Halo Electronics, Inc. v. Pulse Electronics, Inc., Fka Pulse Engineering, Inc., Pulse Electronics Corporation,…

N OTE: This disposition is nonprecedential.
United States Court of Appeals
for the Federal Circuit
______________________
HALO ELECTRONICS, INC.,
Plaintiff-Appellant
v.
PULSE ELECTRONICS, INC., FKA PULSE
ENGINEERING, INC., PULSE ELECTRONICS
CORPORATION, FKA TECHNITROL, INC.,
Defendants-Cross-Appellants
______________________
2023-1772, 2023-1966
______________________
Appeals from the United States District Court for the
District of Nevada in No. 2:07-cv-00331-APG-PAL, Judge
Andrew P. Gordon.
______________________
Decided: February 28, 2025
______________________
J OHN A. D RAGSETH , Fish & Richardson P.C., Minneap-
olis, MN, argued for plaintiff-appellant. Also represented
by MICHAEL J. K ANE.
W. WEST ALLEN, Howard & Howard Attorneys PLLC,
Las Vegas, NV, argued for defendants-cross-appellants.
Also represented by JONATHAN F. K ARMO, Royal Oak, MI.
______________________
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HALO ELECTRONICS, INC. v. PULSE ELECTRONICS , INC. 2
Before P ROST , BRYSON, and REYNA, Circuit Judges.
BRYSON, Circuit Judge.
This 18-year-old patent infringement action comes
before this court for the fifth time. The patentee, plaintiff
Halo Electronics, Inc. (“Halo”), appeals from the district
court’s denial of its motion for enhanced damages and
attorney fees, and from the district court’s denial of a new
trial on damages. The defendants, Pulse Electronics, Inc.
and Pulse Electronics Corporation (collectively, “Pulse”)
cross-appeal from the district court’s award of prejudgment
interest. We affirm the district court’s denial of the motion
for enhanced damages and attorney fees, as well as the
court’s denial of the motion for a new damages trial. We
vacate the district court’s award of prejudgment interest
and remand to the district court to re-calculate the interest
due to Halo as directed in this opinion.
I
Halo brought this lawsuit against Pulse in 2007, and
the case went to trial in 2012. The jury found direct and
induced infringement of several of Halo’s asserted patent
claims, and it found that Pulse’s infringement was willful.
App. 531–39. The jury awarded a total of $1.5 million as
damages for Pulse’s infringement. App. 541.
On May 28, 2013, the district court entered judgment
against Pulse in the amount of $1.5 million. Dkt. No. 523.
Although Halo sought an award of enhanced damages
under 35 U.S.C. § 284, the district court found that Halo
did not prove by clear and convincing evidence that Pulse
acted despite an objectively high risk of infringement, a
required predicate for enhancement by then-controlling
precedent. Dkt. No. 522. Halo sought review of the May
28, 2013, judgment, which ultimately led to a Supreme
Court decision that articulated a new standard for
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HALO ELECTRONICS, INC. v. PULSE ELECTRONICS , INC. 3
awarding enhanced damages. See Halo Elecs., Inc. v. Pulse
Elecs., Inc., 579 U.S. 93 (2016).
In July 2015, while this case was pending before the
Supreme Court, Halo filed a motion in the district court
seeking supplemental damages for direct infringement
between June 2012 and October 2013. Halo also requested
that the district court order Pulse to produce data that
could be used to assess supplemental damages for induced
infringement during that period. Dkt. No. 582. At the
same time, Halo moved for an award of pre- and post-
judgment interest on the $1.5 million judgment and on the
supplemental damages. Id.
On April 6, 2016, the district court awarded Halo
$388,043 in supplemental damages for direct infringement
and ordered Pulse to produce data that Halo could use to
assess supplemental damages for induced infringement.
Dkt. No. 591 at 1. The district court also awarded Halo
prejudgment interest at the rate set forth in Nev. Rev. Stat.
§ 17.130, compounded annually, through May 28, 2013,
and post-judgment interest from May 28, 2013, at the rate
set forth in 28 U.S.C. § 1961. Id. The district court directed
Halo to prepare an updated calculation of the total amount
of interest due and to provide that calculation to Pulse. The
parties disagreed on that calculation and submitted briefs
to the district court addressing that issue. Dkt. Nos. 592,
593.
Before the district court determined which calculation
of the interest would be used, however, Pulse appealed the
order stating that interest would be awarded. This court
dismissed that appeal in May 2017 because the order from
which the appeal was taken was not final. Halo Elecs., Inc.
v. Pulse Elecs., Inc., 857 F.3d 1347, 1351 (Fed. Cir. 2017)
(holding that the April 6, 2016, order was not final because
“[t]he district court never resolved the parties’ dispute
regarding the date from which to begin calculating
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HALO ELECTRONICS, INC. v. PULSE ELECTRONICS , INC. 4
prejudgment interest or set the amount of prejudgment
interest to be awarded to Halo”).
In August 2016, while Pulse’s appeal from the order
regarding prejudgment interest was pending, we vacated
the unenhanced damages award and remanded the case for
the district court to determine whether an award of
enhanced damages was appropriate in light of the Supreme
Court’s Halo decision. Halo Elecs., Inc. v. Pulse Elecs., Inc.,
831 F.3d 1369 (Fed. Cir. 2016). In every other respect,
however, we affirmed the May 28, 2013, judgment of the
district court. Id.
On September 27, 2016, the district court held a status
conference to discuss post-remand proceedings. See Dkt.
No. 605. A few weeks later, Halo filed a motion for
enhanced damages and attorney fees. App. 756–85. While
that motion was pending, the parties filed a stipulation
acknowledging that Pulse had paid the full amount of the
$1.5 million judgment entered against it in 2013. Dkt. No.
