Court Opinion

ID: 9370403
Source: CourtListenerOpinion
Date Created: 2023-02-13 15:00:34.906497+00
Date Added: 2024-06-11T17:16:21.585239
License: Public Domain

Case: 21-2345    Document: 65     Page: 1   Filed: 02/13/2023

   United States Court of Appeals
       for the Federal Circuit
                  ______________________

                SSI TECHNOLOGIES, LLC,
                     Plaintiff-Appellant

                             v.

      DONGGUAN ZHENGYANG ELECTRONIC
             MECHANICAL LTD.,
            Defendant-Cross-Appellant
             ______________________

                   2021-2345, 2022-1039
                  ______________________

    Appeals from the United States District Court for the
 Western District of Wisconsin in No. 3:20-cv-00019-jdp,
 Judge James D. Peterson.
                 ______________________

                Decided: February 13, 2023
                 ______________________

     SHANE A. BRUNNER, Michael Best & Friedrich, LLP,
 Madison, WI, argued for plaintiff-appellant. Also repre-
 sented by MICHAEL BESS, Chicago, IL; J. RYAN GRAY, Ra-
 leigh, NC; MELANIE J. REICHENBERGER, Milwaukee, WI;
 DEREK C. STETTNER, Menomonee Falls, WI.

    JOSEPH KUO, Saul Ewing Arnstein & Lehr LLP, Chi-
 cago, IL, argued for defendant-cross-appellant. Also repre-
 sented by ELIZABETH A. THOMPSON.
                   ______________________
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 2                              SSI TECHNOLOGIES, LLC v.
         DONGGUAN ZHENGYANG ELECTRONIC MECHANICAL LTD.

 Before REYNA, BRYSON, and CUNNINGHAM, Circuit Judges.
 BRYSON, Circuit Judge.
     Appellant SSI Technologies, LLC, (“SSI”) brought this
 action against appellee Dongguan Zhengyang Electronic
 Mechanical LTD (“DZEM”), alleging that DZEM infringes
 two of SSI’s patents. DZEM asserted counterclaims for in-
 validity of the asserted patents and for tortious interfer-
 ence with prospective business relations. The district court
 granted summary judgment to DZEM on the infringement
 claims and dismissed DZEM’s invalidity counterclaims.
 The court also granted summary judgment to SSI on the
 tortious interference counterclaim. We affirm in part, re-
 verse in part, vacate in part, and remand.
                               I
                              A
     SSI has asserted U.S. Patent Nos. 8,733,153 (“the ’153
 patent”) and 9,535,038 (“the ’038 patent”) against DZEM in
 this case. The patents are generally directed to sensors for
 determining the characteristics of fluid in a container, such
 as a fuel tank. SSI’s commercial embodiments of the as-
 serted patents and DZEM’s accused products are systems
 that determine the quality and volume of diesel exhaust
 fluid (“DEF”) that is used in emission-reduction systems for
 diesel truck engines.
                              1
     Claim 1 is generally representative of the five asserted
 claims of the ’153 patent for purposes of this appeal. It re-
 cites:
     1. A system for determining a quality of a fluid in
     a tank, the system comprising:
     a transducer configured to generate a sound wave
     and to detect an echo of the sound wave, the trans-
     ducer positioned near the bottom of the tank such
     that the sound wave travels toward a fixed object,
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     the fixed object positioned a known distance away
     from the transducer;
     a temperature sensor configured to detect a tem-
     perature of the fluid; and
     a controller configured to
         produce a signal to drive the transducer to
         produce the sound wave,
         receive an indication of the detected echo
         from the transducer,
         receive an indication of the temperature of
         the fluid from the temperature sensor, and
         determine whether a contaminant exists in
         the fluid based on the temperature of the
         fluid, a time period from when the sound
         wave is produced to when the echo is de-
         tected, and at least one of the group of a)
         whether a measured volume is out of range
         and b) a dilution of the fluid is detected
         while the measured volume of the fluid de-
         creases.
 ’153 patent, cl. 1 (emphasis on disputed limitation).
      The specification of the ’153 patent describes an exem-
 plary sensor system containing two transducers, a “level”
 transducer and a “quality” transducer. Id. at col. 6, ll.
 5–12. The level transducer is positioned at the bottom of
 the tank and emits ultrasonic sound waves upward toward
 the surface of the fluid. Id. at Fig. 3 & col. 6, ll. 10–12. The
 quality transducer is positioned at the bottom of the tank
 and emits ultrasonic sound waves toward a reflector that
 is also positioned at the bottom of the tank. Id. at Fig. 3 &
 col. 6, ll. 8–10. Based on the time of flight of the sound
 wave emitted from the level transducer to the surface of
 the fluid, the system can calculate the volume of the fluid
 in the tank. Id. at col. 10, line 40, through col. 11, line 9.
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 Similarly, the system can determine the quality of the fluid
 (i.e., the concentration of the DEF) by using the time of
 flight of the sound wave, which is the elapsed time for the
 sound wave emitted from the quality transducer to travel
 to and back from the reflector. Id. at col. 9, ll. 17–50.
      The ’153 patent also discloses an error-detection mech-
 anism by which the system can “detect failures of various
 components of the system.” Id. at col. 12, ll. 38–40. First,
 the system can determine that an error exists “when it de-
 tects the concentration level of the [DEF] decreasing (i.e.,
 becoming diluted) at the same time as the level of the
 [DEF] is decreasing.” Id. at col. 12, ll. 40–43. Such condi-
 tions indicate an error “[b]ecause the [DEF] cannot become
 diluted when the level of the [DEF] is decreasing.” Id. at
 col. 12, ll. 51–53. Second, the system can determine that
 an error exists when “the calculated level [of DEF] will ex-
 ceed the known actual maximum level” of the tank. 1 Id. at
 col. 12, ll. 57–60.
                               2
     Claim 9 of the ’038 patent, the main claim of that pa-
 tent that is at issue in this appeal, recites:

