Opinion for the court filed by Circuit Judge SCHALL. Concurring-in-part and dissenting-in-part opinion filed by Circuit Judge DYK.
SCHALL, Circuit Judge.
This is a patent case. Medtronic, Inc. ("Medtronic") is a manufacturer of medical devices. It filed a declaratory judgment action in the United States District Court for the District of Delaware against Guidant Corporation, Guidant Sales Corporation, Eli Lilly & Company ("Eli Lilly"), and Mirowski Family Ventures L.L.C. In the action, Medtronic alleged that claims 15-26 of U.S. Reissue Patent No. 38,119 ("the RE'119 patent"), a re-issue of U.S. Patent No. 4,928,688 ("the '688 patent"), are invalid by reason of violation of the rule against recapturing surrendered subject matter. The RE'119 patent claims a method and a pacemaker apparatus. Both relate to a "procedure for pacing of the heart in a particular way so as to improve its contraction pattern, and thereby augment the movement of blood through the heart." RE'119 patent, col. 3, ll. 33-35. Mirowski Family Ventures L.L.C. and Eli Lilly are, respectively, the assignee and exclusive licensee of the patent. Guidant Corporation is a medical device manufacturer that was formed in 1994 when Eli Lilly divested certain assets, while Guidant Sales Corporation is a wholly owned subsidiary of Guidant Corporation. For ease of reference, we refer to the four defendants as "Guidant."
Medtronic now appeals from the final judgment of the district court, following a bench trial, that the RE'119 patent is not invalid.
The heart is made up of four chambers: two atria and two ventricles. Electrical stimulations (depolarizations) within the chambers cause contractions within the heart that result in pumping. The electrical activity arises in the right atrium and is eventually transmitted to the ventricles. The period of time from depolarization of the atria to depolarization of the ventricles is called the "A-V delay period."
Dr. Morton Mower is the inventor named on the RE'119 patent. His invention involves a method and apparatus for treating ventricular asynchrony, a condition in which a person has a defect in his or her heart ventricles. The defect causes the ventricles to contract at different times. This results in the loss of effectiveness in the pumping of blood. The method of the RE'119 patent works through a pacemaker device invented by Dr. Mower which either conditionally or unconditionally paces the two ventricles of the heart to cause simultaneous ventricular contractions. The "conditional embodiment" of the invention requires sensing a depolarization in a first ventricle, then waiting for a predetermined period of time to sense a depolarization in the second ventricle. If no depolarization is sensed in the second ventricle, the device stimulates, or "paces" the second ventricle with an electrical pulse. This embodiment of the invention is called "conditional" because the delivery of pacing pulses depends on the analysis of the cardiac signals. In the "unconditional embodiment," depolarization is sensed in either ventricle and, as soon as depolarization in one ventricle is sensed, both ventricles are immediately paced. In the "unconditional embodiment," one ventricle will be paced twice, once naturally and once by the device.
In the invention's conditional embodiment, there are two apparatuses to sense electrical activity ("sensing electrodes"). There is one sensing electrode in each ventricle. In addition, there is at least one pacing electrode to pace the second ventricle. In the unconditional embodiment, there may be only one sensing electrode, as once a depolarization is sensed in one ventricle, the other ventricle is immediately paced. However, there are always two pacing electrodes, so that both ventricles may be paced at the same time.
In the late 1980s, Dr. Mower asked Ron Cohn to prepare a patent application for his invention. On October 30, 1987, Cardiac Pacemakers, Inc. (now a wholly owned subsidiary of Guidant Corporation), where Dr. Mower was employed, forwarded Mr. Cohn's draft application to attorney Thomas Nikolai to prepare a final application. On December 3, 1987, Mr. Nikolai asked Dr. Mower to review the draft application, explaining that he had added the concept of a "window of coincidence"—a delay between sensing and pacing.
On August 23, 1988, Mr. Cohn, pursuant to instructions from Dr. Mower, forwarded Dr. Mower's comments to Mr. Nikolai, advising him that the essence of Dr. Mower's invention was "a bi-ventricular pacer [that] continually senses the activity of both the left and right ventricles, and when activity is sensed in either ventricle the device immediately electrically paces the other or both ventricles." With respect to Mr. Nikolai's concern about a "window of coincidence," Mr. Cohn stated that to have a delay between sensing and pacing would undermine the purpose of the invention, which he said was to cause a simultaneous contraction of the ventricles. On August 31, 1988, Mr. Nikolai responded to Mr. Cohn's letter with a letter to Dr. Mower, stating that he was "puzzled" about how the invention could sense the depolarization of one ventricle and then decide whether to pace the other ventricle without a delay period.
