  United States Court of Appeals
      for the Federal Circuit
                ______________________

    TINNUS ENTERPRISES, LLC, ZURU LTD.,
              Plaintiffs-Appellees

                          v.

   TELEBRANDS CORPORATION, BED BATH &
              BEYOND, INC.,
            Defendants-Appellants
           ______________________

                      2016-1410
                ______________________

   Appeal from the United States District Court for the
Eastern District of Texas in No. 6:15-cv-00551-RWS-JDL,
Judge Robert Schroeder, III.
                 ______________________

              Decided: January 24, 2017
               ______________________

   THOMAS MANSFIELD DUNLAP, Dunlap Bennett &
Ludwig PLLC, Leesburg, VA, argued for plaintiffs-
appellees. Also represented by DAVID LUDWIG, ERIC
LORENZ OLAVSON, ROBERT D. SPENDLOVE; CORTLAND
CHRISTOPHER PUTBRESE, Richmond, VA.

    DAVID MICHAEL UNDERHILL, Boies, Schiller & Flexner,
LLP, Washington, DC, argued for defendant-appellant
Telebrands Corporation. Also represented by STACEY K.
GRIGSBY, AMY LYNN NEUHARDT; DAVID BOIES, Armonk,
NY; ELANA ARAJ, Cooper & Dunham, LLP, New York, NY.
2      TINNUS ENTERPRISES, LLC   v. TELEBRANDS CORPORATION




   ROBERT THOMAS MALDONADO, ELANA ARAJ, Cooper &
Dunham, LLP, New York, NY, appeared for defendant-
appellant Bed Bath & Beyond, Inc.
                ______________________

    Before MOORE, WALLACH, and STOLL, Circuit Judges.
STOLL, Circuit Judge.
    This is an appeal from the grant of a preliminary in-
junction. The United States District Court for the East-
ern District of Texas ruled for the patentee, Tinnus
Enterprises, LLC, and entered a preliminary injunction
barring Telebrands Corporation from selling its accused
product, Balloon Bonanza, or any colorable imitation
thereof. Telebrands alleges that the district court abused
its discretion by concluding that (1) the asserted claims
were likely infringed; (2) the claims were not vulnerable
on indefiniteness or obviousness grounds; and (3) Tinnus
made a showing of irreparable harm. For the reasons
stated below, we disagree with Telebrands and affirm the
district court’s grant of a preliminary injunction.
                        BACKGROUND
     Tinnus Enterprises, LLC produces a toy for filling wa-
ter balloons covered by U.S. Patent No. 9,051,066, which
it calls “Bunch O Balloons.” Telebrands Corporation sells
a competing product, “Balloon Bonanza.” Both products
attach to a hose and fill multiple water balloons at once
by channeling the water into the balloons through a set of
hollow tubes. A side-by-side comparison of the rival
products is shown below:
TINNUS ENTERPRISES, LLC   v. TELEBRANDS CORPORATION      3




Appellee Br. 11.
    Tinnus and ZURU Ltd. 1 (collectively, “Tinnus”) sued
Telebrands and Bed Bath & Beyond, Inc. (collectively,
“Telebrands”) for infringement of the ’066 patent and
subsequently moved for a preliminary injunction. The
Magistrate Judge issued a Report and Recommendation
(“R&R”) in which he recommended granting Tinnus’s
motion. Tinnus Enters., LLC v. Telebrands Corp., No. 15-
00551, 2015 WL 11089479 (E.D. Tex. Sept. 11, 2015)
(Magistrate Op.). The district court overruled Telebrands’
objections to the R&R, adopted the R&R’s findings, and
granted Tinnus’s motion. Tinnus Enters., LLC v. Tele-
brands Corp., No. 15-00551, 2015 WL 11089480 (E.D.
Tex. Dec. 2, 2015). Shortly thereafter, the Patent Trial
and Appeal Board instituted a Post-Grant Review pro-
ceeding for the ’066 patent, finding all claims were more
likely than not invalid based on the same arguments
considered by the district court.
                   I.   The ’066 Patent
   The ’066 patent relates to a system and method for
simultaneously filling multiple containers with fluid. ’066