612 at 2. The parties further stipulated that Pulse had
paid $47,500 for supplemental inducement damages and
$6,131.76 for “post-judgment interest from the date of
entry of judgment through and including November 16,
2016.” Id. The stipulation referred to the post-judgment
interest issue as “resolved,” but excluded prejudgment
interest. Id. The stipulation did not expressly refer to the
award of $388,043 in supplemental damages for direct
infringement. The district court approved the stipulation
on November 21, 2016.
On September 6, 2017, the district court denied Halo’s
motion for enhanced damages and attorney fees. App. 11–
23. The order did not address the amount of prejudgment
interest to be awarded to Halo. The order nevertheless
stated that “the clerk of the court shall enter judgment
accordingly and close this case.” App. 23. The same day,
the clerk entered a document with the heading, “Judgment
in a Civil Case,” which stated: “[J]udgment has been
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HALO ELECTRONICS, INC. v. PULSE ELECTRONICS , INC. 5
entered pursuant to [the September 6, 2017] Order. See
Order for details.” App. 24.
Following the clerk’s entry of judgment and the order
closing the case, nothing happened for nearly three years.
Then, on July 30, 2020, Halo filed a motion seeking
prejudgment interest and a new damages trial. App. 1615–
35. Halo pointed out that the district court had not made
a final ruling on the issue of prejudgment interest. As for
damages, Halo argued that WesternGeco LLC v. ION
Geophysical Corp., 585 U.S. 407 (2018), was intervening
case law that permitted it to seek additional damages for
Pulse’s activities outside the United States. App. 1619.
The district court denied the July 2020 motion as
untimely, App. 10, and Halo took an appeal from that
order. We dismissed that appeal, holding that the
judgment entered on September 6, 2017, was not a final
judgment because the district court had not decided the
amount of prejudgment interest to be awarded. See Halo
Elecs., Inc. v. Bel Fuse, Inc., 2021-1861, 2022 WL 1435382,
at *3 (Fed. Cir. 2022). We noted that “[i]n the event of
further proceedings in this case, the district court will have
the discretion either to adjudicate the amount of
prejudgment interest to be awarded to Halo or to consider
whether to terminate the proceedings on Halo’s request for
prejudgment interest and any further relief based on
Halo’s failure to prosecute after September 2017.” Id.
(citing Fed. R. Civ. P. 41(b) and Link v. Wabash R. Co., 370
U.S. 626, 630–31 (1962)).
On remand, Pulse requested that the court terminate
all proceedings under Federal Rule of Civil Procedure
41(b). Dkt. No. 660. Following briefing of that issue, the
district court on March 7, 2023, entered an order awarding
“a limited amount of prejudgment interest.” App. 1. How-
ever, the court denied Halo’s request for a new trial on ad-
ditional damages. Id.
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HALO ELECTRONICS, INC. v. PULSE ELECTRONICS , INC. 6
On March 27, 2023, the district court entered judgment
against Pulse in the amount of $3,182,049.62, which con-
sisted of the $1.5 million damages awarded by the jury,
$388,043 in supplemental damages for direct infringement,
and $1,294,006.62 in prejudgment interest. See App. 2554;
Dkt. No. 668. Both parties have appealed from that judg-
ment.
II
Halo’s first claim on appeal is that the district court
should have granted its request for enhanced damages.1
After considering the evidence submitted by the parties,
the district court found that Pulse’s infringement was not
“so egregious and unusual that enhanced damages are
needed here.” App. 19. Halo argues that the court’s refusal
to award enhanced damages was an abuse of discretion be-
cause the district court “reject[ed] the jury’s findings on
Pulse’s intent,” and the failure to “accept all explicit and
implicit findings of the jury on a defendant’s intent” vio-
lates the Seventh Amendment. Halo’s Br. at 18.
We review a district court’s decision regarding en-
hanced damages for an abuse of discretion. Ironburg
1 The district court also denied Halo’s request for an
award of attorney fees under 38 U.S.C. § 285 on the ground
that “the totality of the evidence reveals that Pulse did not
defend this case so unreasonably as to make it an excep-
tional case.” App. 22. Although Halo contends that the
district court erred in refusing to award “enhancement or
fees,” Halo’s Br. at 16, Halo does not make any argument
specific to the issue of attorney fees. At most, Halo sug-
gests (without citing support) that “a finding of willfulness
fully overlaps factually with multiple considerations in eq-
uitably deciding whether to enhance damages or award at-
torney fees.” Id. at 17. We therefore do not separately
address the district court’s denial of attorney fees.
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HALO ELECTRONICS, INC. v. PULSE ELECTRONICS , INC. 7
Inventions Ltd. v. Valve Corp., 64 F.4th 1274, 1300 (Fed.
Cir. 2023). “We may find an abuse of discretion on a show-
ing that the court made a clear error of judgment in weigh-
ing relevant factors or exercised its discretion based upon
an error of law or clearly erroneous factual findings.”
Ecolab, Inc. v. FMC Corp., 569 F.3d 1335, 1352 (Fed. Cir.
2009). We hold that the district court did not abuse its dis-
cretion in denying enhanced damages in this case.
A
Under 35 U.S.C. § 284, “the court may increase the
damages up to three times the amount found or assessed.”
Prior to the Supreme Court’s decision in Halo, we had held
that a plaintiff seeking enhanced damages had to establish
willful infringement, which in turn required a showing of
both objective and subjective recklessness. In re Seagate
Tech., LLC, 497 F.3d 1360, 1368–71 (2007). The Supreme
Court in Halo rejected the Seagate test in favor of a less
rigid standard granting substantial discretion to district
courts in determining whether to award enhanced dam-
ages. See Halo, 579 U.S. at 103 (“[T]he language [of section
284] contains no explicit limit or condition, and . . . the word
‘may’ clearly connotes discretion.”).
