  United States Court of Appeals
      for the Federal Circuit
                ______________________


     UNITED ACCESS TECHNOLOGIES, LLC,
              Plaintiff-Appellant

                           v.

   CENTURYTEL BROADBAND SERVICES LLC,
          QWEST CORPORATION,
            Defendants-Appellees
           ______________________

                      2014-1347
                ______________________

    Appeal from the United States District Court for the
District of Delaware in No. 1:11-cv-00339-LPS, Chief
Judge Leonard P. Stark.
                ______________________

              Decided: February 12, 2015
               ______________________

   ANTHONY MATTHEW GARZA, Charhon Callahan Robson
& Garza, PLLC, Dallas, TX, argued for plaintiff-
appellant. Also represented by STEVEN CHASE CALLAHAN,
BRETT CHARHON.

    MATTHEW CHRISTOPHER GAUDET, Duane Morris LLP,
Atlanta, GA, argued for defendants-appellees.   Also
represented by L. NORWOOD JAMESON; KRISTINA CAGGIANO
KELLY, Washington, DC.
                 ______________________
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Before NEWMAN, BRYSON, and O’MALLEY, Circuit Judges.
BRYSON, Circuit Judge.
    This appeal by a patent owner requires us to address
the collateral estoppel effects of a general jury verdict in a
prior action involving the same patents. The district
court held that the jury’s verdict against the patentee in
the prior action was entitled to collateral estoppel effect in
this proceeding. We reverse.
                              I
     Plaintiff-appellant United Access Technologies, LLC
(“United”), is the owner of U.S. Patent Nos. 5,844,596;
6,243,446; and 6,542,585. The asserted claims of the
three patents recite systems for using a landline tele-
phone connection for both voice communication and data
transmission. The inventions are directed to the use of
exchanges that combine the voice and data components of
the signal for transmission over the telephone line, and
filters that separate those components so that they can be
received as separate voice and data signals by a user.
    In 2002, United’s predecessor in interest, Inline Con-
nection Corporation, brought suit against EarthLink, Inc.,
charging EarthLink with direct infringement of various
claims of the three patents. Inline’s theory of the case
was that EarthLink offered its customers an Internet
connection service based on a broadband digital commu-
nications technology known as Asymmetrical Digital
Subscriber Line (“ADSL”), and that Earthlink’s ADSL
service infringed the asserted patents.         EarthLink’s
defense was that it did not infringe, for two reasons: first,
the ADSL technology did not infringe the patents; and
second, Earthlink’s accused ADSL system did not include
a “telephone device” as required by all asserted claims.
    The jury in the EarthLink case returned a general
verdict of non-infringement with respect to all of the
UNITED ACCESS TECHNOLOGIES   v. CENTURYTEL BROADBAND      3
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asserted claims. Nothing in the verdict form or the other
aspects of the record indicated what ground for decision
the jury had adopted in reaching its verdict.
    Inline moved for judgment as a matter of law
(“JMOL”). The trial court denied the motion, holding that
the jury’s verdict of non-infringement was supported by
the evidence. In particular, the court ruled that the jury’s
verdict could be upheld on either of two theories: (1) the
jury could have concluded that Inline failed to carry its
burden to show that the ADSL technology infringed the
asserted claims, or (2) the jury could have found that
EarthLink did not infringe because none of its systems
included a telephone, which was a required element of
each of the asserted claims.
    In its response to Inline’s JMOL motion, EarthLink
argued that the testimony of Inline’s expert, including his
conclusion that standard ADSL services infringe the
claims of the patents in suit, was heavily impeached
during cross-examination. The trial court agreed with
EarthLink that a reasonable jury “could have determined
that [the expert] was impeached during his testimony
and, therefore, lacked credibility,” and that, “[b]ased on
such determination, the jury could reasonably have
returned its non-infringement verdict.” In its second
argument in response to Inline’s JMOL motion, Earth-
Link contended that the evidence showed that telephones
and telephone service were separate from the Internet
access service offered by EarthLink, and that EarthLink’s
accused service had no connection to the telephone service
at all. Again, the trial court agreed with EarthLink and
ruled that “since at least one ‘telephone device’ is an
element of each of the asserted claims, the absence of
evidence that EarthLink’s system includes that element is
substantial evidence upon which the jury could have
returned its non-infringement verdict.”