   1   ZURU is the exclusive licensee of all present and
future patent rights owned by Tinnus that relate to the
Bunch O Balloons product.
4      TINNUS ENTERPRISES, LLC   v. TELEBRANDS CORPORATION



patent col. 1 ll. 19–21. One application of the ’066 patent
is the mass-filling of water balloons, as shown in the
embodiment depicted in Figure 1:




This embodiment includes a housing 12 with two ends:
end A is removably attached to a fluid source, e.g., hose
14, and end B is attached to a plurality of hollow tubes 16.
Id. col. 2 ll. 35–37. A plurality of containers 18—in this
instance, balloons—are clamped to the tubes 16 using
elastic valves 20, which can include elastic fasteners, such
as O-rings. Id. col. 2 ll. 51–59. The patent refers to the
force applied by the elastic valves to keep the containers
attached to the tubes as the “connecting force.” Id. col. 3
ll. 52–64. Once the fluid source is turned on, multiple
TINNUS ENTERPRISES, LLC   v. TELEBRANDS CORPORATION           5



balloons are filled simultaneously: fluid flows from hose
14, through the housing 12, and into the containers 18
through the tubes 16. Id. col. 3 ll. 41–42.
    The ’066 patent teaches three ways to overcome the
connecting force such that the containers detach from the
tubes. These include: (1) pulling the containers away
from the tubes, id. col. 3 ll. 48–51; (2) shaking the device
to overcome the connecting force holding the containers to
the tubes, id. col. 3 ll. 52–57; and (3) allowing the contain-
ers to fall off due to gravity, id. col. 3 ll. 65–67. After
being detached from the tubes using any of the above-
described methods, the elastic valve constricts and seals
the balloon. Id. col. 4 ll. 64–67.
    Independent claim 1 is illustrative, and it recites:

    1. An apparatus comprising:
        a housing comprising an opening at a first end,
    and a plurality of holes extending through a
    common face of the housing at a second end;
        a plurality of flexible hollow tubes, each hollow
    tube attached to the housing at a respective one of
    the holes at the second end of the housing;
        a plurality of containers, each container re-
    movably attached to a respective one of the hollow
    tubes; and
        a plurality of elastic fasteners, each elastic fas-
    tener clamping a respective one of the plurality of
    containers to a corresponding hollow tube, and
    each elastic fastener configured to provide a con-
    necting force that is not less than a weight of one
    of the containers when substantially filled with
    water, and to automatically seal its respective one
    of the plurality of containers upon detaching the
    container from its corresponding hollow tube, such
6      TINNUS ENTERPRISES, LLC   v. TELEBRANDS CORPORATION



    that shaking the hollow tubes in a state in which
    the containers are substantially filled with water
    overcomes the connecting force and causes the con-
    tainers to detach from the hollow tubes thereby
    causing the elastic fasteners to automatically seal
    the containers,
        wherein the apparatus is configured to fill the
    containers substantially simultaneously with a
    fluid.
Id. col. 6 ll. 30–53 (emphasis added to indicate disputed
limitations).
              II. District Court Proceedings
    Tinnus filed its patent infringement suit against Tel-
ebrands on the day the ’066 patent issued and filed a
motion for a preliminary injunction nine days later. The
Magistrate Judge reviewed the briefing and held a hear-
ing to evaluate evidence on the preliminary injunction
factors before recommending that Tinnus’s motion be
granted.
    In his infringement analysis, the Magistrate Judge
reviewed Tinnus’s claim chart, which mapped the claim
limitations onto the Balloon Bonanza product. The claim
chart explained why each limitation was met and includ-
ed photographs of the allegedly infringing product, images
from the product instruction manual, screenshots of the
product, and related product videos. Telebrands coun-
tered that its product did not infringe because its tubes
can slide in and out of the housing and therefore are not
“attached” to the housing, as required by the claims.
Relying on the plain and ordinary meaning of “at-
tached”—“connected or joined to something”—the Magis-
trate Judge concluded that the “tubes of the Balloon
Bonanza product are connected to the housing holes in
order for the product to function properly.” Magistrate
Op., 2015 WL 11089479, at *4. Telebrands also asserted
TINNUS ENTERPRISES, LLC   v. TELEBRANDS CORPORATION       7