     1    The specification of the ’153 patent uses the terms
 “measured” and “calculated” interchangeably. At one
 point, the specification discloses that the controller can per-
 form a “plausibility check” by “comparing the calculated
 level against the absolute physical capacity for the tank
 110.” ’153 patent, col. 11, ll. 34–38. In the following sen-
 tence, the specification notes that “[t]he controller 400 gen-
 erates a diagnostic output . . . whenever the measured
 level exceeds the capacity of the [DEF] tank.” Id. at col. 11,
 ll. 39–41. Those two sentences describe the same function-
 ality, and we therefore interpret the term “calculated,” as
 used in the ’153 patent, to be equivalent to the term “meas-
 ured.”
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     9. A sensor operable to sense a characteristic of a
     fluid, the sensor comprising:
     a sensing area configured to contain the fluid;
     a chimney configured to exhaust entrapped air
     from the sensing area; and
     a filter covering the sensing area, the filter config-
     ured to
         allow a liquid portion of the fluid to enter
         the sensing area, and
         substantially prohibit one or more gas bub-
         bles of the fluid from entering the sensing
         area; and
     a transducer configured to
         output a pulse of sound through the liquid
         portion of the fluid contained within the
         sensing area,
         receive the reflected pulse of sound, and
         output a characteristic of the fluid based on
         the received pulse of sound.
 ’038 patent, cl. 9 (emphasis on disputed limitation).
      Like the system disclosed in the ’153 patent, the sensor
 of the ’038 patent operates by measuring the time of flight
 of an “ultrasonic pulse wave [that] travel[s] the distance of
 the sensing area and return[s] to the output point.” Id. at
 col. 2, ll. 10–12. The invention of the ’038 patent seeks to
 address the problem of “erratic measurement results” that
 may occur due to “air bubbles [that] are embedded in the
 fluid.” Id. at col. 2, ll. 13–18. Accordingly, the specification
 of the ’038 patent discloses a sensor having a filter that
 “blocks, or inhibits, air bubbles from entering a sensing
 area of the fluid sensor.” Id. at col. 2, ll. 4–7.
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         DONGGUAN ZHENGYANG ELECTRONIC MECHANICAL LTD.