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   On appeal from the trial court’s judgment in the
EarthLink case, this court affirmed without opinion.
United Access Techs., LLC v. EarthLink, Inc., 432 F.
App’x 976 (Fed. Cir. 2011).
     In 2011, United, as Inline’s successor, filed this action
against defendants-appellees CenturyTel Broadband
Services LLC, and Qwest Corporation. United charged
the defendants with infringing the same claims of the
three patents that had been asserted against EarthLink.
CenturyTel and Qwest sought dismissal of United’s
claims based on collateral estoppel. Their theory was that
the jury’s verdict in the EarthLink case established as a
matter of law that the industry standard ADSL technolo-
gy did not infringe United’s patents. Because United
failed to show that the ADSL services sold by CenturyTel
and Qwest differed in any material respect from the
ADSL services that had been sold by EarthLink, they
contended that the prior proceedings collaterally estopped
United from proving infringement in the present action.
    The district court agreed with the defendants and
dismissed the action on collateral estoppel grounds. The
court began its analysis by noting that United had not
been able to articulate how the defendants’ systems were
different from the systems that were the subjects of the
trial in the EarthLink case. The court explained that
United had identified only a single potential distinguish-
ing factor between EarthLink’s services and those offered
by the defendants in this case: that EarthLink’s services
did not include telephone devices, but provided an access
service that was distinct from any service involving the
use of a telephone, while the defendants’ services included
telephone devices.
    The district court rejected that proposed distinction,
stating that it “does nothing to account for the fact that
the issue whether industry standard ADSL infringes the
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patents-in-suit was litigated, and lost, by the Plaintiff in
the EarthLink action.” The court added:
   At best, Plaintiff’s “telephone device” distinction
   could mean that Plaintiff’s claims against Defend-
   ants in the instant matter are not barred by col-
   lateral estoppel on the basis of the EarthLink
   Court’s denial of motions for judgment as a matter
   of law (“JMOL”) based on the absence of the “tele-
   phone” elements in EarthLink’s product. But that
   would only allow Plaintiff to overcome one of the
   bases on which it lost in EarthLink. Another rea-
   son a judgment of non-infringement was entered
   in that earlier action is that Plaintiff failed to
   show that industry standard ADSL was within
   the scope of the patents-in-suit.
    The court pointed out that in the EarthLink case, the
trial court ruled that, based on the impeachment of In-
line’s expert, a reasonable jury could have rejected In-
line’s theory that (1) EarthLink used the industry
standard ADSL and (2) the industry standard ADSL
infringed the asserted patents. The Earthlink court’s
ruling on that point, the district court concluded, consti-
tuted a “second, independent basis for the finding of non-
infringement in EarthLink.” According to the district
court, that second ground supporting the denial of Inline’s
JMOL motion was fatal to United’s claims in this case,
because under Third Circuit law “independently sufficient
alternative findings [are] given preclusive effect.” Upon
concluding that the question whether the industry stand-
ard ADSL infringes United’s patents was previously
adjudicated against United’s predecessor in the Earth-
Link case, the court held that collateral estoppel princi-
ples barred United from seeking to relitigate that issue in
this case.
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                            II
    On appeal, United argues that the district court mis-
applied the principles of collateral estoppel, as those
principles are applied by the Third Circuit.1 The essence
of United’s argument is as follows: The JMOL order in
the EarthLink case established only that the jury could
permissibly have reached its verdict on either of two
possible grounds—either that EarthLink’s system did not
infringe because it lacked a telephone or that the stand-
ard ADSL technology was not within the scope of the
patents in suit. The EarthLink JMOL decision therefore
did not establish that the jury necessarily based its ver-
dict on a conclusion that the standard ADSL technology
did not infringe United’s patents. Accordingly, it was
improper for the district court to hold that United is
collaterally estopped from litigating that issue in this
case.
    That analysis is correct. To be sure, United’s argu-
ment in the district court was not nearly as focused as it
is in this court. In fact, before the district court United
directed its argument in large measure to irrelevant
matters and barely alluded to the argument that it now
vigorously presses on appeal. However, after examining
the record of the proceedings before the district court, we
are satisfied that United preserved the argument that it
urges upon this court, although the lack of focus in Unit-
ed’s argument before the district court no doubt goes a


    1   In a case such as this one, involving general prin-
ciples of the law of judgments that do not implicate ques-
tions within this court’s exclusive jurisdiction, we apply
the law of the regional circuit, which in this case is the
Third Circuit. See Transocean Offshore Deepwater Drill-
ing, Inc. v. Maersk Contractors USA, Inc., 617 F.3d 1296,
1311 (Fed. Cir. 2010); Bayer AG v. Biovail Corp., 279 F.3d
1340, 1345 (Fed. Cir. 2002).