On September 9, 1988, Dr. Mower explained to Mr. Nikolai that while the mechanism would in some cases stimulate a ventricle that was in fact contracting normally, that was not a problem because "the artificial stimulus will fall harmlessly into the intrinsic depolarization." Mr. Nikolai then amended the specification to include a description of the unconditional embodiment.
On January 23, 1989, U.S. Patent Application No. 07/299,895 ("the '895 application") was filed with the Patent and Trademark Office for Dr. Mower's invention. As filed, the '895 application had twenty-two claims, including six independent claims (claims 1, 7, 15-17, and 19). Pertinent to this case, claims 1, 7, 15, and 16 of the '895 application stated:
The specification included the following language directed towards the unconditional embodiment:
On June 9, 1989, the examiner issued a first office action, allowing claims 15 and 16 but rejecting the remaining twenty claims. Independent claims 1 and 7 and dependent claims 4-6 and 12-14 were rejected as anticipated by U.S. Patent No. 4,378,020 ("Nappholz"). The examiner asserted that Nappholz showed "all of the structure of the above claims." At the same time, the examiner rejected dependent claims 2, 3, 8, and 9 as obvious in view of Nappholz and U.S. Patent No. 4,774,950 ("Cohen"). The examiner asserted that Cohen showed "a means to sense a cardiac signal from the left or right ventricles. It is deemed to have been obvious to use Cohen with the pacemaker in Nappholz et al in order to more efficiently and effectively pace and sense the heart." The examiner explained, however, that "[t]he prior art does not show means to sense and stimulate both ventricles in a selective or alternate manner." The examiner suggested that dependent claims 10 and 11 and independent claims 17 and 19, as well as dependent claims 18 and 20-22, would be allowed if their form was corrected.
Mr. Nikolai responded on June 16, 1989, by canceling claim 6, by adding several claims, and by amending certain claims. Mr. Nikolai added independent claim 23 and dependent claims 24-27, all directed to the pacemaker apparatus. At the same time, he amended limitation (c) of claim 1 to read as follows: "providing electrical pulses from a stimulating circuit controlled by said control circuit
(Emphasis in original).
(Emphasis in original).
The examiner responded on September 6, 1989, allowing dependent claims 4 and 15-22, but rejecting all other pending claims. Claims 1-3 and 5 were rejected as obvious in view of U.S. Patent No. 4,088,140 ("Rockland") on the ground that the method of claims 1-3 and 5 would be "within the scope of the skilled artisan when utilizing the Rockland . . . invention." Claims 7-9 and 12-14 were rejected as anticipated in view of Rockland on the ground that "Rockland . . . shows all of the basic structure of the above claims." Claims 10, 23, and 25-27 were rejected as being obvious in view of Rockland and U.S. Patent No. 3,937,226 ("Funke") because it would be "an obvious engineering design choice . . . to connect the ventricular electrodes in series, as shown by Funke." Finally, claims 11 and 24 were rejected as being obvious in view of Rockland and Funke and further in view of an additional patent ("McCorkle") because "[i]t would have been obvious to one of ordinary skill in the art to use McCorkle with Rockland et al and Funke in order to more efficiently and accurately pace/sense ventricular depolarizations."
Mr. Nikolai responded by amending certain claims and canceling claims 4, 7-14, and 25-27. He amended claim 1 to add the following to limitation (c) of the claim:
Mr. Nikolai contended that, after this amendment, claim 1 and claims 2, 3, and 5, which depended directly or indirectly from claim 1, were allowable. Mr. Nikolai argued that claim 23 was not obvious in light of Rockland and Funke because Rockland failed "to disclose a pacer apparatus having circuitry for analyzing cardiac signals originating in the right and left ventricles for selectively providing stimulating or pacing pulses only to the right ventricle if a normal cardiac signal is missing there or to the left ventricle if the left ventricle is not producing normal heart activity in the left ventricle." Because claim 24 depended from claim 23, Mr. Nikolai asserted that it too was not obvious.
