Case 1:17-cv-00770-JDW Document 365 Filed 04/12/24 Page 1 of 32 PageID #: 33245
`
`IN THE UNITED STATES DISTRICT COURT
`FOR THE DISTRICT OF DELAWARE
`
`C.A. No. 17-770-JDW
`
`JURY TRIAL DEMANDED
`
`)))))))))
`
`WIRTGEN AMERICA, INC.,
`
`Plaintiff,
`
`v.
`
`CATERPILLAR INC.,
`
`Defendant.
`
`CATERPILLAR INC.’S OPENING BRIEF REGARDING ESTOPPEL DEFENSES
`
`Bindu A. Palapura (#5370)
`Andrew L. Brown (#6766)
`Hercules Plaza, 6th Floor
`POTTER ANDERSON & CORROON LLP
`1313 N. Market Street
`Wilmington, DE 19801
`Tel: (302) 984-6000
`bpalapura@potteranderson.com
`abrown@potteranderson.com
`
`Attorneys for Defendant Caterpillar Inc.
`
`OF COUNSEL:
`
`James C. Yoon
`Ryan R. Smith
`Christopher D. Mays
`WILSON SONSINI GOODRICH & ROSATI, P.C.
`650 Page Mill Road
`Palo Alto, CA 94304
`Tel: (650) 493-9300
`
`Lucy Yen
`Cassie Leigh Black
`WILSON SONSINI GOODRICH & ROSATI, P.C.
`1301 Avenue of the Americas, 40th Floor
`New York, NY 10019
`Tel: (212) 999-5800
`
`Matthew A. Macdonald
`Neil N. Desai
`Naoya Son
`Alex J. Turner
`WILSON SONSINI GOODRICH & ROSATI, P.C.
`953 E. 3rd St., #100
`Los Angeles, California 90013
`Tel: (323) 210-2900
`
`Dated: April 12, 2024
`11445268/11898.00005
`
`

`

`Case 1:17-cv-00770-JDW Document 365 Filed 04/12/24 Page 2 of 32 PageID #: 33246
`
`TABLE OF CONTENTS
`
`I.
`
`II.
`
`Page
`INTRODUCTION ...............................................................................................................1
`
`Wirtgen should be judicially estopped from taking Inconsistent Positions on The
`’309 Patent ...........................................................................................................................3
`
`A.
`B.
`C.
`
`D.
`
`E.
`
`Legal Standards for Judicial Estoppel ......................................................................3
`The ’309 Patent ........................................................................................................4
`Wirtgen Took Inconsistent Positions .......................................................................5
`
`1.
`
`2.
`
`Before the Patent Office, Wirtgen Successfully Argued that the
`Four-Sided Stability Pattern Is Not Inherent ................................................5
`At Trial, Wirtgen Argued that the Four-Sided Stability Is Inherent ............6
`
`The Patent Office Adopted Wirtgen’s Prior Position, and Bad Faith Can
`Be Inferred ...............................................................................................................7
`Judicial Estoppel Is Tailored to Address the Harm .................................................8
`
`III.
`
`THE ’530 PATENT IS UNENFORCEABLE DUE TO PROSECUTION
`LACHES ..............................................................................................................................9
`
`A.
`B.
`
`C.
`
`D.
`
`Legal Standards for Prosecution Laches ..................................................................9
`Wirtgen Unreasonably Delayed Seeking Claims Covering Legs that Are
`Not Each Individually Adjustable ..........................................................................10
`
`1.
`2.
`3.
`
`Caterpillar’s Legacy Machines ..................................................................11
`The ’530 Patent Family ..............................................................................11
`Caterpillar’s PM600 Series Cold Planers ..................................................12
`
`Wirtgen’s Delay in Prosecuting Broadened Claims for the ’530 Patent
`Was Unreasonable .................................................................................................13
`Caterpillar Suffered Prejudice Attributable to Wirtgen’s Delay ............................15
`
`IV.
`
`The ’268 Patent is unenforceable against Caterpillar because of Equitable AND
`ABSOLUTE Intervening Rights ........................................................................................16
`
`A.
`B.
`C.
`
`Legal Standards for Equitable Intervening Rights .................................................16
`The Predecessor ’659 Patent and the Reissued ’268 Patent ..................................17
`Caterpillar Launched New Products in Good Faith and Has Intervening
`Rights .....................................................................................................................18
`
`V.
`
`COLLATERAL ESTOPPEL BARS WIRTGEN FROM ASSERTING CLAIM 5
`OF THE ’788 PATENT .....................................................................................................19
`
`A.
`B.
`
`Legal Standards for Collateral Estoppel ................................................................19
`The ’395 and ’788 Patents .....................................................................................20
`
`-i-
`
`