The Supreme Court explained that district courts are
permitted “to exercise their discretion in a manner free
from the inelastic constraints of the Seagate test.” Id. at
104. The exercise of discretion is to be guided instead by
principles “developed over nearly two centuries of applica-
tion and interpretation of the Patent Act . . . limiting the
award of enhanced damages to egregious cases of miscon-
duct beyond typical infringement.” Id. at 110; see also id.
at 103 (“Awards of enhanced damages under the Patent Act
over the past 180 years establish that they are not to be
meted out in a typical infringement case, but are instead
designed as a ‘punitive’ or ‘vindictive’ sanction for egre-
gious infringement behavior.”). As Halo makes clear, how-
ever, “none of this is to say that enhanced damages must
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HALO ELECTRONICS, INC. v. PULSE ELECTRONICS , INC. 8
follow a finding of egregious misconduct.” Id. at 106. “As
with any exercise of discretion, courts should continue to
take into account the particular circumstances of each case
in deciding whether to award damages, and in what
amount.” Id.
Our case law has since emphasized that “[w]illfulness
and enhancement are separate issues,” Ironburg, 64 F.4th
at 1295, and that “an award of enhanced damages does not
necessarily flow from a willfulness finding,” Presidio Com-
ponents, Inc. v. Am. Tech. Ceramics Corp., 875 F.3d 1369,
1382 (Fed. Cir. 2017). Substantively, willfulness requires
“no more than deliberate or intentional infringement.” SRI
Int’l, Inc. v. Cisco Sys., Inc., 14 F.4th 1323, 1330 (Fed. Cir.
2021). Willfulness does not require “wanton, malicious,
and bad faith” conduct, of the sort that may warrant en-
hanced damages. See id.
Willfulness and enhancement also differ procedurally.
In a jury trial, willfulness is for the jury, while enhance-
ment is for the court once an affirmative finding of willful-
ness has been made by the jury. Eko Brands, 946 F.3d at
1378; see also WBIP, LLC v. Kohler Co., 829 F.3d 1317,
1341 (Fed. Cir. 2016) (“We do not interpret Halo as chang-
ing the established law that the factual components of the
willfulness question should be resolved by the jury.”).
“Questions of whether an accused patent infringer’s con-
duct was ‘egregious behavior’ or ‘worthy of punishment’”
are appropriate only at the enhancement stage. Eko
Brands, 946 F.3d at 1378.
B
Halo does not dispute that enhancement is discretion-
ary and that the jury’s finding of willfulness does not com-
pel the award of enhanced damages. See Halo’s Br. at 19–
20. Nonetheless, Halo argues that “a court ‘must’ start by
accepting the jury findings when considering enhance-
ment.” Id. at 21. For support, Halo quotes our statement
in SRI International that “we presume, as we must, that
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HALO ELECTRONICS, INC. v. PULSE ELECTRONICS , INC. 9
consistent with the court’s instructions, the jury found that
Cisco had no reasonable basis to believe that it did not in-
fringe or that it had a reasonable defense to infringement.”
14 F.4th at 1328.
Halo mischaracterizes that statement as having ad-
dressed the issue of enhancement. We referred to the jury’s
findings in SRI International because the district court had
granted judgment as a matter of law of no willful infringe-
ment, and the question before us was whether substantial
evidence supported the jury’s finding of willful infringe-
ment. See id. at 1330 (“Under the proper test for willful-
ness, and considering the presumed jury findings above, we
conclude that substantial evidence supports the jury’s will-
ful infringement finding. We thus reverse the district
court’s JMOL of no willful infringement and reinstate the
jury verdict of willful infringement.”). SRI International
does not support Halo’s argument that there are explicit or
implicit jury findings that bind the district court when ex-
ercising its discretion on enhancement.
Nor does this case touch on the Seventh Amendment
principle that when a jury verdict and a court ruling in the
same case turn on the same issue, the court must defer to
the jury’s resolution of that issue. See, e.g., Beacon Thea-
tres, Inc. v. Westover, 359 U.S. 500 (1959). As this court has
made clear, once there is a finding of willfulness, enhance-
ment requires the district court to answer a further ques-
tion about the egregiousness of the defendant’s misconduct
under the totality of circumstances. See SRI International,
14 F.4th at 1330; Presidio Components, 875 F.3d at 1382;
WBIP, 829 F.3d at 1341 n.13. This case is unlike Los An-
geles Police Protective League v. Gates, 995 F.2d 1469,
1473–74 (9th Cir. 1993), the case that Halo primarily relies
on, where the sole reason provided for the district court’s
equitable decision contradicted a fact that was specifically
implied from the jury’s verdict.
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HALO ELECTRONICS, INC. v. PULSE ELECTRONICS , INC. 10
Halo argues that the district court’s decision is irrecon-
cilable with the jury’s verdict on willfulness, but that is not
so.2 Acknowledging the jury’s finding of willful infringe-
ment, the district court correctly noted that the jury’s find-
ing was “but one factor” in determining whether “this is a
‘rare’ case warranting extraordinary punishment for a de-
fendant.” App. 19. Nor did the court reject the jury’s will-
fulness verdict by considering “evidence that [Pulse] had a
basis to believe that it was not infringing Halo’s patent or
that the patent was invalid during the relevant time peri-
ods when it was infringing.” App. 21. Consideration of
such evidence suggests that the court regarded the issue of
Pulse’s reckless disregard as a close question that did not
warrant enhanced damages. See Sunoco Partners Mktg. &
Terminals L.P. v. U.S. Venture, Inc., 32 F.4th 1161, 1177
(Fed. Cir. 2022) (listing “the closeness of the case” as a fac-
tor that may guide the court in the enhancement analysis).