that disputes over the meaning of “not less than” in
conjunction with the term “connecting force” meant that
the elastic fastener limitation was not met. 2 The Magis-
trate Judge, however, found that this argument was
actually premised on Telebrands’ contention that shaking
is not required to detach the balloons from the tubes in
the Balloon Bonanza product. Because the Balloon Bo-
nanza manual instructs the user to “[t]urn off water and
give balloons a shake to release,” id. (alteration in origi-
nal) (quoting J.A. 447), the Magistrate Judge concluded
that Balloon Bonanza likely met the disputed limitation,
regardless of how it construed “connecting force” or “not
less than.”
    The Magistrate Judge also found that Telebrands’ in-
definiteness and enablement arguments failed to raise a
substantial question of validity. First, Telebrands con-
tended that the term “substantially filled” was indefinite
because it required subjectivity in determining when the
container had become substantially filled. The Magis-
trate Judge disagreed, noting that there is no per se rule
that the term “substantially” is indefinite. The Magis-
trate Judge further identified “specific parameters” in the
claims describing how to determine whether a container is
substantially filled—for example, “when the ‘water over-
comes the connecting force and causes the containers to
detach from the hollow tubes.’” Id. at *5 (quoting ’066
patent col. 6 ll. 48–52). Second, Telebrands alleged that
the term “connecting force” was not enabled because the
’066 patent never describes the type of force where the
connecting force is not less than the weight of the con-



   2    This limitation requires “each elastic fastener con-
figured to provide a connecting force that is not less than
a weight of one of the containers when substantially filled
with water.” Magistrate Op., 2015 WL 11089479, at *4
(quoting ’066 patent col. 6 ll. 41–44).
8       TINNUS ENTERPRISES, LLC   v. TELEBRANDS CORPORATION



tainer, i.e., when the container will not detach from the
tube. The Magistrate Judge disagreed because claim 1
itself recites a shaking limitation for detaching the con-
tainers when the connecting force is not less than the
weight of the containers when substantially filled with
water, which was consistent with the teachings in the
specification.
    Next, Telebrands argued that claim 1 was obvious
over U.S. Patent No. 5,826,803 (“Cooper”) in view of U.S.
Patent Publication No. 2013/0118640 (“Saggio”), as well
as Cooper in view of Saggio and U.S. Patent Publication
No. 2005/0004430 (“Lee”). 3 Cooper discloses a garden
sprinkler, as shown in Figure 4 below, that attaches to a
garden hose and has multiple bendable tubes 18. ’803
patent col. 2 ll. 22–28, col. 3 ll. 19–23.




Saggio teaches a system, shown in Figure 7 below, that
fills multiple tie-less water balloons simultaneously using
a one-way valve, as depicted in Figure 5 reproduced


    3    Telebrands offered additional obviousness combi-
nations based on other references at the district court
level, but it does not raise them on appeal.
TINNUS ENTERPRISES, LLC   v. TELEBRANDS CORPORATION      9



below. When water flows into the balloon through chan-
nel 20, the water pressure pushes seal 16 and inner
membrane 18 up against the outer wall of the balloon 12,
thereby locking in the water and preventing it from
escaping. J.A. 741.




Lee discloses a method and apparatus for endoscopically
inserting a balloon into a person’s stomach to treat obesi-
ty. J.A. 753. As shown in Figure 6, a balloon is attached
to the inner guide pipe 3 using a rubber band 2 with a
high elastic force that stably binds the balloon to the
inner guide pipe when it is expanded. J.A. 754. The
outer guide pipe 4 can slide forward towards the balloon
once the endoscope and balloon are properly placed inside
the stomach, which pushes the rubber band off of inner
guide pipe 3 and seals the balloon. Id.
10     TINNUS ENTERPRISES, LLC   v. TELEBRANDS CORPORATION