UNITED ACCESS TECHNOLOGIES     v. CENTURYTEL BROADBAND        7
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long way toward explaining why the district court erred in
its application of collateral estoppel in this case.
                               A
     A party seeking to apply the doctrine of collateral es-
toppel based on a prior action must show that (1) the
previous determination was necessary to the decision; (2)
the identical issue was previously litigated; (3) the issue
was actually decided in a decision that was final, valid,
and on the merits; and (4) the party being precluded from
relitigating the issue was adequately represented in the
previous action. Hawksbill Sea Turtle v. Fed. Emergency
Mgmt. Agency, 126 F.3d 461, 474-75 (3d Cir. 1997); Ste-
phen Slesinger, Inc. v. Disney Enters., Inc., 702 F.3d 640,
644 (Fed. Cir. 2012); Laguna Hermosa Corp. v. United
States, 671 F.3d 1284, 1288 (Fed. Cir. 2012); 18 Charles
Alan Wright, Arthur R. Miller & Edward H. Cooper,
Federal Practice & Procedure § 4416, at 392 (2002); Re-
statement (Second) of Judgments § 27 (1982); see generally
Brown v. Felsen, 442 U.S. 127, 139 n.10 (1979)
(“[C]ollateral estoppel treats as final only those questions
actually and necessarily decided in a prior suit.”). In this
case, we focus on the third of those requirements: whether
the issue in dispute was actually decided in the prior
action. We conclude that the issue in dispute—whether
standard ADSL infringes the asserted claims of United’s
patents—was not actually decided in the EarthLink case.
    To address this issue, we must consider the principles
of collateral estoppel that apply in the context of a general
jury verdict. It is well established that a general jury
verdict can give rise to collateral estoppel only if it is clear
that the jury necessarily decided a particular issue in the
course of reaching its verdict. See Ashe v. Swenson, 397
U.S. 436, 444 (1970). When there are several possible
grounds on which a jury could have based its general
verdict and the record does not make clear which ground
the jury relied on, collateral estoppel does not attach to
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any of the possible theories. Id.; see Novartis Pharm.
Corp. v. Abbott Labs., 375 F.3d 1328, 1334 (Fed. Cir.
2004) (no collateral estoppel because there was a general
jury verdict and “no record evidence explaining the jury’s
rationale for its verdict”; the defendant therefore failed to
satisfy its burden of showing that the jury necessarily
relied on the district court’s construction of a particular
term in the patent); Chew v. Gates, 27 F.3d 1432, 1438
(9th Cir. 1994) (“Where the prior judgment was based on
a general verdict, the inquiry is whether rational jurors
must necessarily have determined the issue as to which
estoppel is sought.”); Tucker v. Arthur Andersen & Co.,
646 F.2d 721, 729 (2d Cir. 1981) (when a general verdict
has been rendered in favor of a defendant, “[i]f several
issues have been litigated, it is not known what factual
issues the jury has decided, for the defendant was entitled
to the verdict if the plaintiff failed to persuade the jury as
to any element of his claim”).
    When a court seeks to determine what issues were
necessarily decided by the jury, the party asserting pre-
clusion bears the burden of showing “with clarity and
certainty what was determined by the prior judgment.”
Jones v. City of Alton, Ill., 757 F.2d 878, 885 (7th Cir.
1985); see also Connors v. Tanoma Min. Co., 953 F.2d 682,
684 (D.C. Cir. 1992); Davis & Cox v. Summa Corp., 751
F.2d 1507, 1518 (9th Cir. 1985). Where there is doubt as
to the issue or issues on which the jury based its verdict,
collateral estoppel is inapplicable. See S.E.L. Maduro
(Fla.), Inc. v. M/V Antonio de Gastaneta, 833 F.2d 1477,
1483 (11th Cir. 1987) (“If the jury could have premised its
verdict on one or more of several issues, then collateral
estoppel does not act as a bar to future litigation of the
issues.”); C.B. Marchant Co. v. Eastern Foods, Inc., 756
F.2d 317, 319 (4th Cir. 1985) (holding that it was impossi-
ble to determine from the general verdict in a prior action
what theory the jury had relied on to award damages;
“[b]ecause of the existence of alternative bases of liability,
UNITED ACCESS TECHNOLOGIES   v. CENTURYTEL BROADBAND      9
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it cannot be shown that the proof of a de facto merger was
necessary and essential to the judgment.”); N.J.-Phila.