According to the district court, there was “significant
evidence suggesting that at the relevant times when it in-
fringed, Pulse believed that Halo’s patents were invalid or
not infringed.” App. 19. The court cited “evidence that
Pulse created several similar transformer designs through-
out the 1980s and 1990s,” and that “Pulse submitted draw-
ings prepared by one of its engineers in 1997, which
2 The jury found that it was “highly probable that
Pulse’s infringement was willful.” App. 539. That finding
reflected the instruction that to prove willful infringement,
Halo had to prove that “prior to the filing date of the com-
plaint, Pulse acted with reckless disregard of the claims of
Halo’s patents.” Dkt. No. 470 at 18. The jury was further
instructed that to demonstrate “reckless disregard,” Halo
had to prove that “Pulse actually knew, or it was so obvious
that Pulse should have known, that Pulse’s actions consti-
tuted infringement of a valid patent.” Id.
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HALO ELECTRONICS, INC. v. PULSE ELECTRONICS , INC. 11
disclosed this open design.”3 App. 20. The court also cited
the testimony of Pulse’s engineer that “he analyzed Halo’s
patent in 2002 and concluded that it was invalid,” a conclu-
sion that he shared with members of Pulse’s management
team. Id.
The district court further pointed out that when Halo
contacted Pulse about paying for a license, Halo told Pulse
it had “not yet reached any conclusive determination as to
whether [Pulse’s] products” were infringing Halo’s patents.
Id. The court remarked that “[i]f Halo itself was not sure
that Pulse’s products infringed Halo’s own patents, it is
hard to claim that Pulse subjectively knew it was infring-
ing at that time.” App. 20–21.
Finally, the district court noted that in our prior opin-
ion in the first Halo appeal, we held that “[t]he record
shows that although Pulse was ultimately unsuccessful in
challenging the validity of the Halo patents, Pulse did raise
a substantial question as to the obviousness of the Halo pa-
tents.” See App. 21 (quoting Halo Elecs., Inc. v. Pulse El-
ecs., Inc., 769 F.3d 1371, 1382 (Fed. Cir. 2014)).4
3 Contrary to Halo’s assertion, Halo’s Br. at 23, the
jury’s finding of willfulness does not imply a finding that
Pulse copied Halo’s inventions. See Ironburg, 64 F.4th at
1300 (“[T]he jury could have predicated its finding of willful
infringement on ‘deliberate or reckless disregard of plain-
tiff’s patent rights,’ . . . without necessarily finding that
[the defendant] copied [the plaintiff’s] patent claims.”).
4 The Supreme Court in Halo did not address whether
Pulse raised a substantial question as to obviousness. This
court has held, however, that after Halo, the objective rea-
sonableness of the accused infringer’s positions can still be
relevant for the district court to consider when exercising
its discretion” to enhance damages. WesternGeco L.L.C. v.
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HALO ELECTRONICS, INC. v. PULSE ELECTRONICS , INC. 12
In sum, based on “all of the circumstances and evi-
dence,” the district court held that Pulse’s infringement
was not “so egregious and unusual that enhanced damages
are needed here.” App. 19. The district court thus applied
the correct standard for enhancement under controlling
precedent, and there was no clear error in its factual find-
ings.
C
As a related but assertedly “independent error,” Halo
argues that the district court erred by relying on the two
opinion letters that Pulse obtained, which concluded that
Halo’s patents were invalid. Halo’s Br. at 25; see also App.
20. Halo argues that it was error for the court to consider
those letters because Pulse previously withheld them as
privileged. Halo’s Br. at 25. We agree that “[t]he privilege
which protects attorney-client communications may not be
used both as a sword and a shield.” Chevron Corp. v. Penn-
zoil Co., 974 F.2d 1156, 1162 (9th Cir. 1992). However, we
do not view the district court’s reliance on the opinion let-
ters as having affected Halo’s substantial rights. See 28
U.S.C. § 2111 (“On the hearing of any appeal or writ of cer-
tiorari in any case, the court shall give judgment after an
examination of the record without regard to errors or de-
fects which do not affect the substantial rights of the par-
ties.”). As explained above, there was considerable other
evidence of the closeness of the case that supported the
court’s ruling on enhanced damages.
We therefore hold that the district court did not abuse
its discretion by denying enhanced damages in this case.
ION Geophysical Corp., 837 F.3d 1358, 1363 (Fed. Cir.
2016), rev’d on other grounds, 585 U.S. 407 (2018).
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HALO ELECTRONICS, INC. v. PULSE ELECTRONICS , INC. 13
III
A
Federal Rule of Civil Procedure 41(b) provides that “[i]f
the plaintiff fails to prosecute . . . a defendant may move to
dismiss the action or any claim against it.” Applying Rule
41(b), the district court awarded Halo “a limited amount of
prejudgment interest.” App. 1. In addition, the court de-
nied Halo’s motion for a new trial for additional damages
that were not available at the time of the original trial in
the case. Id.
Halo argues that the district court erred with respect
to both issues. First, Halo argues that it was error to deny
a “limited trial” on Halo’s claim for additional damages at-
tributable to Pulse’s overseas activities. Halo’s Br. at 30.
Second, Halo argues that the district court “substantially
lessen[ed] the amount of interest due to Halo by ending in-
terest period in 2017 rather than 2023.” Id. Halo argues
that the amount of interest, if correctly calculated, would
be more than $2.3 million. Halo’s Reply Br. at 32.
In its cross-appeal, Pulse argues that the district court
should have denied prejudgment interest altogether for
Halo’s failure to prosecute under Rule 41(b). Pulse’s Br. at
23. In the alternative, Pulse argues that the court erred by
“(1) awarding prejudgment interest under Nev. Rev. Stat.