    The Magistrate Judge found the combination of
Cooper and Saggio deficient because neither reference
disclosed the required “elastic fasteners.” The combina-
tion of Cooper and Saggio with Lee fared no better be-
cause the Magistrate Judge found no evidence that Lee’s
rubber band would provide the claimed connecting force.
Moreover, the Magistrate Judge was not convinced that a
person of ordinary skill in the art (“POSA”) would have
been motivated to combine Lee with Cooper and Saggio
because the references come from diverse fields: endoscop-
ic balloon insertion devices for obesity treatment, garden
sprinklers, and water balloon filling systems, respectively.
Finally, even if Telebrands were able to establish a prima
facie case of obviousness, the Magistrate Judge noted that
secondary considerations, such as commercial success and
copying, would be relevant because the Balloon Bonanza
product appeared to be “a near identical replica” of the
patented Bunch O Balloons product. Magistrate Op.,
2015 WL 11089479, at *7.
     With respect to irreparable harm, the Magistrate
Judge found evidence of price erosion, consumer confu-
sion, reputational harm, and loss of goodwill based on
customer calls, emails, and online reviews. As evidence of
price erosion, the Magistrate Judge explained that, while
ZURU initially sold Bunch O Balloons for $17 in August
2014, in response to direct competition from Balloon
Bonanza, ZURU reduced the price of Bunch O Balloons to
$12.99, and eventually to $9.99 by mid-2015. According
to the Magistrate Judge, the “market entry and continual-
ly reduced sale prices of Telebrands’ allegedly infringing
product has driven down the price at which the Bunch O
Balloons product has sold,” leading to the “harm that is
ultimately irreparable here” in the form of the “now
lowered price of sale for the present monopoly right.” Id.
at *8 (citing Douglas Dynamics, LLC v. Buyers Prods. Co.,
717 F.3d 1336, 1345 (Fed. Cir. 2013) (“Where two compa-
nies are in competition against one another, the patentee
TINNUS ENTERPRISES, LLC   v. TELEBRANDS CORPORATION     11



suffers the harm—often irreparable—of being forced to
compete against products that incorporate and infringe its
own patented inventions.”)).
    To establish consumer confusion, reputational harm,
and loss of good will, Tinnus provided evidence of conver-
sations and reviews from confused customers. For exam-
ple, the Magistrate Judge cited evidence that one
customer called ZURU to inquire about her product order
when, in fact, the customer had purchased Balloon Bo-
nanza instead and that another customer left a review
online stating “the inventor of the Balloon Bonanza who
invented this product was formerly called Bunch O Bal-
loons.” Id. Customers also sent emails to Tinnus asking
whether Balloon Bonanza was invented by Mr. Malone,
Tinnus’s founder, and wondering whether he had licensed
his invention to Telebrands. This evidence convinced the
Magistrate Judge that consumers were confused about
which product is sold by which company and that the
patented Bunch O Balloons product had “been diluted in
the minds of the consuming public.” Id. Aside from the
consumer confusion, the false association between the
products harmed Tinnus because Bunch O Balloons
received better ratings than Balloon Bonanza on Ama-
zon.com and ToysRUs.com. Even though most of these
examples pre-dated the issuance of the ’066 patent, the
Magistrate Judge found that several of the harms, includ-
ing customer confusion, were ongoing.
    The Magistrate Judge also concluded that the balance
of hardships and public interest factors weighed in Tin-
nus’s favor due to the relative size of the parties and the
strong public interest in enforcing valid patents. Because
Tinnus established all four factors required for a prelimi-
nary injunction, the Magistrate Judge recommended
granting Tinnus’s motion.
    Telebrands timely filed its objections to the Magis-
trate Judge’s R&R, alleging that it erred (1) by failing to
12       TINNUS ENTERPRISES, LLC   v. TELEBRANDS CORPORATION



provide a claim construction for the “attached,” “connect-
ing force,” “elastic fastener,” and “shaking” limitations; (2)
by improperly shifting the burden of proof to Telebrands
on infringement and invalidity; and (3) by relying on
insufficient evidence to support findings of commercial
success and copying. 4 Notably, Telebrands did not object
to the Magistrate Judge’s indefiniteness ruling or its
rejection of Telebrands’ obviousness arguments. The
district court overruled each of the objections, adopted the
R&R’s findings, and entered a preliminary injunction.
                   III. PTAB Proceedings
     Operating in parallel to the district court proceeding
was Telebrands’ PGR petition seeking to invalidate the
’066 patent. The PTAB, relying on the same evidence and
arguments before the district court, instituted review on
all claims of the ’066 patent shortly after the district court
granted Tinnus’s request for a preliminary injunction. 5
    The PTAB found that claim 1’s “shake-to-detach” fea-
ture 6 was likely indefinite because the specification and