`

`Case 1:17-cv-00770-JDW Document 365 Filed 04/12/24 Page 3 of 32 PageID #: 33247
`
`C.
`
`Claim 5 of the ’788 Patent Presents the Identical Issue of Invalidity as
`Invalidated Claim 1 of the ’395 Patent ..................................................................21
`
`1.
`2.
`
`Claims 1 of the ’788 and ’395 Patents Are Legally Identical ....................21
`Claim 5 of the ’788 Patent Adds Only Obvious, Legally
`Immaterial Limitations to Claim 1 of the ’788 Patent ...............................22
`
`VI.
`
`CONCLUSION ..................................................................................................................24
`
`-ii-
`
`

`

`Case 1:17-cv-00770-JDW Document 365 Filed 04/12/24 Page 4 of 32 PageID #: 33248
`
`TABLE OF AUTHORITIES
`
`CASES
`
`Page(s)
`
`Akamai Techs. v. Limelight Networks,
`805 F.3d 1368 (Fed. Cir. 2015)............................................................................................4
`Aspex Eyewear, Inc. v. Marchon Eyewear, Inc.,
`672 F.3d 1335 (Fed. Cir. 2012)..........................................................................................20
`BIC Leisure Prod. v. Windsurfing Int’l,
`1 F.3d 1214 (Fed. Cir. 1993)..............................................................................................19
`Biogen Int’l GmbH v. Amneal Pharms. LLC,
`487 F. Supp. 3d 254 (D. Del. 2020) ...................................................................................20
`Biogen Int’l GmbH v. Mylan Pharms. Inc.,
`No. 1:17-cv-116, 2020 WL 3317105 (N.D. W. Va. June 18, 2020) ................................3, 4
`Cancer Research Tech. Ltd. v. Barr Labs., Inc.,
`625 F.3d 724 (Fed Cir. 2010).............................................................................................10
`Caterpillar Inc. v. Wirtgen Am., Inc.,
`Case No. 19-2294, D.I. 79 (Fed. Cir. Feb. 3, 2021) .............................................................6
`Eberle v. Harris,
`No. 03-cv-5809 (FLW), 2010 WL 6281563 (D.N.J. June 30, 2010).................................18
`Eli Lilly & Co. v. Hospira, Inc.,
`933 F.3d 1320 (Fed. Cir. 2019)..........................................................................................17
`Festo Corp. v. Shoketsu Kinzoku Kogyo Kabushiki Co.,
`535 U.S. 722 (2002) ...........................................................................................................13
`Google LLC v. Hammond Dev. Int’l, Inc.,
`54 F.4th 1377 (Fed. Cir. 2022) ..........................................................................................20
`Hyatt v. Hirshfeld,
`998 F.3d 1347 (Fed. Cir. 2021)......................................................................................9, 15
`IMEG Corp. v. Patel,
`C.A. No. 20-111-CFC, 2021 WL 184407 (D. Del. Jan. 19, 2021) ......................................9
`John Bean Techs. Corp. v. Morris & Assocs., Inc.,
`No. 4:14-CV-00368-BRW, 2019 WL 7176779 (E.D. Ark. Sept. 23, 2019),
`aff’d, 988 F.3d 1334 (Fed. Cir. 2021) ....................................................................16, 17, 18
`Krystal Cadillac-Oldsmobile GMC Truck, Inc. v. GMC.,
`337 F.3d 314 (3d Cir. 2003).................................................................................................4
`
`-iii-
`
`