§17.130 instead of the annual treasury bill rate; (2) accept-
ing Halo’s calculations that ignore the incremental nature
of the damages period; and (3) permitting interest into
2017 even though . . . Pulse satisfied the judgment and all
post-judgment interest issues as of November 2016.” Id.
We apply regional circuit law to the review of motions
to dismiss. OIP Techs., Inc. v. Amazon.com, Inc., 788 F.3d
1359, 1362 (Fed. Cir. 2015). The Ninth Circuit reviews dis-
missals under Rule 41(b) for abuse of discretion. Applied
Underwriters, Inc. v. Lichtenegger, 913 F.3d 884, 890 (9th
Cir. 2019). The district court’s exercise of discretion under
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HALO ELECTRONICS, INC. v. PULSE ELECTRONICS , INC. 14
Rule 41(b) “should not be disturbed unless there is a defi-
nite and firm conviction that the court . . . committed a
clear error of judgment in the conclusion it reached upon
weighing of the relevant factors.” Morris v. Morgan Stan-
ley & Co., 942 F.2d 648, 652 (9th Cir. 1991).
“A Rule 41(b) dismissal must be supported by a show-
ing of unreasonable delay.” Omstead v. Dell, Inc., 594 F.3d
1081, 1084 (9th Cir. 2010). “In addition, the district court
must weigh the following factors in determining whether a
Rule 41(b) dismissal is warranted: (1) the public’s interest
in expeditious resolution of litigation; (2) the court’s need
to manage its docket; (3) the risk of prejudice to the defend-
ants; (4) the public policy favoring disposition of cases on
their merits and (5) the availability of less drastic sanc-
tions.” Id.
The district court analyzed each of those factors to deny
Halo’s motion for a new trial while resolving Halo’s out-
standing claim for prejudgment interest. As explained be-
low, we hold that the district court did not abuse its
discretion in denying the motion for a new trial or in
awarding prejudgment interest despite Halo’s unreasona-
ble delay. However, we disagree with the district court’s
calculation of the amount of prejudgment interest and re-
mand for an adjustment in the amount of the interest
award to Halo.
B
In April 2016, the district court awarded prejudgment
interest to Halo without determining the amount. While
Pulse’s appeal of the April 2016 order was pending, the dis-
trict court held its September 27, 2016, status conference.
The minute entry for that conference states: “The Court
makes preliminary remarks and a discussion ensues re-
garding whether or not the federal circuit’s decision will af-
fect the Court’s ruling on the motion for accounting and the
interest calculation. The Court will take this issue under
advisement and issue a written order.” Dkt. No. 605.
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HALO ELECTRONICS, INC. v. PULSE ELECTRONICS , INC. 15
When the district court closed the case a year later, in
September 2017, it still had not issued a written order on
the calculation of prejudgment interest. On October 8,
2017, Halo’s counsel stated in an email to Pulse’s counsel:
“[W]e should try to figure out whether a settlement is pos-
sible this week, and if not, contact the Court to have it
quantify the interest due.” Dkt. No. 662-1 at 2. Halo, how-
ever, did not file anything regarding the prejudgment in-
terest issue until July 30, 2020, nearly three years later.
Considering these facts under Rule 41(b), the district court
held that “Halo unreasonably delayed its renewed request
for prejudgment interest.” App. 2.
Halo argues that there was no failure to prosecute on
its part because it had fully briefed the prejudgment inter-
est issue and the district court had committed to entering
a “written order” in the September 2016 minute entry.
Halo’s Br. at 30. Halo also characterizes the September
2017 closing of the case as an “administrative closing” that
did not place any burden on Halo to protest that the case
had been closed without calculating prejudgment interest.
Halo cites Lehman v. Revolution Portfolio LLC, 166 F.3d
389, 392 (1st Cir. 1999), in support of its assertion that “it
is normal for a court to administratively close a case that
has pending briefing, and later re-open the case,” and that
administrative closings allow a court to get a motion “off
the court’s docket to avoid hassling from administrators.”
Id. at 31–32.
As the district court correctly noted, the September
2017 judgment and order closing the case was not an “ad-
ministrative closing.” App. 3 n.2. In Lehman, the order
that was deemed to have “administratively” closed the case
stated: “In order to avoid the necessity for counsel to ap-
pear at period status conferences, it is hereby ORDERED
that the above-entitled action be and hereby is dismissed
without prejudice to either party moving to restore it to the
docket if any further action is required upon completion
and termination of all bankruptcy or arbitration
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HALO ELECTRONICS, INC. v. PULSE ELECTRONICS , INC. 16
proceedings.” 166 F.3d at 381. The court’s order thus ex-
pressly left open the possibility of future proceedings,
which has been treated as an indication of an administra-
tive closing rather than a final judgment in the case. See
WRS, Inc. v. Plaza Ent., Inc., 402 F.3d 424, 426–27 (3d Cir.
2005) (treating an order as an administrative closing where
the order provided that the clerk shall “mark the above-
captioned case as closed” and added that “should further
proceedings therein become necessary or desirable, any
party may initiate the same in the same manner as if this
order had not been entered”) (emphasis in original); Mercer
v. Allegheny Ludlum Corp., 132 F.R.D. 38 (W.D. Pa. 1990).5
Nothing in the language of the September 2017 order
in this case contemplated the possibility of further proceed-
ings. To be clear, the district court was mistaken in its be-
lief that there were no remaining issues in the case. But
mistaken or not, the district court made clear that it re-
garded the case as over. Given Halo’s knowledge in Sep-
tember 2017 that the prejudgment interest issue remained
5 In Penn West Associates, Inc. v. Cohen, 371 F.3d 118
(3d Cir. 2004), cited by Halo, the court found that the order
in question constituted an “administrative closing” and did
not have the effect of entering final judgment in the case.