                               B
                               1
     The dispute in the district court regarding the ’153 pa-
 tent turned mainly on the limitation in claim 1 that recites
 a controller configured to
     determine whether a contaminant exists in the
     fluid based on the temperature of the fluid, a time
     period from when the sound wave is produced to
     when the echo is detected, and at least one of the
     group of a) whether a measured volume is out of
     range and b) a dilution of the fluid is detected while
     the measured volume of the fluid decreases.
 ’153 patent, cl. 1. The district court construed the second
 item of the Markush group in that limitation, “a dilution of
 the fluid is detected while the measured volume of the fluid
 decreases,” to require that the contaminant determination
 actually consider the measured volume of the fluid. SSI
 Techs., LLC v. Dongguan Zhengyang Elec. Mech. LTD, 559
 F. Supp. 3d 821, 829 (W.D. Wis. 2021). 2
     In support of its construction, the district court relied
 on the prosecution history of the ’153 patent. As the court
 observed, the inventors amended claim 1 during prosecu-
 tion to add the requirement that the controller base its con-
 tamination determination on “at least one of the group of
 a) whether a measured volume is out of range and b) a di-
 lution of the fluid is detected while the measured volume of
 the fluid decreases.” Id. at 829–30; J.A. 1093. The court
 concluded that the amendment to claim 1 was designed to

     2   The parties agreed that the first item of the
 Markush group, “whether a measured volume is out of
 range,” did not apply to DZEM’s accused sensors. SSI, 559
 F. Supp. 3d at 828.
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 incorporate the error-detection capability recited in the
 specification. SSI, 559 F. Supp. 3d at 829–30.
     In light of the court’s construction and the parties’
 agreement that DZEM’s accused sensor “doesn’t base the
 contamination determination on any consideration of the
 measured volume of the fluid,” the district court granted
 summary judgment that DZEM did not infringe the claims
 of the ’153 patent. Id. at 830.
                               2
      With respect to the ’038 patent, the dispute in the dis-
 trict court turned mainly on the district court’s construc-
 tion of the term “filter” and its application of that
 construction in its infringement analysis. The district
 court adopted DZEM’s proposed construction of “filter,”
 construing the term to mean “a porous structure defining
 openings, and configured to remove impurities larger than
 said openings from a liquid or gas passing through the
 structure.” Id. at 831–32.
      DZEM’s accused sensors include a rubber cover, which
 SSI argues is the filter recited in claim 9 of the ’038 patent.
 The rubber cover, shown below, has four small openings on
 its underside, each measuring approximately 2 millimeters
 by 10 millimeters.

 Id. at 833.
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 8                              SSI TECHNOLOGIES, LLC v.
         DONGGUAN ZHENGYANG ELECTRONIC MECHANICAL LTD.