Presbytery of the Bible Presbyterian Church v. N.J. State
Bd. of Higher Educ., 654 F.2d 868, 876 (3d Cir. 1981) (“[I]f
the judgment is based on one or more of several grounds,
but does not expressly rely on any of them, none is conclu-
sively established, since a subsequent court cannot tell
what issue or issues were in fact fully adjudicated.”)
(applying New Jersey law).
     In its 1876 decision in Russell v. Place, 94 U.S. 606
(1876), the Supreme Court dealt with a case roughly
analogous to this one and set out the principles that
govern our decision in this case. In Russell, a patentee
obtained a jury verdict for patent infringement, upon
which judgment was entered. The verdict was obtained
over a defense of patent invalidity. The patentee later
filed a second action on the same patent against the same
defendant and sought to invoke the judgment in the first
case to estop the defendant from asserting patent invalid-
ity in the second case. The Supreme Court held that
collateral estoppel was not available, because of uncer-
tainty as to the scope of the verdict in the first case.
    The Russell Court ruled that in order for collateral es-
toppel to apply,
   it must appear, either upon the face of the record
   or be shown by extrinsic evidence, that the precise
   question was raised and determined in the former
   suit. If there be any uncertainty on this head in
   the record—as, for example, if it appear that sev-
   eral distinct matters may have been litigated up-
   on one or more of which the judgment may have
   passed, without indicating which of them was
   thus litigated, and upon which the judgment was
   rendered—the whole subject-matter of the action
   will be at large, and open to a new contention, un-
   less this uncertainty be removed by extrinsic evi-
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     dence showing the precise point involved and de-
     termined.
94 U.S. at 608. Because the initial action had been tried
on two claims, and it was unclear whether the jury had
based its liability decision on only one of the two claims,
the Supreme Court held that “[t]he validity of the patent
was not necessarily involved, except with respect to the
claim which was the basis of the recovery.” Id. at 609.
Even though the Court acknowledged that the prior jury
might have found infringement based on either claim or
both, it held that the record lacked “that certainty which
is essential to its operation as an estoppel and does not
conclude the defendants from contesting the infringement
or the validity of the patent in this suit.” Id. Accordingly,
the Court held that the jury’s verdict in the first action
was not entitled to be given collateral estoppel effect in
the second.
                             B
    The district court in this case found that the jury
could have based its verdict in the EarthLink case on one
of two separate grounds—either that EarthLink did not
use a telephone in its system or that the standard ADSL
technology itself did not infringe. Normally, the court’s
finding that the verdict could have been based on alterna-
tive grounds would be sufficient to render collateral
estoppel unavailable. The court, however, ruled that
collateral estoppel was available to the defendants be-
cause the trial court in the EarthLink case had held, in
response to the plaintiff’s JMOL motion, that the jury’s
verdict could be sustained on either of the two theories of
noninfringement that were presented to it. The defend-
ants argued to the district court, and continue to argue
here, that under Third Circuit law, if there are alternative
grounds for a decision, collateral estoppel can apply to
both of them. The defendants principally rely on the
holding in Jean Alexander Cosmetics, Inc. v. L’Oreal
UNITED ACCESS TECHNOLOGIES    v. CENTURYTEL BROADBAND     11
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USA, Inc., 458 F.3d 244 (3d Cir. 2006), for that proposi-
tion.
    The problem with the defendants’ argument is that it
is based on a principle that applies to a situation very
different from the one at issue here. The Jean Alexander
case on which the defendants rely involved a decision by
an adjudicator in the first case that was explicitly based
on two alternative grounds. That means that the adjudi-
cator actually considered both grounds and regarded each
as independently sufficient to justify the conclusion
reached. In that setting, it is reasonable to conclude that
collateral estoppel effect should be granted to either of the
adjudicator’s alternative holdings. In Jean Alexander, the
court had before it a prior ruling of the Trademark Trial
and Appeal Board (“TTAB”) dismissing L’Oreal’s petition
to cancel Jean Alexander’s registration of a trademark.