     4  Telebrands also objected to the R&R’s findings
with respect to irreparable harm, but this portion of its
objections was not included in the appellate record. See
Defendants’ Objections to the Report and Recommenda-
tion Regarding Plaintiffs’ Motion for Preliminary Injunc-
tion (Dkt. No. 9) at 4–5, Tinnus Enters., LLC v.
Telebrands Corp., No. 15-00551 (E.D. Tex. Sept. 25, 2015),
ECF No. 70.
    5   The PTAB instituted review for claims 1–6, 8, and
10–14. Tinnus disclaimed claims 7 and 9. Telebrands
Corp. v. Tinnus Enters., LLC, PGR2015-18, 2016 WL
270152, at *1 n.1 (PTAB Jan. 4, 2016) (Institution Deci-
sion).
    6   The PTAB defined the following italicized claim
language as the shake-to-detach feature: “each elastic
TINNUS ENTERPRISES, LLC   v. TELEBRANDS CORPORATION         13



prior art both fail to provide “any objective standard for
measuring the scope of ‘filled’ or ‘substantially filled,’” and
the specification sets forth no limit on the amount of
shaking needed to detach a filled container from the tube.
Institution Decision, 2016 WL 270152, at *7–8. 7 The
PTAB also found that a combination of Cooper, Saggio,
and Lee would likely render claim 1 obvious. Id. at *14.
According to the PTAB, a POSA would have combined
Saggio with Cooper to create a multi-balloon filling as-
sembly by “attach[ing] balloons to the ends of the flexible
tubes of Cooper’s sprinkler” and would have added Lee’s
mechanism for clamping and sealing the balloons once
filled because it was “reasonably pertinent to a particular
problem the inventor of the ’066 patent was trying to
solve.” Id. at *13.
    Telebrands appeals the preliminary injunction en-
tered by the district court. We have jurisdiction pursuant
to 28 U.S.C. § 1292(a)(1) and (c)(1).



fastener configured to provide a connecting force that is
not less than a weight of one of the containers when
substantially filled with water, . . . such that shaking the
hollow tubes in a state in which the containers are sub-
stantially filled with water overcomes the connecting force
and causes the containers to detach from the hollow
tubes.” Id. at *7 (alteration in original).
    7   We are aware that the PTAB issued a Final Writ-
ten Decision on December 30, 2016, concluding that the
claims of the ’066 patent are indefinite. The PTAB’s
decision is not binding on this court, and based on the
record before us and the applicable standard of review, it
does not persuade us that the district court abused its
discretion in granting the preliminary injunction. The
parties are, of course, free to ask the district court to
reconsider its preliminary injunction in light of the
PTAB’s Decision.
14     TINNUS ENTERPRISES, LLC   v. TELEBRANDS CORPORATION