The court noted that the closing order, like the order in
Lehman, did not state that the court was entering judg-
ment, but merely directed the clerk to mark the case closed.
See id. at 121, 126. In this case, the district court specifi-
cally directed the clerk to “enter judgment” in the case,
App. 23, and the clerk did so in a document entitled “Judg-
ment in a Civil Case,” which stated that “judgment has
been entered” in accordance with the court’s September 6,
2017, order. Under those circumstances, the court’s order
cannot reasonably be interpreted as merely an “adminis-
trative closing.”
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HALO ELECTRONICS, INC. v. PULSE ELECTRONICS , INC. 17
unresolved, Halo unreasonably delayed filing its motion for
a new trial and for prejudgment interest until July 2020.6
C
In 2011, the district court granted Pulse’s motion for
summary judgment in which the court rejected Halo’s
argument that Pulse was liable for the overseas sales of the
allegedly infringing products. The court held that “liability
under [35 U.S.C.] § 271(a) requires infringing activity
within the United States” and that “Pulse is not liable for
direct infringement based on its sales of accused products
outside of the United States.” App. 481. In June 2018,
after the district court had closed this case, leaving only the
issue of prejudgment interest unresolved, the Supreme
Court decided WesternGeco LLC v. Ion Geophysical Corp.,
585 U.S. 407 (2018). Halo contends that WesternGeco is
contrary to the district court’s 2011 summary judgment
ruling and justifies a new trial on damages. Halo filed its
motion for a new trial on July 30, 2020.
6 In response to Pulse’s cross-appeal seeking dismissal
of the claim for prejudgment interest, Halo argues that “the
Ninth Circuit prevents dismissals under Rule 41(b) unless
a party has first been warned that dismissal is imminent
and still does not act.” Halo’s Reply Br. at 33. The Ninth
Circuit has explained, however, that dismissal without a
warning may be warranted under “egregious circum-
stances” or where the “harsh sanction of dismissal should
not have surprised [the] plaintiff.” Johnson v. U.S. Dep’t of
the Treasury, 939 F.2d 820, 825 (9th Cir. 1991) (citations
and internal quotation marks omitted).
Moreover, “there is no warning requirement when dis-
missal follows a noticed motion under Rule 41(b).” Morris,
942 F.2d at 652. We construe Pulse’s request to dismiss in
the joint status report as a motion to dismiss.
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HALO ELECTRONICS, INC. v. PULSE ELECTRONICS , INC. 18
Invoking Rule 41(b), the district court denied the
motion for a new trial on damages. The court explained
that if Halo “truly believed that it was entitled to ask for a
new trial, it should have moved shortly after” WesternGeco
was decided and not two years after that decision. App. 6
n.3. In addition to Halo’s unreasonable delay in raising the
issue, the district court found that every Rule 41(b) factor
weighed in favor of dismissal. Regarding prejudice to Pulse
in particular, the district court held that “it is likely that
another trial would create the need for additional discovery
and expert witnesses” and that “[e]ven new discovery may
not be sufficient as some of the acts giving rise to this
lawsuit occurred over 20 years ago, and witnesses’
memories no doubt have diminished.” App. 5.
Halo makes two arguments specific to its request for a
new damages trial. First, Halo argues that “both expert
and fact discovery were complete on the relevant damages
issue when the district court ruled against Halo on
summary judgment,” and thus “the parties will be able to
work off the already-generated record.” Halo’s Br. at 40.
Second, Halo argues that the district court “wholly ignores
that Halo could not raise the issue [of a new damages trial]
because the case was closed.” Id. at 41. Halo suggests that
it had to wait until “it became clearer that the district court
was probably not going to act on the motion [for
prejudgment interest], as it had committed to do.” Id.
Halo’s arguments fail to show that the district court
abused its discretion in denying Halo’s motion for a new
trial on damages. Halo’s contention that it could not
promptly move for a new trial on damages because the case
was closed makes no sense. The fact that the case was
closed did not discourage Halo from moving for a new
damages trial two years later, in July 2020. Nor was there
any reason for Halo to wait on the resolution of the
prejudgment interest issue before moving for a new
damages trial. Halo could have and should have moved
promptly after WesternGeco was decided, not two years
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HALO ELECTRONICS, INC. v. PULSE ELECTRONICS , INC. 19
later. Halo’s arguments are thus insufficient to create “a
definite and firm conviction that the court . . . committed a
clear error of judgment in the conclusion it reached upon
weighing of the relevant factors” under Rule 41(b). Morris,
942 F.2d at 652.
D
After finding that Halo unreasonably delayed its re-
newed request for prejudgment interest, the district court
nonetheless held that “Halo is entitled to prejudgment in-
terest at the rate set forth in Nev. Rev. Stat. § 17.130, com-
pounded annually, from the time of service of the summons
and complaint through September 6, 2017.” App. 7. We
hold that the district court did not abuse its discretion in
ruling that it should decide the prejudgment interest issue
despite Halo’s delay in raising it. However, we disagree
with the district court’s calculation of the prejudgment in-
terest and remand for the court to correct the amount of
interest owed to Halo.
Unreasonable delay is but one factor to consider under
Rule 41(b). Although Pulse argues that “[u]nreasonable
delay, standing alone, justifies dismissal of . . . Halo’s re-
quest for prejudgment interest,” Pulse does not cite any
case law holding that unreasonable delay requires dismis-
sal. See Pulse’s Br. at 20. Pulse cites only cases holding
that there is a rebuttable presumption of prejudice from
unreasonable delay. See Henderson v. Duncan, 779 F.2d
1421, 1423 (9th Cir. 1986); Anderson v. Air West, Inc., 542
F.2d 522, 524 (9th Cir. 1976).
