons, the scope of the newly added claims becomes unnecessarily intertwined with the issued claims. For example, the oath in Lucky Litter would have been better off stating “new claims 23 through 48 are directed to the automated comb operation of a self cleaning cat litter box, albeit independent of any specific sensor or means-plus-function structure of the issued claims.” (I know, easy for me to say 10 years after the fact)

It may be that the Patentee in Lucky still would have lost, oath or not. Nevertheless, the case demonstrates that oath filings are far from form practice, and can come back to haunt Patentees.  Finally, the patent is subject to an ongoing ex parte reexamination (90/010,389) and, as you may have guessed, new claims were added expressly reciting “cat exit.”  (see new claim 54).

Patent reissue has been a recurring topic here as of late. More recently, the breadth of the recapture doctrine has been discussed. Earlier this year, I discussed ex parte Staats relative to a pending CAFC appeal, and the pending CAFC appeal of ex parte Tanaka.

While the main issue in ex parte Tanaka is whether or not the addition of narrower dependent claims via patent reissue can be said to correct an “error” pursuant to the reissue statute, Tanaka, to a lesser extent, also illustrates the danger of a generically worded reissue declaration. As the BPAI decision of last Friday once again emphasizes, (ex parte Matthew Howard Fronk et al.,) a proper broadening declaration must not only identify at least one error in the issued patent (made without deceptive intent), but must also unequivocally indicate an intention to broaden. More importantly, this unequivocal intent to broaden must be communicated to the USPTO by declaration only, within two years of original patent issuance.

When prosecuting reissue patent applications, defective declarations are the norm due to the USPTO’s heightened interest in ensuring the declaration specifically identify the error sought to be corrected. Further, when presenting a broadening reissue, it is not uncommon for such an application to be filed very close to, or on the date of the two year anniversary of original patent issuance. When filing such “last minute” broadening reissue applications, failure to identify an unequivocal intent to broaden could be fatal.

In deciding a case last Friday the BPAI shot down an ambiguously worded declaration that attempted to cover both narrowing and broadening, explaining:

In the instant case, we cannot agree with Appellants’ contentions that the statement “by reason of a patentee claiming more or less than he had a right to claim in the patent” in the Reissue Application Declaration is a clear statement of intent to file a broadening reissue application. . . . .(emphasis added)

In the present case, Appellants’ description fails to indicate that the reissue is a broadening reissue and does not explain the nature of the broadening. . . .  Accordingly, Appellants’ argument that the Examiner was required to make findings that intent may be inferred from the reissue application declaration is not well taken. (App. Br. 8-9.) Appellants’ belated explanation of why the amendment to claim 1 broadens the claims of the ‘376 Patent in the preliminary amendment of October 20, 2004 and in the Appeal Brief (FF 6; App. Br. 11) are insufficient to rectify the deficiencies of the Reissue Application Declaration. Arguments of counsel cannot take the place of or supplement the Reissue Application Declaration. Oetiker, 1997 WL 1883795 at *5-6. Therefore, the Examiner did not err in rejecting claims 9-172 under 35 U.S.C. §251 as being directed to a broadening reissue improperly filed after two years from the issue date of the ‘376 Patent.

Clearly, the USPTO considers a broadening declaration proper ONLY when unequivocal, and presented within two years of original patent issuance.

As recent cases demonstrate, the nuances of patent reissue practice are significant and largely underappreciated by Patentees.

The recapture doctrine of patent reissue is often a subject of debate before the BPAI. As we discussed last week, the question of the propriety of an intermediate claims scope vis-a-vis recapture was recently decided by the BPAI, and briefing before the CAFC is near complete on the same issue (In re Mostafazadeh). A day after the BPAI decision of last week, the Federal District Court of Ohio considered recapture in the context of statements made outside of the USPTO in Bendix Commercial Vehicle Systems LLC, et al v. Haldex Brake Products Corp., 1-09-cv-00176 (N.D.O.H)

As a reminder, the recapture doctrine exists because a deliberate surrender of subject matter is not an “error” that is correctable by patent reissue. The recapture doctrine prevents Patent Holders from broadening claim scope in patent reissue that was deliberately surrendered during original prosecution. In Bendix, the defendant (Haldex) argued that the asserted broadened reissue patent, RE 38,874, (relating to automotive braking equipment) was invalid under 35 USC § 251 due to statements made during an earlier litigation and in a foreign patent office.