      The district court held that DZEM did not infringe
 claim 9 because the rubber cover was not “porous” and
 therefore the accused sensors did not contain a “filter” as
 required by claim 9. Id. at 834. The court contrasted the
 openings in DZEM’s rubber cover, which the court de-
 scribed as “relatively large,” with the apertures disclosed
 in the ’038 patent, which the court described as “tiny.” See
 id. at 832, 834. The court also held that SSI had forfeited
 its argument that DZEM infringed claim 9 of the ’038 pa-
 tent under the doctrine of equivalents. Id. at 834.
                              C
     DZEM’s counterclaim for tortious interference is based
 on letters that SSI sent to several domestic and foreign
 companies advising them of SSI’s lawsuit against DZEM.
 Some of the letters added that SSI was seeking German
 patent protection for its sensors. DZEM alleges that the
 companies that SSI contacted were customers of DZEM.
     The district court granted summary judgment to SSI
 on the tortious interference counterclaim on the ground
 that “SSI’s communications with companies in countries
 where SSI enjoys patent protection were protected” under
 the Noerr-Pennington doctrine, which “prohibits suits
 based on a defendant’s petition to the government for re-
 dress of grievances.” SSI, 559 F. Supp. 3d at 835–37. With
 respect to SSI’s alleged communications with companies in
 other countries, the court granted summary judgment in
 favor of SSI because DZEM did not “adduce evidence that
 it had prospective contracts with those companies.” Id. at
 837.
     In light of its decision to grant summary judgment of
 non-infringement of the ’153 and ’038 patents, the district
 court also dismissed without prejudice DZEM’s counter-
 claims for invalidity of those patents. The court explained
 that “[n]othing in DZEM’s complaint or any of the parties’
 briefing suggests that DZEM faces any risk of future pros-
 ecution under either of the patents-in-suit, so there is no
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 need for the court to determine whether the patents are
 invalid.” Id. at 835. This appeal followed.
                                II
                                A
     SSI argues that the district court erred in construing
 claim 1 of the ’153 patent to require that the contaminant
 determination take into account the measured volume of
 the fluid. In so construing the claim, the district court re-
 lied on the prosecution history of the ’153 patent. In par-
 ticular, the court observed that the inventors amended
 claim 1 during prosecution to incorporate the error-detec-
 tion capability described in the specification. SSI, 559 F.
 Supp. 3d at 829–30. We discern no error in the district
 court’s analysis.
      The specification of the ’153 patent discloses two types
 of errors that the system may detect: (1) whether the meas-
 ured volume exceeds the maximum volume of the tank; and
 (2) whether the system detects the DEF being diluted at
 the same time that the level of the fluid is decreasing. ’153
 patent, col. 11, ll. 35–42; id. at col. 12, ll. 38–60. Those two
 potential errors correspond closely to the two alternative
 limitations added to amended claim 1, which are “a)
 whether a measured volume is out of range and b) a dilu-
 tion of the fluid is detected while the measured volume of
 the fluid decreases.” See J.A. 1093. Those two potential
 errors also appear in dependent claims 30 and 31, respec-
 tively, although the patent uses slightly different language
 in those claims. Nonetheless, in view of the parallelism be-
 tween the amendment to claim 1 and the error-detection
 capabilities disclosed elsewhere in the ’153 patent, we
 agree with the district court that the amendment to claim
 1 was intended to capture the error-detection capability of
 the controller.
    To determine whether one of the two errors described
 above has occurred, the controller must necessarily com-
 pare its measured volume either to the actual capacity of
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 10                              SSI TECHNOLOGIES, LLC v.
          DONGGUAN ZHENGYANG ELECTRONIC MECHANICAL LTD.

 the tank or to a previous volume measurement. That fact
 strongly supports the district court’s construction of the
 claim, which requires the contamination determination to
 be based in part on whether an error has occurred—a de-
 termination that is itself based on the measured volume of
 the fluid.
     The district court’s construction is further supported by
 the use of the phrase “measured volume” in claim 1. SSI’s
 position is that the “dilution” limitation of claim 1 is satis-
 fied so long as the volume of the liquid in the tank is de-
 creasing, which is true any time the engine of the vehicle
 is running. See J.A. 208. However, if that were true, the
 word “measured” would be superfluous, as the word “vol-
 ume” alone would be sufficient to give the claim the scope
 that DZEM proposes. The use of the term “measured vol-
 ume” therefore indicates that claim 1 requires that the vol-
 ume of the liquid in the tank must be determined and
 considered as part of the contamination analysis recited in
 claim 1. See Merck & Co. v. Teva Pharms. USA, Inc., 395
 F.3d 1364, 1372 (Fed. Cir. 2005) (“A claim construction that
 gives meaning to all the terms of the claim is preferred over
 one that does not do so.”).
      Having discerned no error in the district court’s con-
 struction of claim 1, we agree with the district court that
 there is no genuine dispute of material fact regarding in-
 fringement of that claim. SSI has pointed to evidence that
 DZEM’s accused sensors are capable of measuring the vol-
 ume of the fluid in the tank. See, e.g., J.A. 208, 787. How-
 ever, SSI has offered no evidence that DZEM’s accused
 sensors base their contaminant determinations on that vol-
 ume measurement. Because the claim requires the control-
 ler to be “configured to consider whether the fluid volume
 is decreasing in making the contamination determination,”
 see SSI, 559 F. Supp. 3d at 829, SSI’s evidence is insuffi-
 cient to create a triable issue regarding infringement. We
 therefore affirm the district court’s grant of summary judg-
 ment of non-infringement of the ’153 patent.
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 DONGGUAN ZHENGYANG ELECTRONIC MECHANICAL LTD.