                       DISCUSSION
   On appeal, Telebrands challenges the district court’s
conclusions on likelihood of success on the merits—
including its findings on infringement and invalidity—as
well as its conclusions on irreparable harm, which we
address in turn.
    “A decision to grant or deny a preliminary injunction is
within the sound discretion of the district court, based
upon its assessment of four factors: (1) the likelihood of
the patentee’s success on the merits; (2) irreparable harm
if the injunction is not granted; (3) the balance of hard-
ships between the parties; and (4) the public interest.”
Procter & Gamble Co. v. Kraft Foods Glob., Inc., 549 F.3d
842, 847 (Fed. Cir. 2008) (quoting Oakley, Inc. v. Sunglass
Hut Int’l, 316 F.3d 1331, 1338–39 (Fed. Cir. 2003)). With
respect to establishing a likelihood of success on the
merits, “the patentee seeking a preliminary injunction in
a patent infringement suit must show that it will likely
prove infringement, and that it will likely withstand
challenges, if any, to the validity of the patent.” Titan
Tire Corp. v. Case New Holland, Inc., 566 F.3d 1372, 1376
(Fed. Cir. 2009). An accused infringer “can defeat a
showing of likelihood of success on the merits by demon-
strating a substantial question of validity or infringe-
ment.” Trebro Mfg., Inc. v. Firefly Equip., LLC, 748 F.3d
1159, 1165 (Fed. Cir. 2014) (citing Aria Diagnostics, Inc.
v. Sequenom, Inc., 726 F.3d 1296, 1304 (Fed. Cir. 2013)).
     In general, we review preliminary injunctions using
the law of the regional circuit—here, the Fifth Circuit—
because “[t]he grant, denial, or modification of a prelimi-
nary injunction . . . is not unique to patent law.” Id.
(alteration in original) (quoting Aevoe Corp. v. AE Tech
Co., 727 F.3d 1375, 1381 (Fed. Cir. 2013)). “However, the
Federal Circuit has itself built a body of precedent apply-
ing the general preliminary injunction considerations to a
large number of factually variant patent cases, and gives
TINNUS ENTERPRISES, LLC   v. TELEBRANDS CORPORATION       15



dominant effect to Federal Circuit precedent insofar as it
reflects considerations specific to patent issues.” Murata
Mach. USA v. Daifuku Co., 830 F.3d 1357, 1363 (Fed. Cir.
2016) (quoting Trebro, 748 F.3d at 1165). Both the Fifth
Circuit and the Federal Circuit review preliminary in-
junctions for an abuse of discretion. See Sepulvado v.
Jindal, 729 F.3d 413, 417 (5th Cir. 2013); see also Procter
& Gamble, 549 F.3d at 845. A party can establish an
abuse of discretion in the preliminary injunction context
“by showing that the court made a clear error of judgment
in weighing relevant factors or exercised its discretion
based upon an error of law or clearly erroneous factual
findings.” Abbott Labs. v. Andrx Pharm., Inc., 452 F.3d
1331, 1335 (Fed. Cir. 2006) (quoting Polymer Techs., Inc.
v. Bridwell, 103 F.3d 970, 973 (Fed. Cir. 1996)).
     Under Fifth Circuit law, where a party fails to object
to a magistrate judge’s findings of fact, conclusions of law,
or recommendation to the district court, plain error re-
view applies to those unobjected-to factual findings and
legal conclusions adopted by the district court. Douglass
v. United Servs. Auto. Ass’n, 79 F.3d 1415, 1430 (5th Cir.
1996) (en banc), superseded by statute on other grounds,
28 U.S.C. § 636(b)(1) (extending time to file objections
from ten to fourteen days). “To prevail under [the plain
error] standard, the appellant ‘must show (1) that an
error occurred; (2) that the error was plain, which means
clear or obvious; (3) the plain error must affect substan-
tial rights; and (4) not correcting the error would seriously
impact the fairness, integrity, or public reputation of
judicial proceedings.’” Ortiz v. City of San Antonio Fire
Dep’t, 806 F.3d 822, 825–26 (5th Cir. 2015) (quoting
Septimus v. Univ. of Hous., 399 F.3d 601, 607 (5th Cir.
2005)). “When the nature of the claimed error is a ques-
tion of fact, however, the possibility that such a finding
could rise to the level of obvious error required to meet
part of the standard for plain error is remote.” Casas v.
Aduddell, 404 F. App’x 879, 881 (5th Cir. 2010).
16     TINNUS ENTERPRISES, LLC   v. TELEBRANDS CORPORATION