The prior ruling was explicitly based on two independent
grounds—priority and lack of likelihood of confusion. The
question before the court was whether, in light of the two
independent grounds for decision, either one would be
entitled to collateral estoppel effect. The court held that
in such a case both rulings are entitled to preclusive
effect. In so doing, the Third Circuit adopted a position
that had been endorsed in the First Restatement of
Judgments, but rejected in the Second Restatement of
Judgments, and on which there is a split among the
circuits.
    The First Restatement of Judgments took the position
that where the decision of the first tribunal rests on
alternative grounds, collateral estoppel can apply to each
of the alternative grounds recited. Restatement of Judg-
ments § 68 cmt. n (1942) (“Where the judgment is based
upon the matters litigated as alternative grounds, the
judgment is determinative on both grounds, although
either alone would have been sufficient to support the
judgment.”). In the Second Restatement of Judgments,
the American Law Institute changed its position and
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adopted the view that, where the decision of the first
tribunal rests on alternative grounds, none of those
grounds is entitled to be accorded collateral estoppel
effect. Restatement (Second) of Judgments § 27 cmt. i (“If
a judgment of a court of first instance is based on deter-
minations of two issues, either of which standing inde-
pendently would be sufficient to support the result, the
judgment is not conclusive with respect to either issue
standing alone.”).
     The rationale underlying the First Restatement’s po-
sition is that when the first tribunal has expressly adopt-
ed alternative grounds for a decision, it has
unambiguously determined that each of those grounds is
sufficient to justify its decision, and the fact that there are
other grounds that also support the decision should not
undermine the preclusive effect of the decision on the
issue in dispute. The rationale of the Second Restate-
ment’s position is that when a tribunal decides a case
based on alternative grounds, none of them is strictly
necessary to the decision, and it is possible that less
attention was paid to each than would be the case if the
decision rested on a single ground.2
   The defendants contend that this case turns on the is-
sue that divided the two Restatements, and that this


     2 Several circuits, in addition to the Third Circuit,
have adopted the First Restatement’s position. See, e.g.,
Gelb v. Royal Globe Ins. Co., 798 F.2d 38, 45 (2d Cir.
1986); In re Westgate-Cal. Corp., 642 F.2d 1174, 1176-77
(9th Cir. 1981). Other circuits have adopted the position
of the Second Restatement. See, e.g., In re Microsoft Corp.
Antitrust Litig., 355 F.3d 322, 328 (4th Cir. 2004); Pea-
body Coal Co. v. Spese, 117 F.3d 1001, 1008 (7th Cir.
1997) (en banc); Soc’y of Separationists, Inc. v. Herman,
939 F.2d 1207, 1213-14 n.25 (5th Cir. 1991); Turney v.
O’Toole, 898 F.2d 1470, 1472 n.1 (10th Cir. 1990).
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court is obliged to follow the Third Circuit’s position
adopting the First Restatement’s view. In so arguing, the
defendants necessarily contend that the Earthlink JMOL
ruling is analogous to the TTAB decision in the Jean
Alexander case. But that contention is mistaken. The
decision of the prior tribunal in Jean Alexander was an
explicit ruling that two independent grounds supported
the tribunal’s decision in the first case. By contrast, the
court’s JMOL ruling in the EarthLink case was simply a
decision that a rational jury could reasonably have found
non-infringement based on either of two theories. The
JMOL ruling did not hold that the jury had, in fact,
decided in favor of EarthLink on both of those grounds.
    That difference is dispositive. The application of col-
lateral estoppel depends on the second court’s concluding
that the issue in dispute was clearly resolved by the first
tribunal. That was true in the Jean Alexander case, but
not in the EarthLink case, where the trial court’s decision
on JMOL was simply that the jury could reasonably have
concluded that the standard ADSL system did not in-
fringe, not that the jury necessarily did so conclude.
     The defendants’ argument that a ruling as to the suf-
ficiency of the evidence on multiple grounds provides a
basis for invoking collateral estoppel on each of those
grounds is squarely contrary to the reasoning of one of the
Supreme Court’s leading decisions on collateral estoppel,
Ashe v. Swenson, 397 U.S. 436 (1970). In Ashe, the Court
explained that in determining the collateral estoppel
effect, if any, of a general jury verdict, the court must
decide “whether a rational jury could have grounded its
verdict upon an issue other than that which the defendant
seeks to foreclose from consideration.” Id. at 444. The
Court held that if the jury could have based its verdict on
a ground other than the one in dispute, collateral estoppel
would not bar litigation of the disputed issue. See Schiro
v. Farley, 510 U.S. 222, 233 (1994).