`

`Case 1:17-cv-00770-JDW Document 365 Filed 04/12/24 Page 5 of 32 PageID #: 33249
`
`KSR Int’l Co. v. Teleflex Inc.,
`550 U.S. 398 (2007) ...........................................................................................................22
`Laitram Corp. v. NEC Corp.,
`163 F.3d 1342 (Fed. Cir. 1998)..........................................................................................12
`Miller v. Brass Co.,
`104 U.S. 350 (1881) .............................................................................................................9
`Montrose Med. Grp. v. Bulger,
`243 F.3d 773 (3d Cir. 2001).................................................................................................8
`New Hampshire v. Maine,
`532 U.S. 742 (2001) .........................................................................................................3, 4
`Ohio Willow Wood Co. v. Alps South., LLC
`735 F.3d 1333 (Fed. Cir. 2013)....................................................................................20, 24
`Par Pharm., Inc. v. TWi Pharms., Inc.,
`773 F.3d 1186 (Fed. Cir. 2014)....................................................................................5, 6, 7
`Personalized Media Commc’ns, LLC v. Apple Inc.,
`57 F.4th 1346 (Fed. Cir. 2023) ............................................................................................9
`Predicate Logic, Inc. v. Distributive Software, Inc.,
`544 F.3d 1298 (Fed. Cir. 2008)..........................................................................................19
`Reiffin v. Microsoft Corp.,
`270 F. Supp. 2d 1132 (N.D. Cal. 2003) .............................................................9, 10, 14, 15
`Shire Labs, Inc. v. Corepharma, LLC,
`No. CIV. A. 06-2266 SRC, 2008 WL 4822186 (D.N.J. Nov. 3, 2008) ...........................8, 9
`Sonos, Inc. v. Google LLC,
`No. C 20-06754 WHA, 2023 WL 6542320 (N.D. Cal. Oct. 6, 2023) .........................14, 15
`Trs. in Bankr. of N. Am. Rubber Thread Co. v. United States,
`593 F.3d 1346 (Fed. Cir. 2010)............................................................................................3
`Trs. of Columbia Univ. in N.Y. v. NortonLifeLock, Inc.,
`No. 3:13-CV-808, 2019 WL 7040931 (E.D. Va. Dec. 20, 2019) ........................................8
`U.S. Ethernet Innovations, LLC v. Tex. Instruments Inc.,
`No. 6:11-cv-491, 2014 WL 2740383 (E.D. Tex. June 15, 2014) ........................................8
`Wang Labs., Inc. v. Applied Comp. Scis., Inc.,
`958 F.2d 355 (Fed. Cir. 1992)..............................................................................................4
`Webster Elec. Co. v. Splitdorf Elec. Co.,
`264 U.S. 463 (1924) .............................................................................................................9
`Woodbridge v. United States,
`263 U.S. 50 (1923) ...............................................................................................................9
`
`-iv-
`
`

`

`Case 1:17-cv-00770-JDW Document 365 Filed 04/12/24 Page 6 of 32 PageID #: 33250
`
`STATUTES
`35 U.S.C. § 252 ..............................................................................................................................16
`
`-v-
`
`

`

`Case 1:17-cv-00770-JDW Document 365 Filed 04/12/24 Page 7 of 32 PageID #: 33251
`
`TABLE OF ABBREVIATIONS
`
`Abbreviation
`
`’268 patent
`’309 patent
`’395 patent
`’530 patent
`’592 patent
`’659 patent
`’788 patent
`’871 patent
`EP ’004 patent
`CAFC
`Engelmann Decl.
`Ex.
`
`FH
`Klopp Decl.
`POR
`POS
`POSA
`PTAB
`Smith Decl.
`Wirtgen
`
`Word or Phrase
`U.S. Patent No. RE48,268
`U.S. Patent No. 7,828,309
`U.S. Patent No. 8,308,395
`U.S. Patent No. 9,656,530
`U.S. Patent No. 8,113,592
`U.S. Patent No. 8,408,659
`U.S. Patent No. 7,946,788
`U.S. Patent No. 9,010,871
`European Patent No. 1,875,004
`Court of Appeals for the Federal Circuit
`Declaration of Eric Engelmann
`Exhibits attached to the Declaration of Naoya
`Son
`File history
`Declaration of Richard Klopp, Ph.D.
`IPR Patent Owner Response
`IPR Patent Owner Statement
`Person of ordinary skill in the art
`Patent Trial and Appeal Board
`Declaration of Andrew Smith, Ph.D.
`Wirtgen Group (including Wirtgen America
`and Wirtgen GmbH working in concert in
`connection with enforcement activities
`directed towards the asserted patents)
`
`*All emphases in the brief are added unless otherwise noted.
`
`-vi-
`
`