                               B
     SSI next argues that the district court erred in grant-
 ing summary judgment of non-infringement of the ’038 pa-
 tent because the court applied an impermissibly narrow
 construction of the term “filter.” SSI also argues that the
 district court erred in concluding that SSI forfeited its
 claim of infringement under the doctrine of equivalents.
 We agree with SSI on both points.
                               1
     Adopting DZEM’s proposed construction of “filter,” the
 district court construed that term to mean “a porous struc-
 ture defining openings[] and configured to remove impuri-
 ties larger than said openings from a liquid or gas passing
 through the structure.” SSI, 559 F. Supp. 3d at 831–32.
 SSI proposed to the district court and maintains here that
 the term “filter” should be construed to mean “a device con-
 taining openings through which liquid is passed that blocks
 and separates out matter, such as air bubbles.” Appellant’s
 Br. 19. On their face, those constructions do not appear to
 differ significantly. However, the district court’s applica-
 tion of DZEM’s construction makes clear that there is a
 substantial difference between the two constructions.
      In explaining its construction, the district court stated
 that DZEM’s construction was persuasive in part because
 the discussion in the specification regarding filters indi-
 cated that “the effective aperture size is tiny—100 mi-
 crons.” SSI, 559 F. Supp. 3d at 832; see also ’038 patent,
 col. 5, ll. 13–17 (“It has been found through empirical test-
 ing . . . that an aperture size of 100 microns reduces the
 quantity of gas bubbles within a sensing area sufficiently
 enough to enable continuous measurements . . . .”). The
 court held that DZEM’s filters, by contrast, are not covered
 by claim 9 because the four openings in those filters are
 “relatively large.” SSI, 559 F. Supp. 3d at 834. According
 to the court, DZEM’s accused sensor “deflects larger bub-
 bles, and . . . admits fluid with smaller bubbles into the
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            DONGGUAN ZHENGYANG ELECTRONIC MECHANICAL LTD.