Considering other Rule 41(b) factors, the district court
held that the prejudgment interest issue can now be re-
solved expeditiously, “without significant additional ef-
fort,” and that “[a]warding that interest now facilitates
resolution of the case on the merits.” App. 3–5. The district
court also found limited prejudice to Pulse in awarding
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HALO ELECTRONICS, INC. v. PULSE ELECTRONICS , INC. 20
prejudgment interest to Halo.7 App. 4. In light of those
factors, it was not an abuse of discretion for the district
court to grant Halo’s renewed request for prejudgment in-
terest, notwithstanding Halo’s unreasonable delay in re-
questing it.
The district court also did not err by awarding prejudg-
ment interest “at the rate set forth in Nev. Rev. Stat.
§ 17.130, compounded annually.” App. 7. Although the
district court did not explain its rationale for calculating
interest in that manner, the parties had briefed the issue
of interest calculation, and the court followed Halo’s pro-
posal, thus implicitly adopting Halo’s reasoning. See Dkt.
Nos. 582, 592, 593. We find no abuse of discretion in that
portion of the district court’s prejudgment interest award.
Contrary to Pulse’s contention, Torres v. Goodyear Tire
& Rubber Co., 317 P.3d 828, 831 (Nev. 2014), does not pro-
hibit the award of compound interest in this case. While
the Nevada Supreme Court in that case held that the Ne-
vada statute governing the computation of interest on judg-
ments ordinarily provides for simple interest, the statute
contains an exception for cases in which a different rate of
7 Pulse argues that the district court erroneously held
that “Pulse’s new owners purchased the company while the
case was on appeal” and thus “assumed the risk that addi-
tional litigation (and related fees, costs, and potential dam-
ages) could arise.” App. 4. But even though the case was
not on appeal when the new owners purchased Pulse in De-
cember 2018, see Pulse’s Br. at 19, Pulse knew as of October
2017 that “the prejudgment interest issue had not been re-
solved and Halo intended to pursue it,” App. 4. The district
court cited Pulse’s knowledge of the outstanding prejudg-
ment interest issue, which is supported by the record, as
another factor lessening any prejudice to Pulse from the
order awarding interest.
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HALO ELECTRONICS, INC. v. PULSE ELECTRONICS , INC. 21
interest is “specified in the judgment” as was the case here.
See Nev. Rev. Stat. § 17.130(2).
Whether prejudgment interest for patent infringement
“should be compounded or uncompounded [is] . . . left
largely to the discretion of the district court.” Bio-Rad
Lab’ys, Inc. v. Nicolet Inst. Corp., 807 F.2d 964, 969 (Fed.
Cir. 1986); see also Rite-Hite Corp. v. Kelley Co., 56 F.3d
1538, 1555 (Fed. Cir. 1995) (en banc) (“It has been recog-
nized that an award of compound rather than simple inter-
est assures that the patent owner is fully compensated.
However, the determination whether to award simple or
compound interest is a matter largely within the discretion
of the district court.” (citation and internal quotation
marks omitted)).
Pulse asserts that Laitram Corp. v. NEC Corp., 115
F.3d 947 (Fed. Cir. 1997), stands for the proposition that
district courts must use the Treasury bill in calculating
prejudgment interest unless there is “evidence that the pa-
tentholder would have borrowed money at a higher rate or
any causal connection between any borrowing and the loss
of use of money awarded because of the infringement.”
Pulse’s Br. at 24. That is not an accurate characterization
of our decision in Laitram. We merely concluded that on
the facts of that case the district court did not abuse its
discretion by using the Treasury bill rate. See 115 F.3d at
955.
Reviewing courts “afford district courts wide latitude
in the selection of interest rates, and have permitted the
use of statutory rates set by states, U.S. Treasury bill rates,
and the prime rate.” Schwendimann v. Arkwright Ad-
vanced Coating, Inc., 959 F.3d 1065, 1076 (Fed. Cir. 2020)
(internal quotation marks omitted); see also Uniroyal, Inc.
v. Rudkin-Wiley Corp., 939 F.2d 1540, 1545 (Fed. Cir. 1991)
(district court’s award of prejudgment interest at the prime
rate sustained in light of the “wide latitude” afforded to
trial courts in selecting interest rates); Datascope Corp. v.
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HALO ELECTRONICS, INC. v. PULSE ELECTRONICS , INC. 22
SMEC, Inc., 879 F.2d 820, 829 (Fed. Cir. 1989) (district
court’s choice of annual compounding and the interest rate
set by 28 U.S.C. § 1961 rather than the prime rate did not
violate the “substantial discretion” a district court has to
determine the interest rate in patent infringement cases).
Finally, we reject Pulse’s argument that the district
court erred by “assum[ing] that damages were all incurred
at the outset of the case.” Pulse’s Br. at 27. Pulse cites no
authority for its argument that the court’s failure to “ex-
plain why it was proper to ignore the incremental nature
of damages” is “necessarily an abuse of discretion.” Id. To
the contrary, as this court has explained, “[w]here a jury
awards a lump-sum amount as a compensation for in-
fringement, the prejudgment interest is properly applied to
the entire amount beginning on the first date of the in-
fringement.” Schwendimann, 959 F.3d at 1076. The ra-
tionale for that rule is that the patentee should be placed
in “as good a position as he would have been in had the
infringer entered into a reasonable royalty agreement” at
the outset of the infringement. General Motors Corp. v.
Devex Corp., 461 U.S. 648, 655 (1983); see also Comcast IP
Holdings I LLC v. Sprint Commc’ns Co., 850 F.3d 1302,
1315 (Fed. Cir. 2017) (prejudgment interest assessed on
the entire royalty award where the jury awarded a lump-
sum amount).