`

`Case 1:17-cv-00770-JDW Document 365 Filed 04/12/24 Page 8 of 32 PageID #: 33252
`
`I.
`
`INTRODUCTION
`
`The patent system is intended to promote innovation, not reward legal gamesmanship. But
`
`in its relentless litigation campaign against Caterpillar, Wirtgen has used the patent system to
`
`compete unfairly against its biggest competitor in violation of equitable principles designed to
`
`prevent precisely the type of misconduct perpetrated by Wirtgen. Wirtgen has taken inconsistent
`
`positions before the Patent Office and this Court; it has amended pending patent claims for the
`
`sole purpose of targeting Caterpillar machines already on the market; and it has attempted to
`
`enforce reissued patents years after predecessor claims were held invalid. The patent laws do not
`
`countenance such tactics and bar enforcement of the ’309, ’530, ’268, and ’788 patents against
`
`Caterpillar.
`
`’309 Patent. Judicial estoppel bars Wirtgen from asserting the ’309 patent against
`
`Caterpillar because Wirtgen’s position in this lawsuit is in irreconcilable conflict with positions it
`
`took (and prevailed on) in IPR proceedings. Before the Patent Office, to support patentability,
`
`Wirtgen argued that the “four-sided stability pattern” described in the ’309 patent was not
`
`inherently present in a four-way floating suspension (a suspension that had been described in the
`
`prior art). Then, at trial, to support infringement, Wirtgen’s expert, Dr. John Lumkes, argued
`
`exactly the opposite, namely that the accused machines must have a four-sided stability pattern
`
`because they have a four-way floating suspension. Having argued one position to defend the
`
`validity of its patent (and prevailing), Wirtgen cannot now argue the opposite to prove
`
`infringement.
`
`’530 Patent. Prosecution laches bars Wirtgen from enforcing the ’530 patent against
`
`Caterpillar because Wirtgen unjustifiably delayed asserting its claims, waiting until after
`
`Caterpillar had, at great expense, released the accused products in the market. The ’530 patent is
`
`a member of a patent family dating back to 2008. In the decade before the ’530 patent issued,
`
`

`

`Case 1:17-cv-00770-JDW Document 365 Filed 04/12/24 Page 9 of 32 PageID #: 33253
`
`Wirtgen limited the relevant claims in the family to road building machines with legs that were
`
`each “individually adjustable.” It was not until 2017—after Caterpillar designed, developed, and
`
`launched the PM600 series, and after Wirtgen had purchased and scrutinized multiple PM600
`
`series machines—that Wirtgen removed the “individually adjustable” claim limitation, thus
`
`exposing Caterpillar for the first time to infringement allegations for its machine legs that had
`
`moved in unison dating back to the 1990s. The delay has prejudiced Caterpillar, and Wirtgen is
`
`barred from enforcing the ’530 patent against Caterpillar.
`
`’268 Patent.1 The intervening rights doctrine bars Wirtgen’s delayed efforts to enforce the
`
`’268 patent against Caterpillar. Caterpillar successfully invalidated the predecessor foreign
`
`counterpart to the ’268 patent based on prior art Caterpillar machines. Having done so, and with
`
`no notice of infringement or any other communication from Wirtgen about the ’268 patent,
`
`Caterpillar had no reason to believe that its substantial development and investment in new cold
`
`planer machines could potentially infringe any “reissued” patents or claims. Because Wirtgen’s
`
`reissued ’268 patent claims significantly postdate Caterpillar’s substantial investment in the
`
`development of PM600 and PM800 machines (which had been on the market years before the ’268
`
`patent issued in 2020), the doctrine of intervening rights bars Wirtgen’s current claims against
`
`those products.
`
`’788 Patent. Collateral estoppel bars Wirtgen from enforcing claim 5 of the ’788 patent
`
`because the claim is substantially similar to a patent claim previously invalidated by the Patent
`
`Office. In response to challenges by Caterpillar, the Patent Office invalidated claim 1 of the ’395
`
`patent, which is in the same family as the ’788 patent, and whose claim 1 is materially identical to
`
`1 The jury found the ’268 patent invalid and not infringed. As such, the Court need only rule on
`its unenforceability if the Court grants any JMOL motion filed by Wirtgen that is directed towards
`the ’268 patent.
`
`-2-
`
`