                 I.   Patent Infringement
     On appeal, Telebrands first faults the district court
for failing to construe the terms “not less than” and “con-
necting force.” Telebrands also alleges clear error in the
district court’s conclusions that the Balloon Bonanza
tubes are “attached” to the housing and meet the shake to
detach limitation. For the reasons explained below, none
of these arguments are persuasive.
    An infringement analysis involves the two-step pro-
cess of “construing the claims and comparing the properly
construed claims to the accused product.” Advanced Steel
Recovery, LLC v. X-Body Equip., Inc., 808 F.3d 1313, 1316
(Fed. Cir. 2015). Infringement is a question of fact, which
we review on appeal for clear error. See AstraZeneca LP
v. Apotex, Inc., 633 F.3d 1042, 1056 (Fed. Cir. 2010).
     Contrary to Telebrands’ argument, the R&R, which
was adopted by the district court, did not refuse to con-
strue the terms “not less than” and “connecting force.”
Instead, the R&R acknowledged Telebrands’ disagree-
ment regarding those terms but concluded that Tinnus
was likely to succeed on its infringement claim “irrespec-
tive of the interpretation of these claim terms.” Magis-
trate Op., 2015 WL 11089479, at *4. The R&R reached
this conclusion because it found that Telebrands’ claim
construction argument hinged on the contention that
shaking is not required to detach the balloons from the
tubes. Because the Balloon Bonanza instruction manual
tells users to “[t]urn off water and give balloons a shake to
release,” id. (alteration in original), the Magistrate Judge
determined that Telebrands’ position conflicted with the
record evidence and failed to demonstrate that Tinnus
was unlikely to succeed on its infringement claim. It was
not clear error for the district court to adopt this finding.
    Next, Telebrands challenges the district court’s appli-
cation of the claim term “attached” to the Balloon Bonan-
za product because its tubes allegedly “do not connect or
TINNUS ENTERPRISES, LLC   v. TELEBRANDS CORPORATION       17



join to the housing, but rather slide in and out of the holes
in the common face of the housing.” Appellant Br. 24–25.
The R&R applied the plain and ordinary meaning for the
term “attached,” i.e., “connected or joined to something,”
and found that the Balloon Bonanza product’s tubes must
be “connected to” the housing’s holes in order for it to
function properly. Magistrate Op., 2015 WL 11089479, at
*4         (citing      Merriam-Webster          Dictionary,
https://www.merriam-webster.com/dictionary/attached
(last visited Dec. 19, 2016)). This must be so, according to
the R&R, because the housing accepts water from the
hose at one end and sends the water through the holes at
the other end, which are connected to hollow tubes for
filling the balloons. The R&R’s analysis of the “attached”
limitation is reasonable, and the district court’s adoption
of it does not constitute clear error.
     Finally, Telebrands alleges that each claim limitation
must be found in the accused product itself, and that it
was clear error for the Magistrate Judge to rely on Bal-
loon Bonanza’s instruction manual to satisfy the shaking
limitation. We disagree. The instructions for the Balloon
Bonanza product are at least circumstantial evidence of
infringement for any claim elements taught by those
materials. A patentee is entitled to rely on circumstantial
evidence to establish infringement: “If [Defendant] is
arguing that proof of inducing infringement or direct
infringement requires direct, as opposed to circumstantial
evidence, we must disagree. It is hornbook law that direct
evidence of a fact is not necessary.” Moleculon Research
Corp. v. CBS, Inc., 793 F.2d 1261, 1272 (Fed. Cir. 1986),
abrogated on other grounds by Egyptian Goddess, Inc. v.
Swisa, Inc., 543 F.3d 665 (Fed. Cir. 2008) (en banc), as
recognized in VirtualAgility Inc. v. Salesforce.com, Inc.,
759 F.3d 1307, 1318 (Fed. Cir. 2014). Indeed, this court
has previously approved of the use of instruction manuals
to demonstrate direct infringement by customers in the
context of induced infringement. Golden Blount, Inc. v.
18     TINNUS ENTERPRISES, LLC   v. TELEBRANDS CORPORATION