As one would expect, the defendant also argued traditional disclaimer/estoppel theories along with recapture, to no avail.

The recapture argument was the continuation of an earlier effort. During the patent reissue proceeding, the defendant filed a protest pointing out the alleged recapture issue to the USPTO, but the examiner sided with the Patent Holder explaining that [n]o rejection of the claims over the prior art of record was made in the application and therefore no arguments were made to distinguish the claims from the prior art of record.

Essentially siding with the earlier examiner’s position, the district court explained (decision here):

Haldex also points to statements made after the issuance of the original patent, during a prior litigation over that patent, claiming that these statements constitute the surrender of claims relating to anything other than a one-piece caliper. Acceptance of this argument would require an extension of the current law governing the recapture rule. Federal Circuit case law clearly holds that a surrender, for purposes of the recapture rule, can only be made through arguments, statements, and amendments made during the prosecution of the original patent. See, e.g., Hester Indust, Inc. v.Stein, Inc., 142 F.3d 1472, 1480 (Fed. Cir. 1998)(citing In Re Clement, 131 F.3d 1464, 1469 (Fed.Cir. 1997)(“To determine whether an applicant surrendered particular subject matter, we look to the prosecution history for arguments and changes to the claims made in an effort to overcome a prior art rejection.”).

PPG Comment: With respect to litigation statements, this decision is not at all surprising. Recapture answers the simple question of whether or not a surrender of claim scope was deliberate BEFORE patent issuance. (i.e., not a correctable “error” that can be corrected LATER by patent reissue). Since the error can only have happened before issuance, it follows that factors considered in a recapture analysis are also limited to pre-issuance conduct.

On the other hand, the court was able to dodge the more interesting foreign prosecution question. The defendants identified alleged surrender of claim scope based on statements made in the prosecution of the German priority application (occurring before the U.S. prosecution). The court was able to side step this issue based on the fact that different U.S. claims were introduced by preliminary amendment at the time of U.S. filing. (also noting that the appropriate PCT form box was NOT checked carrying over amendments from the earlier, German prosecution).

Aside from a 112 rejection (non-prior art), the U.S. application was allowed without discussion of prior art. What if the claims had remained the same, recapture?

Earlier this year we discussed the Ex Parte Tanaka decision of the Board of Patent Appeals & Interferences (BPAI) with respect to “bullet claims”  in patent reissue, now before the CAFC. On June 24, 2010, a second Board decision relating to patent reissue was appealed to the Federal Circuit (Ex Parte Staats).

Although presented in the context of patent reissue, the point of contention in Staats is actually one of prosecution laches and the application of equitable principles to statutory interpretation. In Staats, the Board upheld a rejection of a broadening reissue application as defective under 35 U.S.C. 251 for failing to include the appropriate broadening oath within two years of the original patent issuance. The Board reasoned that although a parent reissue had filed an appropriate broadening oath and identified at least one error, the continuation reissue was not entitled to rely on that oath, despite the continuity between these reissue applications. The BPAI presented the issue as :

This is a case of first impression. Resolution of the case hinges on one fundamental question: Can a continuing reissue application broaden patented claims beyond the statutory two-year period in a manner unrelated to the broadening aspect that was identified within the two-year period? Put another way, is it enough under the law to merely present an intent to broaden that is limited to a particular aspect (e.g., a particular embodiment of the invention) within the two-year period, yet broaden in unforeseeable ways (e.g., pertaining to other embodiments) outside the two-year period?

While the Board noted that the question of interpreting 35 U.S.C. 251 in this manner was a case of first impression, MPEP 1412.03 (IV) was argued by Apple as directly on point (i.e., explicitly authorizing the practice). Curiously, the Board found this aspect of the MPEP ambiguous, and analyzed the statute based upon their understanding of the equitable principles behind the two-year limitation provided by the statute.