`

`Case 1:17-cv-00770-JDW Document 365 Filed 04/12/24 Page 10 of 32 PageID #: 33254
`
`claim 1 of the ‘788 patent. While claim 5 of the ’788 patent has additional limitations beyond
`
`those of claim 1, Wirtgen’s infringement theory at trial read-out those limitations and removed any
`
`possible difference in the patentability questions. Because claim 5 of the ’788 patent raises
`
`indistinguishable patentability issues from claim 1 of the ’395 patent, Wirtgen is collaterally
`
`estopped from enforcing claim 5 of the ’788 patent against Caterpillar.
`
`Wirtgen’s misuse of the patent system is undeniable and pervasive. Focused on
`
`handicapping its biggest competitor at all costs, Wirtgen has demonstrated that it will say and do
`
`whatever it takes in the moment to secure a patent and then enforce it against Caterpillar. That is
`
`not the purpose of the patent system, and the doctrines of judicial estoppel, prosecution laches,
`
`intervening rights, and collateral estoppel expressly prohibit such gamesmanship. As discussed
`
`below, given the inconsistent prior positions and unreasonable delay, the Court should bar Wirtgen
`
`from enforcing these patents against Caterpillar.
`
`II. WIRTGEN SHOULD BE JUDICIALLY ESTOPPED FROM TAKING
`INCONSISTENT POSITIONS ON THE ’309 PATENT
`
`A.
`
`Legal Standards for Judicial Estoppel
`
`“[W]here a party assumes a certain position in a legal proceeding, and succeeds in
`
`maintaining that position, he may not thereafter, simply because his interests have changed,
`
`assume a contrary position, especially if it be to the prejudice of the party who has acquiesced in
`
`the position formerly taken by him.” New Hampshire v. Maine, 532 U.S. 742, 749 (2001). This
`
`rule applies equally to positions taken before an agency (including the patent office). See Trs. in
`
`Bankr. of N. Am. Rubber Thread Co. v. United States, 593 F.3d 1346, 1354 (Fed. Cir. 2010);
`
`Biogen Int’l GmbH v. Mylan Pharms. Inc., No. 1:17-cv-116, 2020 WL 3317105, at *8 n.15 (N.D.
`
`-3-
`
`

`

`Case 1:17-cv-00770-JDW Document 365 Filed 04/12/24 Page 11 of 32 PageID #: 33255
`
`W. Va. June 18, 2020) (applying judicial estoppel to IPR proceedings). The Third Circuit2 looks
`
`at various factors in evaluating judicial estoppel, including whether the party’s position is clearly
`
`inconsistent with an earlier position, whether the party changing position would obtain an unfair
`
`advantage from the change in position, and whether judicial estoppel would be tailored to address
`
`the harm. See Krystal Cadillac-Oldsmobile GMC Truck, Inc. v. GMC., 337 F.3d 314, 319 (3d Cir.
`
`2003) (finding judicial estoppel based on omission of potential claim against GM in bankruptcy
`
`disclosure form and subsequent pursuit of claim against GM in litigation).
`
`B.
`
`The ’309 Patent
`
`When a typical roadbuilding machine travels over an obstacle with only one wheel, that
`
`wheel (and its supporting cylinder) may be raised by the obstacle, causing instability. See
`
`Engelmann Decl. ¶¶ 3, 8. The ’309 patent purports to provide an improved suspension system
`
`whereby all four supporting cylinders are “positive[ly] couple[d]” so that, when going over an
`
`obstacle, they all adjust in response: “the left front wheel and the right rear wheel are adjusted in
`
`height in the opposite direction to the right front wheel and the left rear wheel, the left front wheel
`
`and the right rear wheel being adjusted in height in the same direction.” Ex. 38 (’309 patent) at
`
`6:54-59. The ’309 patent goes on to explain that this positive coupling results in an enhanced,
`
`four-sided stability pattern, as depicted in Figure 7:
`
`2 In a patent case, the Federal Circuit reviews “questions of judicial estoppel under the law of the
`regional circuit where the district court sits.” See Akamai Techs. v. Limelight Networks, 805 F.3d
`1368 (Fed. Cir. 2015) (“This court reviews challenges to jury instructions, grants or denials of
`motions for JMOL, and questions of judicial estoppel under the law of the regional circuit where
`the district court sits.”); see also Wang Labs., Inc. v. Applied Comp. Scis., Inc., 958 F.2d 355, 358
`(Fed. Cir. 1992) (applying First Circuit law to issue of judicial estoppel). We assume that Third
`Circuit law would follow the Supreme Court’s guidance in New Hampshire concerning the
`applicability of judicial estoppel. New Hampshire, 532 U.S. at 749.
`
`-4-
`
`