 sensing area through four openings and then ventilates the
 smaller bubbles from four side slits.” Id. As a result, the
 court stated, DZEM’s sensor “does not have a filter that ex-
 cludes bubbles by straining fluid through a porous surface.”
 Id. It is clear from that analysis that the district court un-
 derstood the word “porous” to require that the filter open-
 ings be smaller than a certain unspecified maximum size.
     The specification of the ’038 patent, however, contains
 no requirement regarding the size of the filter openings.
 Although it is true that each embodiment disclosed in the
 ’038 patent contains a mesh filter, which has very small
 openings, the scope of a claim is not ordinarily limited to
 preferred embodiments or specific examples in the specifi-
 cation. See Teleflex, Inc. v. Ficosa N. Am. Corp., 299 F.3d
 1313, 1328 (Fed. Cir. 2002). And while the specific embod-
 iments of the filters disclosed in the ’038 patent specifica-
 tion contain small holes, the general references to a “filter”
 in the specification are quite broad and do not reflect an
 intent to limit the term “filter” to the disclosed embodi-
 ments:
      •   “The filter blocks, or inhibits, air bubbles from
          entering a sensing area of the fluid sensor.” ’038
          patent, col. 2, ll. 6–7.
      •   “FIG. 5 illustrates a filter, or filter shroud, 250
          for prohibiting, or inhibiting, the flow of gas, such
          as but not limited to, gas bubbles (i.e., gas
          trapped in a liquid). In some embodiments, the
          filter 250 includes mesh, or one or more, mesh
          screens, 255 and a frame 260.” Id. at col. 4, ll.
          49–53 (emphasis added).
      •   “Thus, the invention provides, among other
          things, a sensor system including a filter for pre-
          venting gas bubbles from entering the sensor sys-
          tem.” Id. at col. 6, ll. 7–9.
     In view of those statements in the specification, we do
 not construe the term “filter” to require openings that are
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 smaller than a particular size. Rather, a filter need only
 perform the function set forth in claim 9 of the patent: to
 “substantially prohibit one or more gas bubbles of the fluid
 from entering the sensing area.”
      Like the claim language, the specification makes clear
 that the filter of the ’038 patent is not required to screen
 all bubbles from the sensing area of the sensor system, but
 only to “reduce[] the quantity of gas bubbles within a sens-
 ing area sufficiently enough to enable continuous measure-
 ments” by the sensors. ’038 patent, col. 5, ll. 14–17. Gas
 bubbles that “have a diameter smaller than the aperture
 size of the mesh screens” will pass through the filter. Id.
 at col. 5, ll. 10–12. In other words, as long as the openings
 in the filter are small enough to prevent at least some gas
 bubbles from entering the sensing area, the openings need
 not be smaller than any particular maximum size.
      Because the construction adopted by the district court
 could give rise to further disputes regarding the meaning
 of the word “porous”—a term that does not appear in the
 ’038 patent—we adopt SSI’s construction of the term “fil-
 ter.” That is, we hold that the term “filter” is properly con-
 strued to mean “a device containing openings through
 which liquid is passed that blocks and separates out mat-
 ter, such as air bubbles.” In light of our disposition of that
 issue, we vacate the district court’s grant of summary judg-
 ment with respect to the ’038 patent in its entirety, and
 remand for further proceedings consistent with this opin-
 ion.
                               2
      In granting summary judgment of non-infringement of
 the ’038 patent, the district court concluded that SSI had
 failed to develop its argument that DZEM’s accused sen-
 sors infringed under the doctrine of equivalents and there-
 fore had forfeited it. Id. The district court added that SSI’s
 equivalents argument also failed on the merits because “no
 reasonable jury could find that [the] DZEM sensor’s way of
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 achieving the function [excluding gas particles] is substan-
 tially the same as that claimed in the ’038 patent.” Id.
     We disagree with the district court’s conclusion that
 SSI forfeited its doctrine-of-equivalents infringement the-
 ory. SSI’s summary judgment brief contained a two-page
 argument on the doctrine of equivalents, to which DZEM
 responded in its reply brief. J.A. 1167–69 (SSI brief); SSI
 Techs., LLC v. Dongguan Zhengyang Elec. Mech. LTD, No.
 20-cv-19, Dkt. No. 130 at 33–34 (W.D. Wis. May 27, 2021)
 (DZEM reply). The discussion in SSI’s brief cited a portion
 of SSI’s expert’s report, which set forth the function, way,
 and result of the operation of DZEM’s accused products.
 J.A. 1168. SSI contended that the expert’s analysis estab-
 lished the basis for SSI’s claim of equivalence. Id. SSI’s
 discussion of the doctrine of equivalents in its briefing and
 its evidence in support of that discussion, although rela-
 tively limited, was sufficient to preserve that theory of in-
 fringement. Accordingly, SSI will not be precluded from
 arguing on remand that DZEM’s accused sensors infringe
 under the doctrine of equivalents.
                              C
     DZEM argues that the district court erred in granting
 summary judgment in favor of SSI on DZEM’s tortious in-
 terference counterclaim. Specifically, DZEM argues that
 SSI’s communications with DZEM’s customers are not pro-
 tected under the Noerr-Pennington doctrine. Even if the
 Noerr-Pennington doctrine is applicable, DZEM argues, the
 “sham litigation” exception to that doctrine applies to this
 case and renders SSI’s communications actionable.
     When a plaintiff brings a state-law tort claim that
 arises out of “a patentholder's good faith conduct in com-
 munications asserting infringement of its patent and warn-
 ing about potential litigation,” we have held that “federal
 patent law preempts state-law tort liability.” Globetrotter
 Software, Inc. v. Elan Comput. Grp., Inc., 362 F.3d 1367,
 1374 (Fed. Cir. 2004). In Globetrotter, we adopted the
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 standard of objective baselessness from Noerr as part of the
 test for determining whether pre-litigation communica-
 tions regarding patent infringement are unprotected. See
 id. at 1375–77 (citing E. R. R. Presidents Conf. v. Noerr Mo-
 tor Freight, Inc., 365 U.S. 127 (1961), and Pro. Real Est.
 Invs., Inc. v. Columbia Pictures Indus., Inc., 508 U.S. 49
 (1993)). Thus, in order to assert a claim “that a patent
 holder has engaged in wrongful conduct by asserting
 claims of patent infringement,” the plaintiff “must estab-
 lish that the claims of infringement were objectively base-
 less.” Id. at 1377. Objective baselessness must be
 established before the court may consider the subjective
 motivations of the patentee. See id. at 1375–76 & n.8; GP
 Indus., Inc. v. Eran Indus., Inc., 500 F.3d 1369, 1375 (Fed.
 Cir. 2007).
     The district court held that SSI’s infringement claims
 were not objectively baseless, and we discern no error in
 that conclusion. In particular, the district court pointed to
 SSI’s expert report regarding infringement as evidence
 that the suit was not objectively baseless. SSI, 559 F.
 Supp. 3d at 836. We have held that the existence of an
 expert opinion can be evidence that a party’s position is not
 unreasonable, even if there is conflicting expert testimony
 in the record. 800 Adept, Inc. v. Murex Sec., Ltd., 539 F.3d
 1354, 1371 (Fed. Cir. 2008). DZEM was required to estab-
 lish by clear and convincing evidence that SSI’s infringe-
 ment suit was objectively baseless, but it failed to introduce
 any evidence of objective baselessness. See Dominant Sem-
 iconductors Sdn. Bhd. v. OSRAM GmbH, 524 F.3d 1254,
 1263–64 (Fed. Cir. 2008). In view of SSI’s expert report
 and DZEM’s failure to adduce evidence of objective base-
 lessness, the district court properly granted summary judg-
 ment that SSI’s communications to outside parties,
 including those DZEM claimed to be its customers or pro-
 spective customers, were protected.
    DZEM separately argues that SSI’s communications to
 DZEM’s foreign customers are not protected because “SSI
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 16                              SSI TECHNOLOGIES, LLC v.
          DONGGUAN ZHENGYANG ELECTRONIC MECHANICAL LTD.