In doing so, the BPAI relied heavily on the aspect of foreseeability emphasized in case law addressing prosecution laches. In affirming the rejection, the BPAI surmised:

Since this broadening was completely unforeseeable by the public within the two-year statutory period-a circumstance that is undisputed-it runs counter to the public notice function underpinning § 251 and is therefore improper.

In arriving at their conclusion on equitable principles, the BPAI reviewed the seminal cases in this area (In re Graff, 111 F.3d 874, 877, 42 USPQ2d 1471, 1473-74 (Fed. Cir. 1997) and (In re Doll, 419 F.2d 925, 928, 164 USPQ 218, 220 (CCPA 1970). The Board noted that both of these early decisions supported their conclusion that the manner of broadening must be identified within two years.

Arguably, neither of these cases needed to consider the manner of the broadening. Thus, the Board noted only that the facts of Doll were consistent with their decision, and Graff emphasized the two year requirement. So, to buttress their decision, the Board relied on case law relating to prosecution laches, such as Symbol Techs., Inc. v. Lemelson Med., Educ. & Res. Found., 277 F.3d 1361, 1364 (Fed. Cir. 2002).

However, the cases dealing with foreseeability in the prosecution laches context relate to applications that were prosecuted in secret (i.e., before the days of publication). As reissue applications are published in the Official Gazette, foreseeability with respect to specific changes is only a mouse click away via PAIR. Certainly, in the past, there was significant motivation to purposely delay prosecution in the days of  “submarine applications.”  However, by waiting 8 years to file the continuation reissue application in question, Apple only surrendered enforceable patent term to the public (intervening rights).

There is little motivation for anyone to drag their feet in reissue, likewise, the manner of broadening is not the least bit secret. Interested parties cannot not only track the progress of such broadening publicly, but are provided a mechanism to protest via the submission of prior art under 37 CFR 1.291.

Should be an interesting CAFC opinion, stay tuned.

Patent owners seeking reissue within two years of patent issuance are permitted the additional opportunity to broaden the issued claims, subject to intervening rights. Reissue applications filed outside this two year window may not broaden issued claim scope.

Although patent reissue allows for the correction of mistakes in claim scope, the proceeding is not a “do-over” of the original prosecution.  Important limits are placed on patent reissue with respect to the scope of claim changes. For example, a patent owner may not surrender claims scope during the original application prosecution, then seek to recover this same scope via reissue. The prohibition against this practice is known as the recapture doctrine (an earlier post on this topic is found here)

Other prohibitions less commonly appreciated relate to the types of claims that may form the basis of the reissue application.

Ex Parte Tanaka, decided last December by the Board of Patent Appeals and Interferences (BPAI), (now on appeal to the CAFC) held that a reissue application was improper where the only defect identified in an issued patent was the failure to present additional dependent claims.  The Board reasoned that the mere addition of new dependent claims did not identify any defect in the issued patent.

This same reasoning is also utilized in another under appreciated aspect of reissue application practice, namely the pursuit of non-elected claims.  In other words, if claims are restricted during original prosecution of the application, and those claims are not pursued in a divisional application, such claims cannot be obtained by patent reissue (very limited exceptions for linking claims in a genus/species sense). For example, let us assume that in prosecuting your original application method claims are elected and pursued. Restricted apparatus claims are canceled, and a divisional application is not filed to pursue the non-elected apparatus claims. In such a case, based on current USPTO and CAFC interpretation of 35 U.S.C. § 251 the apparatus claims are lost (MPEP 1412.01).

Of course, a broadening reissue could be pursued to enlarge claim scope to recover claims that were not canceled based on the prior art (i.e., no recapture)  Yet, when attempting to add canceled, non-elected claims, the error is not a defect in the issued patent. Instead, this defect is one of portfolio management; simply stated, the issued patent is operative for the method claims.

With Ex Parte Tanaka on appeal to the CAFC, perhaps the statute will be revisited and defined more liberally by the court to embrace errors in prosecution having a wider impact on patent portfolios. Until such time, practitioners should recognize that patent reissue is a tool to correct mistakes of an issued patent, not a tool to resurrect disregarded claims of the original prosecution.