`

`Case 1:17-cv-00770-JDW Document 365 Filed 04/12/24 Page 12 of 32 PageID #: 33256
`
`C.
`
`Wirtgen Took Inconsistent Positions
`
`1.
`
`Before the Patent Office, Wirtgen Successfully Argued that the Four-
`Sided Stability Pattern Is Not Inherent
`
`Caterpillar brought an IPR challenge to the ’309 patent based on the combination of two
`
`prior art sources: Swisher (which disclosed a road milling machine) and Neumeier (which
`
`disclosed a front loader machine with the four-way positively coupled actuating members, or
`
`cylinders, as described in claim 26 of the ’309 patent). Caterpillar argued that a POSA would have
`
`been motivated to modify a road milling machine to incorporate Neumeier’s hydraulic cylinder
`
`system.
`
`To address the four-sided-stability pattern depicted in the ’309 patent, Caterpillar argued
`
`that this was an inherent feature of the ’309 patent’s four-way positive coupling described above.
`
`See id. at 6:54-59. Under the law, inherency means that “the limitation at issue necessarily must
`
`be present, or the natural result of the combination of elements explicitly disclosed by the prior
`
`art.” Par Pharm., Inc. v. TWi Pharms., Inc., 773 F.3d 1186, 1195-96 (Fed. Cir. 2014).
`
`In response, Wirtgen argued that the four-sided stability pattern was not inherent:
`
`[T]he ’309 patent does not acknowledge the claim feature is inherent. Caterpillar
`selectively relies on the ’309 patent’s teachings, ignoring those teachings that show
`the missing element is not necessarily present. The ’309 patent states that “[i]f all
`of the actuating members are designed identically … the height adjustment takes
`
`-5-
`
`

`

`Case 1:17-cv-00770-JDW Document 365 Filed 04/12/24 Page 13 of 32 PageID #: 33257
`
`place essentially by equal amounts on all the wheels.” [’309 patent] 2:55-58. But
`the ’309 patent adds that this is only theoretical “on the precondition that, for
`example, the machine frame is indefinitely rigid, the contact area is totally
`inflexible and the oil is fully incompressible.” [Id.] at 2:58-63. “In practice,
`however, minor deviations cannot be avoided.” [Id.] at 2:63-64. Deviations will
`influence the tilting behavior, and thus the stability pattern, of the road-building
`machine. [Id.] 2:64-67. Caterpillar ignored these factors in making its inherency
`argument.
`
`Ex. 1 (’309 POS) at 47-48.3
`
`The Patent Office accepted Wirtgen’s non-inherency arguments. Although the Patent
`
`Office found claim 26 (describing the four-way positive coupling) of the ‘309 patent obvious, see
`
`Ex. 12 (IPR2017-02185 Final Written Decision) at 42, it sided with Wirtgen on claim 29,
`
`endorsing Wirtgen’s non-inherency
`
`theory: “While
`
`it
`
`is possible
`
`that
`
`the proposed
`
`Swisher/Neumeier combination may have a four-sided stability pattern as recited in [claim 29], a
`
`mere possibility is not enough . . . a preponderance of the evidence does not establish that the
`
`Swisher/Neumeier combination inherently has a four-sided stability pattern . . . .” Id. at 54-55.
`
`The Federal Circuit affirmed this finding. See Caterpillar Inc. v. Wirtgen Am., Inc., Case No. 19-
`
`2294, D.I. 79 (Fed. Cir. Feb. 3, 2021) (Judgment).
`
`2.
`
`At Trial, Wirtgen Argued that the Four-Sided Stability Is Inherent
`
`At the trial in this case, Wirtgen adopted a wholly different position. Without any
`
`supporting testimony from inventors or engineers, Wirtgen presented its entire infringement case
`
`for the “four-sided stability” limitation of the ’309 patent through a single conclusory opinion of
`
`its technical expert, Dr. John Lumkes:
`
`Q. Professor, when the ride control is active, could you explain why this is in fact
`four-sided stability pattern?
`
`A. So when the ride control is active and those lines are hooked together, and one
`
`3 Along the same lines, Wirtgen pointed to “Caterpillar’s European patent EP 0940274 B1
`(‘Bitelli’) [which] show[ed] that the location of a stability pattern’s apex between two coupled
`cylinders is not inherent.” Id.
`
`-6-
`
`