On December 5, 1989, the examiner and Mr. Nikolai conducted a telephone interview. After the interview, the examiner made an examiner's amendment for "minor wording changes" to put claims 15, 16, and other claims "in condition for allowance." The Notice of Allowability issued on December 11, 1989. After the amendment, claims 15 and 16 of the '895 application read as follows:
(Examiner's amendment emphasized). As can be seen, whereas before the examiner's amendment claims 15 and 16 claimed Dr. Mower's unconditional embodiment, after the amendment they claimed only the conditional embodiment.
On May 29, 1990, the '688 patent issued to Dr. Mower. Claims 1-3, 5, and 15-24 of the '895 application issued as, respectively, claims 1-14 in the '688 patent.
On May 29, 1992, pursuant to 35 U.S.C. § 251, Mr. Cohn, on behalf of Dr. Mower, sought reissue of the '688 patent with existing claims 1-14 and new claims 15-24. Claims 15-24 of the application were directed to the unconditional embodiment. Dr. Mower's reissue declaration stated that he had "claimed less than [he] had a right to claim in the patent" as the claims inadvertently did not include the unconditional embodiment.
On April 8, 1993, the examiner rejected all claims in the reissue application. The examiner rejected new claims 15-24 pursuant to 35 U.S.C. § 112, first paragraph, stating that the specification did not support the invention. He explained that in the specification, "it is mentioned that both ventricles are immediately stimulated," but in claims 15-24, "it is claimed that one
Mr. Cohn amended claims 15, 16, 19, and 20 to more explicitly claim the unconditional embodiment and argued that the specification did describe the invention. The examiner then allowed reissue claims 1-18 and 20-24, but rejected claim 19. The examiner asserted that claim 19 was obvious in light of U.S. Patent No. 4,624,260 ("Baker") and Rockland and obvious in light of Baker and Funke. Mr. Cohn responded by arguing that claim 19 was not obvious in light of the prior art because neither Baker nor Rockland taught pacing in both ventricles followed by an A-V delay period. He also added two claims, claims 25 and 26, to distinguish Baker, Rockland, and Funke.
The RE'119 patent issued on May 20, 2003. The RE'119 patent has 26 claims. Claims 1-14 of the RE'119 patent are identical to claims 1-14 of the '688 patent. Of the remaining claims (which are new), claims 15, 19, 22, and 25 are independent.
On August 29, 2003, Medtronic filed a declaratory judgment action against Guidant, alleging that claims 15-26 of the RE'119 patent are invalid because the unconditional embodiment and the embodiment with only one sensing electrode were improperly recaptured. The unconditional embodiment appears in claims 15-26. Claim 15 of the RE'119 patent is representative. It states:
RE'119 patent, claim 15. The embodiment requiring only one sensing electrode appears in at least claims 15, 16, 25, and 26 of the RE'119 patent.
Medtronic urged that both the unconditional embodiment and the embodiment with only one sensing electrode were recaptured because they were claimed in the original claims and amended during prosecution, or they were surrendered via argument during prosecution. Specifically, Medtronic asserted that claims 1, 7, 15, and 16 of the '895 application cover the unconditional embodiment, but were amended to cover only the conditional embodiment. As far as the embodiment with one sensing electrode was concerned, Medtronic argued that the embodiment, which it asserted appears in claims 15-18 and 22-26 of the RE'119 patent, was surrendered during prosecution.
In November 2004, the district court held a three-day bench trial. Medtronic argued that there was no error during the prosecution of the '895 application that would justify reissuing the patent under 35 U.S.C. § 251. Guidant responded that the error was attorney error resulting from Mr. Nikolai's failure to understand the technology.
In its decision rendered after trial, the district court ruled that the RE'119 patent did not improperly recapture subject matter that was surrendered during prosecution.
The court first determined that the unconditional embodiment was not surrendered by amendment.
The court next found that the unconditional embodiment was not surrendered by argument.
The court also found that the embodiment with only one sensing electrode— specifically, the embodiment represented by claim 15 of the RE'119 patent—was not surrendered during prosecution by amendment.
Finally, the district court determined that the embodiment with only one sensing electrode, which is claimed in claim 15 of the RE'119 patent, was not surrendered by argument.
After judgment was entered, Medtronic filed a timely notice of appeal. We have jurisdiction pursuant to 28 U.S.C. § 1295(a)(1).