 could not obtain [government] action where it has no rights
 to do so [i.e., no patent protection].” Cross-Appellant’s Br.
 55. We disagree that those communications were not pro-
 tected. Each letter sent by SSI, on its face, refers only to
 alleged infringement of a United States patent. See, e.g.,
 J.A. 2102–03, 2111–13. Foreign entities can infringe a
 United States patent if they make, use, or sell an infringing
 product in the United States, or import an infringing prod-
 uct into the United States. See 35 U.S.C. § 271(a). The
 argument that SSI could not obtain government action
 against the foreign entities to which it sent letters is there-
 fore unpersuasive.
     Accordingly, we affirm the district court’s grant of sum-
 mary judgment to SSI on the tortious interference counter-
 claim.
                               D
     DZEM also argues that the district court erred in dis-
 missing DZEM’s invalidity counterclaims without preju-
 dice in light of the court’s grant of summary judgment of
 non-infringement. We review a district court’s decision to
 dismiss an invalidity counterclaim without prejudice for an
 abuse of discretion. Flexuspine, Inc. v. Globus Med., Inc.,
 879 F.3d 1369, 1375–76 (Fed. Cir. 2018).
      A district court lacks jurisdiction over a declaratory
 judgment counterclaim if that claim does not present a jus-
 ticiable case or controversy under Article III of the Consti-
 tution. MedImmune, Inc. v. Genentech, Inc., 549 U.S. 118,
 126–27 (2007). In general, a determination of non-infringe-
 ment does not moot a counterclaim of invalidity such that
 there is no Article III case or controversy. Fort James Corp.
 v. Solo Cup Co., 412 F.3d 1340, 1348–49 (Fed. Cir. 2005);
 Korszun v. Pub. Techs. Multimedia, Inc., 96 F. App’x 699,
 700 (Fed. Cir. 2004); see generally Cardinal Chem. Co. v.
 Morton Int’l, Inc., 508 U.S. 83 (1993). Moreover, once the
 case-or-controversy requirement has been satisfied, juris-
 diction continues “absent further information.” Benitec
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 SSI TECHNOLOGIES, LLC v.                                   17
 DONGGUAN ZHENGYANG ELECTRONIC MECHANICAL LTD.