`

`Case 1:17-cv-00770-JDW Document 365 Filed 04/12/24 Page 14 of 32 PageID #: 33258
`
`cylinder has to move up and one cylinder has to move down, it creates a four-sided
`stability pattern that is shown here. […]
`
`Q. […] How do you determine whether the four-sided stability pattern having a
`widest transverse dimension transverse to the forward direction of the chassis fell
`within the footprint of Wirtgen rotor?
`
`A. Yes. So I was provided a CAD, or I think you have heard the term in here,
`computer-aided design file, a complete parts drawing of the machine, that parts file
`model, computer model machine and all the dimensions of the machine. From that,
`I was able to determine the stability pattern, it has to occur at the midpoints of
`the legs, since all the cylinders are equal value, one goes up and one goes down,
`it's going to pivot and that is going to cause that pivot point to be in the middle of
`those legs. Whether it goes up and down, that’s the pivoting access of the drawing,
`the diagram of the center of the point between the front legs, the front to back legs
`and the rear legs, you get that triangular shape, from that CAD file it has all these
`documents in there, you see those midpoint lines, draw the stability pattern or the
`four-side shape and actually look on the CAD file and say yes, it does or doesn't
`fall within the working rotor.
`
`D.I. 353 (Trial Tr.) at 595:14-596:24. Dr. Lumkes concluded that “since all the cylinders [i.e., the
`
`actuating members] are equal value,” the accused machines must have a four-sided stability
`
`pattern. He did no testing to verify that Caterpillar’s machines in fact had that stability pattern: he
`
`did not verify that the “machine frame is indefinitely rigid,” that “the contact area is totally
`
`inflexible,” or that “the oil is fully incompressible.” Cf. Ex. 1 (’309 POS) at 47-48. Nor did he do
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`anything to rule out the possibility of “[d]eviations . . . influenc[ing] the tilting behavior and thus
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`the stability pattern” of the PM600 series. Id. Instead, he stated that because the cylinders were
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`allegedly “of equal value,” the four-way stability pattern “necessarily must be present.” See Par
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`Pharma., 773 F.3d at 1195-96. That is precisely the opposite of what Wirtgen advocated before
`
`the Patent Office.
`
`D.
`
`The Patent Office Adopted Wirtgen’s Prior Position, and Bad Faith Can Be
`Inferred
`
`Given Wirtgen’s gamesmanship, judicial estoppel is proper here. Having successfully
`
`advanced one position before the Patent Office, Wirtgen should not now be permitted to change
`
`-7-
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`