Pursuant to 35 U.S.C. § 251, a patentee may obtain reissue of a patent if the patent is, through error "without any deceptive intention, deemed wholly or partly inoperative or invalid, . . . by reason of the patentee claiming more or less than he had a right to claim in the patent. . . ." 35 U.S.C. § 251;
Reissue proceedings, however, cannot be used to obtain subject matter that could not have been included in the original patent. Under the "recapture" rule, the deliberate surrender of a claim to certain subject matter during the original prosecution of the application for a patent "made in an effort to overcome a prior art rejection" is not such "error" as will allow the patentee to recapture that subject matter in a reissue.
A surrender can occur by argument as well as by amendment.
"We apply the recapture rule as a three-step process: (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."
Determining whether the claims of a reissued patent violate 35 U.S.C. § 251 is a question of law, which we review de novo.
Medtronic contends first that claims 15 through 26 of the RE'119 patent are invalid because they recapture the unconditional embodiment. Medtronic asserts that this embodiment was surrendered both by amendment and by argument during prosecution of the '895 application.
Medtronic argues that claims 1, 7, 15, and 16 of the '895 application, as filed, covered the unconditional embodiment and that, during prosecution, their scope was limited to the conditional embodiment. It argues that claims 15 through 26 of the RE'119 patent improperly recapture the unconditional embodiment. Guidant responds that the recapture rule does not apply to claims 15-26 of the RE'119 patent because, as filed, claims 1, 7, 15, and 16 of the '895 application were directed to the conditional embodiment. It urges that the district court correctly held that the unconditional embodiment was not surrendered by amendment.
The first issue is whether the claims at issue, in this case claims 1, 7, 15, and 16 of the '895 application,
"Whether amendments made during reexamination enlarge the scope of a claim is a matter of claim construction."
We agree with the district court and Guidant that independent claims 1 and 7 of the '895 application as filed, and the claims that depended from them, claims 2-6 and 8-14, did not disclose the unconditional embodiment.
We agree with the district court and Medtronic that claims 15 and 16 of the '895 application as filed did include the unconditional embodiment. Claims 15 and 16 of the '895 application as filed disclosed a method for effecting simultaneous contraction of both left and right ventricles. In claim 15, one step was "stimulating at least one ventricle substantially simultaneously with the contraction of at least one other ventricle." Claim 15 clearly covered the unconditional embodiment because it immediately paced. In claim 16 as filed, one step was "stimulating at least one ventricle simultaneously with the contraction of at least one other ventricle after a predetermined A-V period." While there was a delay in claim 16, there was no analysis step. Both claims described a device that paces at least one ventricle after the contraction of at least one ventricle, so the claims as filed were directed to a device that immediately paces the ventricles—i.e., the unconditional embodiment.
Because claims 15 and 16 did include the unconditional embodiment, we must consider whether the unconditional embodiment was surrendered during prosecution. We agree with the district court and Medtronic that after the examiner's amendment— characterized as making "minor wording changes"—claims 15 and 16 no longer covered the unconditional embodiment. After the examiner's amendment, claim 15 of the '895 application as issued (claim 5 in the '688 patent) had the additional limitations of
While claims 15 and 16 of the '895 application did cover the unconditional embodiment as filed, and while they were amended so that they no longer covered that embodiment, that alone does not mean that the unconditional embodiment was surrendered. This court has recognized that whether recapture applies "'necessarily depends upon the facts in each case and particularly on the reasons for the cancellation.'"
In this case, there was no deliberate surrender of subject matter to obtain allowance of the claims. As discussed above, an attorney's failure to appreciate the full scope of the invention is a common source of defects in patents and has been found to be sufficient to justify reissuing a patent.
Further, there is no evidence that the unconditional embodiment could not have been included in the original patent. There is also no evidence that the unconditional embodiment was deliberately surrendered in an effort to overcome a prior art rejection. In fact, there was no prior art rejection, or any rejection at all. Thus, the examiner's amendment was not prompted by a rejection. We agree with the district court that because claims 15 and 16 were not amended over prior art, and because the amendments to the claims were made as clarifying amendments, there was no clear admission that the unconditional embodiment was not patentable. For this reason, the reissue rule does not apply with respect to these claims.
Thus, we agree with the district court that claims 15 through 26 of the RE'119 patent are not invalid for recapturing the unconditional embodiment by amendment.