 Australia, Ltd. v. Nucleonics, Inc., 495 F.3d 1340, 1344–45
 (Fed. Cir. 2007) (emphasis omitted). DZEM’s invalidity
 counterclaims therefore likely satisfied the case-or-contro-
 versy requirement even after the district court granted
 summary judgment of non-infringement.
     However, even in cases in which a district court has ju-
 risdiction to hear a declaratory judgment claim, the Declar-
 atory Judgment Act permits the court to decline to exercise
 jurisdiction over the claim as a matter of discretion. Wilton
 v. Seven Falls Co., 515 U.S. 277, 286–87 (1995). Consistent
 with that principle, we have repeatedly held that a district
 court “faced with an invalidity counterclaim challenging a
 patent that it concludes was not infringed may either hear
 the claim or dismiss it without prejudice.” Liquid Dynam-
 ics Corp. v. Vaughan Co., 355 F.3d 1361, 1371 (Fed. Cir.
 2004); Flexuspine, 879 F.3d at 1376; Phonometrics, Inc. v.
 N. Telecom Inc., 133 F.3d 1459, 1468 (Fed. Cir. 1998); Nys-
 trom v. TREX Co., 339 F.3d 1347, 1351 & n.* (Fed. Cir.
 2003); Benitec, 495 F.3d at 1353 & n.4 (Dyk, J., dissenting);
 AstraZeneca LP v. Breath Ltd., 542 F. App’x 971, 981–82
 (Fed. Cir. 2013), as amended (Dec. 12, 2013).
     In this case, the district court dismissed the invalidity
 counterclaims without prejudice because “[n]othing in
 DZEM’s complaint or any of the parties’ briefing suggests
 that DZEM faces any risk of future prosecution under ei-
 ther of the patents-in-suit, so there is no need for the court
 to determine whether the patents are invalid.” SSI, F.
 Supp. 3d at 834–35. We discern no abuse of discretion in
 the district court’s decision to dismiss the counterclaims on
 that basis. See AstraZeneca, 542 F. App’x at 982 (affirming
 dismissal of invalidity counterclaim in light of the district
 court’s observation that “the non-infringement judgment
 firmly and clearly resolves the case, and [the defendant]
 has not shown how a judgment of invalidity would provide
 any additional benefit” (citation omitted)).
    Because we vacate the district court’s summary judg-
 ment decision with respect to the ’038 patent, we also
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 18                              SSI TECHNOLOGIES, LLC v.
          DONGGUAN ZHENGYANG ELECTRONIC MECHANICAL LTD.

 vacate the dismissal of the invalidity counterclaim regard-
 ing the ’038 patent. As to the ’153 patent, however, the
 district court permissibly exercised its discretion in dis-
 missing the invalidity counterclaims in light of the absence
 of any apparent risk of future actions against DZEM. We
 therefore affirm the dismissal of the invalidity counter-
 claim regarding the ’153 patent.
                            ***
     In summary, we reverse the district court’s construc-
 tion of the term “filter” as used in the claims of the ’038
 patent and vacate the district court’s grant of summary
 judgment with respect to the ’038 patent. We affirm the
 district court’s grant of summary judgment with respect to
 the ’153 patent and DZEM’s counterclaim for tortious in-
 terference. We vacate the dismissal of the invalidity coun-
 terclaim regarding the ’038 patent but affirm the dismissal
 of the invalidity counterclaim regarding the ’153 patent.
      No costs.
      AFFIRMED-IN-PART, REVERSED-IN-PART,
        VACATED-IN-PART, AND REMANDED