The district court, however, did commit one error with
respect to interest by allowing prejudgment interest to ac-
crue until September 6, 2017. The district court’s award of
prejudgment interest up to the date of the 2017 judgment
was based on Halo’s suggestion of that date as a less drastic
measure than allowing prejudgment interest to accrue un-
til 2023. App. 6; see also App. 2480 (Halo’s briefing on Rule
41(b) at the district court). The district court held that the
proposal was “a fair resolution because [the September
2017] judgment should have included an award of prejudg-
ment interest,” and Halo’s unreasonable delay in raising
the issue after that should not be rewarded by including
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HALO ELECTRONICS, INC. v. PULSE ELECTRONICS , INC. 23
prejudgment interest to the date of the court’s March 7,
2023, order. App. 6. But rather than serving as a more
conservative award, the award actually created a windfall
for Halo.
The relevant judgment for purposes of calculating pre-
judgment interest with respect to the bulk of the damages
at issue is not the September 2017 judgment (nor the
March 2023 judgment, as Halo argues). We follow regional
circuit law in determining the relevant date of judgment
that “demarcates the boundary between pre- and post-
judgment interest.” Transmatic, Inc. v. Gulton Indus., Inc.,
180 F.3d 1343, 1347 (Fed. Cir. 1999). In the Ninth Circuit,
different rules apply depending on whether a case involves
only one “final, appealable” judgment or more. See Dish-
man v. UNUM Life Ins. Co. of Am., 269 F.3d 974, 990 (9th
Cir. 2001). In a case involving more than one judgment,
the relevant date of judgment is the date of the judgment
that “sufficiently ascertained” the damages at issue. Tins-
ley v. Sea-Land Corp., 979 F.2d 1382, 1383 (9th Cir. 1992);
see also Kaiser Aluminum & Chem. Corp. v. Bonjorno, 494
U.S. 827, 835–36 (1990) (“[T]he purpose of postjudgment
interest is to compensate the successful plaintiff for being
deprived of compensation for the loss from the time be-
tween the ascertainment of the damage and the payment
by the defendant.” (citation omitted)).
This case involves more than one final, appealable
judgment. The first was the May 2013 judgment for $1.5
million that Halo appealed in 2013. The other was the
March 2023 judgment that formed the basis for the present
appeal. The $1.5 million in damages were “sufficiently as-
certained” in May 2013. We vacated the May 2013 judg-
ment solely in order for the district court to determine
whether enhancement was appropriate. Halo, 831 F.3d at
1382. That limited purpose did not allow the $1.5 million
judgment to be reduced, as there was no evidentiary chal-
lenge to the corpus of the jury’s award.
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HALO ELECTRONICS, INC. v. PULSE ELECTRONICS , INC. 24
The district court therefore erred in awarding prejudg-
ment interest on the $1.5 million award for the period past
the date of the judgment for that amount, which was May
28, 2013. It was post-judgment interest, not prejudgment
interest, that accrued from May 28, 2013, until the date of
payment. Post-judgment interest under section 1961 ap-
plies not only to the amount of the judgment itself, but also
to any prejudgment interest that accrued on the judgment.
See Air Separation, Inc. v. Underwriters at Lloyd’s of Lon-
don, 45 F.3d 288, 291 (9th Cir. 1995) (“[P]ostjudgment in-
terest under 28 U.S.C. § 1961 applies to the prejudgment
interest component of a monetary award . . .. [F]ailure to
apply postjudgment interest to prejudgment interest would
result in the injured plaintiff bearing the cost resulting
from the loss of the use of money and would thereby reward
the defendant for having delayed satisfying the judg-
ment.”).8
8 When Pulse paid the $1.5 million judgment in No-
vember 2016, Pulse also paid $6,131.76 in post-judgment
interest and the parties stipulated that they had “resolved
the issue of post-judgment interest from the date of entry
of judgment through and including November 16, 2016.”
Dkt. No. 612 at 2. But given that the stipulation expressly
stated that the issue of prejudgment interest was not yet
resolved, it appears likely that Pulse’s November 2016 pay-
ment did not include post-judgment interest on the pre-
judgment interest it owed Halo.
It may be unnecessary, however, to make a separate
provision for the imposition of post-judgment interest on
the prejudgment interest that accumulated on the $1.5 mil-
lion award. The district court allowed compounding of the
prejudgment interest, which in effect imposes interest on
interest, thereby automatically compensating for the delay
in payment of the prejudgment interest. The district court
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HALO ELECTRONICS, INC. v. PULSE ELECTRONICS , INC. 25
E
As for the $388,043 in supplemental damages for direct
infringement that the district court awarded in April 2016,
no final, appealable judgment was entered including that
amount until March 2023. Nevertheless, the record sug-
gests that Pulse paid that amount on August 29, 2016, even
though the parties’ stipulation in November 2016 did not
expressly refer to that payment. See App. 2538. On re-
mand, the district court should determine whether the pay-
ment for those supplemental damages has been made and
on what date. If Pulse paid the $388,043 on August 29,
2016, as the records suggest may be the case, no interest
(whether pre- or post-judgment) may run past the date of
payment. We therefore vacate the award of prejudgment
interest up to September 6, 2017, and we direct that the
total amount owed to Halo be calculated based on the fore-
going analysis.
IV
To summarize, we affirm the district court’s various
rulings, except for its ruling on interest, which we vacate.
We remand to the district court for the limited purposes of
revising the award of interest to Halo and determining
whether the supplemental damages award for direct
infringement has been paid.
AFFIRMED IN PART, VACATED IN PART, AND
REMANDED
COSTS
No costs.
is in a better position than we are to make a conclusive de-
termination on that issue, which the court can address on
remand.
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