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`Case 1:17-cv-00770-JDW Document 365 Filed 04/12/24 Page 15 of 32 PageID #: 33259
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`that position in order to obtain an unfair advantage. This is exactly the kind of bad-faith change
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`of position that the doctrine is designed to prevent. See generally Shire Labs, Inc. v. Corepharma,
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`LLC, No. CIV. A. 06-2266 SRC, 2008 WL 4822186, at *8 (D.N.J. Nov. 3, 2008) (“bad faith”
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`shown because party’s change of position would “allow it to gain an advantage unfairly”);
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`Montrose Med. Grp. v. Bulger, 243 F.3d 773, 782 (3d Cir. 2001) (“If the second tribunal adopted
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`the party’s inconsistent position, then at least one court has probably been misled.”). Wirtgen’s
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`inconsistent position is particularly egregious where Caterpillar was estopped by the same IPR
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`proceeding from challenging the validity of the ’309 patent at trial (D.I. 272 at 22-26) – this is in
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`fact what made it possible for Wirtgen to make the new arguments that it otherwise would not have
`
`been able to make. Because Caterpillar was estopped from arguing that Wirtgen’s new position
`
`would invalidate the ’309 patent, Wirtgen was able to adopt an irreconcilably inconsistent position
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`for infringement contrary to its prior validity position.
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`Numerous courts have held that a party who successfully defends the validity of a patent
`
`may not later change its position to win on infringement. See, e.g., Trs. of Columbia Univ. in N.Y.
`
`v. NortonLifeLock, Inc., No. 3:13-CV-808, 2019 WL 7040931, at *5-6 (E.D. Va. Dec. 20, 2019)
`
`(where party prevailed on interpretation of term before PTAB, party was precluded from arguing
`
`for different interpretation of term at claim construction); U.S. Ethernet Innovations, LLC v. Tex.
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`Instruments Inc., No. 6:11-cv-491, 2014 WL 2740383, at *2-3 (E.D. Tex. June 15, 2014) (barring
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`party who had prevailed at trial on invalidity from taking contradictory infringement positions).
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`Wirtgen cannot have it both ways—either the four-sided stability pattern is inherent (and the patent
`
`is invalid) or it is not inherent (and Caterpillar does not infringe).
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`E.
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`Judicial Estoppel Is Tailored to Address the Harm
`
`Finally, with respect to the third factor, applying judicial estoppel is necessary to avoid
`
`injustice to Caterpillar, and to decline to apply judicial estoppel would result in a miscarriage of
`
`-8-
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`

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`Case 1:17-cv-00770-JDW Document 365 Filed 04/12/24 Page 16 of 32 PageID #: 33260
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`justice. There is nothing unfair about holding Wirtgen to its prior positions advocated before the
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`Patent Office. See, e.g., Shire Labs., 2008 WL 4822186, at *9; IMEG Corp. v. Patel, C.A. No.
`
`20-111-CFC, 2021 WL 184407, at *8 (D. Del. Jan. 19, 2021) (“No other sanction can remedy the
`
`damage caused by Patel’s assertion of contradictory positions.”). Wirtgen should thus be judicially
`
`estopped from trying to benefit from taking entirely irreconcilable positions, and Caterpillar will
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`further address the impact of estoppel on non-infringement in its upcoming JMOL motion.
`
`III.
`
`THE ’530 PATENT IS UNENFORCEABLE DUE TO PROSECUTION LACHES
`
`A.
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`Legal Standards for Prosecution Laches
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`“The prosecution laches defense originates from two Supreme Court cases in the early
`
`1900s.” Hyatt v. Hirshfeld, 998 F.3d 1347, 1360 (Fed. Cir. 2021); see Woodbridge v. United
`
`States, 263 U.S. 50 (1923) (finding prosecution laches after nine-year delay); Webster Elec. Co. v.
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`Splitdorf Elec. Co., 264 U.S. 463 (1924) (finding prosecution laches after eight-year delay). A
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`patent is not enforceable “when it has issued only after an unreasonable and unexplained delay in
`
`prosecution” based on the totality of the circumstances. Hyatt, 998 F.3d at 1360. As the Court
`
`explained in Miller v. Brass Co., 104 U.S. 350, 355 (1881), “[i]t will not do for the patentee to
`
`wait until other inventors have produced new forms of improvement, and then, with the new light
`
`thus acquired, under pretence [sic] of inadvertence and mistake, apply for such an enlargement of
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`his claim as to make it embrace these new forms.”
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`Prosecution laches has two elements: “(a) that the patentee’s delay in prosecution was
`
`unreasonable and inexcusable under the totality of circumstances, and (b) that the accused infringer
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`suffered prejudice attributable to the delay.” Hyatt, 998 F.3d at 1362; Personalized Media
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`Commc’ns, LLC v. Apple Inc., 57 F.4th 1346, 1354 (Fed. Cir. 2023). As to the first, where there
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`is evidence of delay, not just any excuse will do; the patentee must offer a reasonable explanation
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`for the delay. See Reiffin v. Microsoft Corp., 270 F. Supp. 2d 1132, 1153 (N.D. Cal. 2003) (even
`
`-9-
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`

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`Case 1:17-cv-00770-JDW Document 365 Filed 04/12/24 Page 17 of 32 PageID #: 33261
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`“the most unreasonable conduct in the prosecution of a patent can be explained in some fashion”).
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`As a matter of law, the patentee’s financial self-interests, such as the strategic benefit that a
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`patentee might receive from delaying prosecuti