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    That is exactly the situation in this case: In holding
that the jury verdict in the EarthLink case could have
been based on the absence of a telephone from Earth-
Link’s systems, rather than on the failure of proof that
the ADSL technology infringes United’s patents, the trial
court in EarthLink found that a rational jury could have
grounded its verdict on an issue other than the one the
defendants now seek to foreclose from consideration—
precisely the finding that the Supreme Court in Ashe held
to be fatal to an effort to apply collateral estoppel to the
jury’s verdict.
    The defendants’ theory of collateral estoppel is also
contrary to a Supreme Court decision from a century and
a half ago, Packet Co. v. Sickles, 72 U.S. 580 (1866). In
that case, the plaintiff sued the defendant on four counts,
including the first and fourth counts, which involved two
different contracts. The jury returned a general verdict in
favor of the plaintiff, but without specifying whether its
verdict was based on the contract in the first count or the
contract in the fourth count.
    In a later action brought by the plaintiff on the con-
tract that had been asserted in the first count of the first
action, the plaintiff sought to estop the defendant from
asserting the invalidity of the contract as a defense. The
Supreme Court rejected the plaintiff’s claim. The Court
observed that the record of the first case showed that the
evidence “was sufficient to have justified the jury in
finding either contract.” Sickles, 72 U.S. at 591. None-
theless, the Court concluded that because the jury “might
have found in favor of the plaintiffs on the contract as set
forth in the fourth count, even if they disbelieved the
proof of the agreement [set forth in the first count],” id. at
591-92, the jury’s verdict could not be erected as an estop-
pel against the defendant’s challenge to the contract
asserted in the first count. The Court explained that
“even where it appears from the extrinsic evidence that
the matter was properly within the issue controverted in
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the former suit, if it be not shown that the verdict and
judgment necessarily involved its consideration and
determination, it will not be concluded.” Id. at 592. Thus,
even though the Court in the Sickles case held that the
evidence was sufficient to support a verdict on either
theory of liability raised in the first action, the Supreme
Court held that collateral estoppel did not apply because
“it is quite clear that the record of the former trial, to-
gether with the extrinsic proofs, failed to show that the
contract in controversy in the present suit was necessarily
determined in the former in behalf of the plaintiffs.” Id.
    The Supreme Court’s decision in the Sickles case can-
not be squared with the district court’s decision here. In
Sickles, as here, the first jury could have based its finding
of liability on either (or both) of two possible grounds.
The Court in Sickles, like the trial court in EarthLink,
found that the evidence was sufficient to support the
jury’s verdict on either ground. Nonetheless, the Sickles
Court held that because it was not clear that the first jury
decided the case on the ground presented in the second
action, collateral estoppel was inapplicable. Applying the
same analysis here requires that we reverse the district
court’s decision applying collateral estoppel against
United.
                             C
    The defendants argue that United waived its right to
argue that the “same issue” was not presented in the first
and second actions in this case, because it failed to identi-
fy any material difference between the systems accused in
the two cases. That argument misses the point. The
question before this court is not whether there is a differ-
ence between the ADSL system sold by EarthLink and
the ADSL system sold by the defendants. Instead, assum-
ing the two accused ADSL systems share the same indus-
try standard ADSL technology, the question is whether
the jury in the EarthLink case necessarily decided that
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the standard ADSL technology infringed the asserted
claims. If it is not known whether the EarthLink jury
found that the standard ADSL technology infringed, it
does not matter whether the two systems are the same or
not. That is because, if the jury did not necessarily decide
that the standard ADSL technology did not infringe the
asserted claims, there is no decision in the first case to
which collateral estoppel can be applied in this one.
    There may be other grounds on which the defendants
in this case can prevail without the need for a trial, and
our opinion does not foreclose the district court from
addressing any such grounds, if they exist. We hold only
that it was error to apply collateral estoppel to a general
jury verdict that could have rested on multiple grounds,
simply because the first court held, in its JMOL ruling,
that the evidence would have been sufficient to support
the jury’s verdict on either theory of liability presented to
it.
            REVERSED AND REMANDED