Medtronic also argues that the unconditional embodiment in claims 15-26 of the RE'119 patent was surrendered by argument. Guidant responds that Medtronic has not shown a clear and unmistakable surrender as
We agree with the district court that Dr. Mower did not surrender the unconditional embodiment through arguments made during prosecution. Mr. Nikolai distinguished claims 1 and 7 of the '895 application, and their dependent claims, which were directed to the conditional embodiment, on the ground that Nappholz only disclosed a single atrial electrode and a single ventricular electrode and thus was unable to sense and pace both ventricles, which is what is claimed in claims 15 and 16 of the RE'119 patent. Thus, Mr. Nikolai did not distinguish Nappholz one the grounds that Nappholz immediately and unconditionally paced both ventricles.
Mr. Nikolai also distinguished the rejected dependent claims 2, 3, 8, and 9 of the '895 application, which were directed to the conditional embodiment, from Cohen on the ground that Cohen had electrodes in the ventricles that paced but did not sense. In the unconditional embodiment in claims 15-26 of the RE'119 patent, however, there is at lease one sensing electrode in a ventricle. Thus, Mr. Nikolai did not clearly and unmistakably surrender the unconditional embodiment.
Medtronic also points to the arguments made by Mr. Nikolai with respect to rejected claim 23 of the '895 application in support of its argument that the unconditional embodiment was surrendered by amendment. Mr. Nikolai distinguished Rockland because it could not selectively analyze and, instead, described a device that paced over a predetermined time interval. The unconditional embodiment, on the other hand, may immediately pace after a depolarization is sensed in one ventricle. Thus, Mr. Nikolai did not clearly and unmistakably surrender the unconditional embodiment.
Thus, we agree with the district court that claims 15 through 26 of the RE'119 patent are not invalid for recapturing the unconditional embodiment by argument.
Medtronic argues that claims 15, 16, and 22-26 of the RE'119 patent are invalid because they recapture the embodiment with only one sensing electrode. According to Medtronic, this embodiment was surrendered by amendment and argument during prosecution of the '895 application.
Medtronic asserts that claim 7 of the '895 application as filed covered sensing in a single ventricle as well as sensing in both ventricles, and was amended to surrender sensing in only one ventricle. According to Medtronic, claim 7 covered sensing in a single ventricle because the term "ventricular sensing means" encompassed sensing in either one ventricle or in both ventricles. Second, it asserts that claims 15, 16, and 22-26 of the RE'119 patent improperly recapture the embodiment with only one sensing electrode that was surrendered during prosecution. Guidant responds that the district court correctly held that the embodiment with only one sensing electrode was not surrendered by amendment because original claim 7 required sensing from both ventricles and Medtronic's arguments do not apply to reissue claims 22-24 because they require sensing from both ventricles.
The first issue we must address is whether claim 7 of the '895 application ever disclosed the "sensing of electrical activity in only one ventricle" embodiment.
We agree with the district court that claim 7 in the '895 application as filed did not include an embodiment with only one sensing electrode. Medtronic is incorrect that claim 7 of the '895 application as filed covered sensing in a single ventricle as well as sensing in both ventricles. The claim refers to a "bi-ventricular pacemaker," indicating that sensing is done in both ventricles. The claim uses the term "detecting cardiac signals," indicating that several sensing electrodes would be used. While one could argue that the term "signals" as used means signals over time, instead of multiple signals at the same time, later in the claim the singular term "signal" is used to describe the control signal of the control circuit. If the term "signals" referred to one single source of a signal over time, the claim would use "signals" again later when referring to the control signal. The addition of the language "originating in the atrium and both ventricles" does not narrow the scope of the claim, as it was always directed to sensing in both ventricles. In fact, the addition of this language after "detecting cardiac signals" demonstrates even more clearly that there are signals, and not a signal, which require multiple sensing electrodes.
Thus, we agree with the district court that claims 15, 16, and 22-26 of the RE'119 patent are not invalid for recapturing the embodiment with only one sensing electrode by amendment.
Medtronic also argues that the embodiment with only one sensing electrode in the reissue claims was surrendered by argument. Guidant responds that the district court correctly held that this embodiment was not surrendered by argument.
As discussed above, if the claims of a reissue patent violate the recapture rule, the claims are invalid,
We see no error in the district court's ruling with respect to the arguments made to distinguish Nappholz. As the court noted, Mr. Nikolai's argument with respect to Nappholz was based on the proposition that Dr. Mower's invention was distinguishable over, and narrower than, Nappholz because it required two sensing electrodes. As indicated above, when a reissue claim, while broader in certain respects than the original patent claim, is materially narrowed in other respects, the recapture rule does not apply.
Moreover, further support for the district court's ruling lies in the fact that the statements regarding Nappholz made during prosecution of the '895 application were not unmistakable assertions in support of patentability over the embodiment with a single sensing electrode. Mr. Nikolai distinguished Nappholz from the conditional embodiment on the ground that Nappholz had only a single atrial electrode and a single ventricular electrode and thus was unable to sense and pace both ventricles.
As discussed above, Mr. Nikolai distinguished Cohen from his invention of the ground that Cohen had electrodes in the ventricles that paced but did not sense. This distinction is not relevant to the embodiment with only one sensing electrode, as Cohen cannot sense. Finally, as far as Rockland is concerned, Mr. Nikolai distinguished Rockland on the ground that it could not selectively analyze and, instead, described a device that paced over a predetermined time interval. This distinction is also irrelevant to the embodiment with only one sensing electrode, as that embodiment does not require a predetermined time period.
Thus, we agree with the district court that claims 15, 16, and 22-26 of the RE'119 patent are not invalid for recapturing the embodiment with only one sensing electrode because that embodiment was previously surrendered by argument.
In sum, we affirm the district court's determination that claims 15-26 of the RE'119 patent are not invalid. We do so because we agree with the district court that neither the unconditional embodiment nor the embodiment with only one sensing electrode, both of which were covered by those claims, was surrendered by amendment or argument during prosecution of the '895 application.
Each party shall bear its own costs.
DYK, Circuit Judge, concurring-in-part and dissenting-in-part.
I join the majority's opinion insofar as it holds that claims 15, 16 and 22-26 of the RE'119 patent did not impermissibly recapture the embodiment with only one sensing electrode. I dissent insofar as the majority holds that the reissue patent's claims 15-26, which claim the unconditional embodiment, did not violate the recapture rule, because I believe they impermissibly recapture the unconditional embodiment.
The recapture rule provides that an applicant may not regain, through reissue, subject matter that was deliberately surrendered during prosecution of the original patent in order to avoid a prior art rejection.
In considering whether a deliberate surrender of subject matter has occurred, we ask whether an objective observer viewing the prosecution history would conclude that such a deliberate surrender happened in order to avoid an obstacle to patentability.
It is clear, and the majority agrees, that claims 15 and 16, as originally drafted, covered the unconditional embodiment of the invention as well as its conditional embodiment. It is undisputed that, after the examiner's amendment to claims 15 and 16, those claims no longer covered the unconditional embodiment. The examiner's statements made at the time of the amendment of claims 15 and 16—characterizing the language changes as "minor wording changes"—on their face do not demonstrate a concern with patentability. However, it is quite clear that the amendments were not, in fact, minor wording changes, and the examiner stated that the amendments were necessary in order to put claims 15 and 16 "in condition for allowance." In light of the prosecution history, the amendments to claims 15-16, in my view, were plainly directed to patentability.
Claim 23 of the '895 application originally included both the conditional and unconditional embodiments, as did the original language of claims 15 and 16. On September 6, 1989, the examiner rejected claim 23 as obvious in light of the Rockland and Funke prior art. Mr. Nikolai's statements designed to overcome the rejection of claim 23 were clearly directed towards patentability. In his September 26, 1989, response to the examiner, Mr. Nikolai distinguished the prior art on the basis that Rockland could not "analyz[e] cardiac signals" and "selectively . . . stimulat[e] or pac[e]" one ventricle, in other words, that the prior art did not disclose the conditional embodiment. Claim 23 was then amended to add language limiting it to the conditional embodiment.
A few weeks after Mr. Nikolai's statements concerning claim 23 and the amendment to that claim, on December 5, 1989, the examiner similarly amended claims 15 and 16 to require "determining whether . . . signals . . . are simultaneously present," the very analysis function that Mr. Nikolai referred to in his claim 23 statement. The language of claims 15 and 16 was also amended, as the language of claim 23 had been amended, to make clear the conditional nature of the ventricle stimulation. Given this sequence of events, I think it is clear that the examiner's amendment to claims 15 and 16—which the majority agrees resulted in the elimination of the unconditional embodiment and the limitation of the those claims to the conditional embodiment—was made to avoid the same prior art that had caused claim 23's original rejection. In other words, an objective observer, viewing the prosecution history, would conclude that the unconditional embodiment was deliberately surrendered to avoid a prior art rejection of claim 23, and an analogous prior art problem in claims 15 and 16. Under these circumstances, the recapture of the unconditional embodiment in the reissue patent was improper.
(Emphasis in original).