Robert H. Peterson Co., 438 F.3d 1354, 1362–63 (Fed. Cir.
2006) (“We reject [Defendant]’s argument that [the pa-
tentee] could not rely on the instruction sheets to prove
acts of direct infringement by end-users.”); see also
Moleculon, 793 F.2d at 1272 (affirming district court’s
finding of induced infringement based, in part, on instruc-
tion sheet).
     The cases Telebrands cites to the contrary are not
persuasive. MicroStrategy stands for the unremarkable
proposition that every claim limitation must be met to
establish literal infringement and says nothing about
product instructions. MicroStrategy Inc. v. Bus. Objects,
S.A., 429 F.3d 1344, 1352–53 (Fed. Cir. 2005). The perti-
nent portion of the Vita-Mix case relates to an induced
infringement analysis where the Plaintiff attempted to
use the accused infringer’s instructions to establish an
intent to induce infringement. Vita-Mix Corp. v. Basic
Holding, Inc., 581 F.3d 1317, 1328 (Fed. Cir. 2009).
There, we disregarded the instructions because they did
not support the inference of intent to infringe, not because
reliance on the instructions would be legally improper.
Id. at 1328–29. We are aware of no case law prohibiting a
court from relying on product instructions to find direct
infringement. Accordingly, the district court did not
clearly err in relying on Telebrands’ instruction manual
as part of its infringement analysis.
                    II. Patent Validity
     “The burden on the accused infringer to show a sub-
stantial question of invalidity at [the preliminary injunc-
tion] stage is lower than what is required to prove
invalidity at trial.” Altana Pharma AG v. Teva Pharm.
USA, Inc., 566 F.3d 999, 1006 (Fed. Cir. 2009). “Vulnera-
bility is the issue at the preliminary injunction stage,
while validity is the issue at trial.” Amazon.com, Inc. v.
Barnesandnoble.com, Inc., 239 F.3d 1343, 1359 (Fed. Cir.
2001). Telebrands contends that the Magistrate Judge
TINNUS ENTERPRISES, LLC   v. TELEBRANDS CORPORATION       19



improperly shifted the burden of proving invalidity to
Telebrands, rather than requiring Tinnus to establish a
likelihood of success in proving the patent’s validity. This
argument is not compelling.
     Each issued patent carries with it a presumption of
validity under 35 U.S.C. § 282. Titan Tire, 566 F.3d at
1376–77. This presumption is sufficient to establish a
likelihood of success on the validity issue, absent a chal-
lenge by the accused infringer. Id. at 1377. Where the
alleged infringer attacks the validity of the patent, “the
burden is on the challenger to come forward with evidence
of invalidity,” which the patentee must then rebut. Id. at
1377–78. “[I]f the trial court concludes there is a ‘sub-
stantial question’ concerning the validity of the patent,
meaning that the alleged infringer has presented an
invalidity defense that the patentee has not shown lacks
substantial merit, it necessarily follows that the patentee
has not succeeded in showing it is likely to succeed at trial
on the merits of the validity issue.” Id. at 1379. The
district court properly applied this analytical framework.
                     A. Indefiniteness
     Telebrands contends that the claim term “substantial-
ly filled” is indefinite because a POSA would not be able
to determine whether an expandable container meets this
limitation. 8
    “[A] patent is invalid for indefiniteness if its claims,
read in light of the specification delineating the patent,
and the prosecution history, fail to inform, with reasona-


    8     Telebrands also argues that “connecting force” is
indefinite, but its argument turns on the indefiniteness of
“substantially filled.” See Appellant Br. 14 (“Without
knowing what volume of water constitutes ‘substantially
filled,’ one skilled in the art cannot know its weight, thus
rendering the ‘connecting force’ indefinite.”).
20     TINNUS ENTERPRISES, LLC   v. TELEBRANDS CORPORATION



ble certainty, those skilled in the art about the scope of
the invention.” Nautilus, Inc. v. Biosig Instruments, Inc.,
134 S. Ct. 2120, 2124 (2014). Because Telebrands did not
object to the R&R’s indefiniteness determination, we
review the district court’s determination on indefiniteness
for plain error. Douglass, 79 F.3d at 1430.
    Telebrands attempts to circumvent this deferential
standard of review by arguing that objecting to the R&R’s
claim construction, or lack thereof, put the Magistrate
Judge on notice that it was contesting the definiteness of
“substantially filled.” We disagree. Nowhere in its objec-
tions to the R&R does Telebrands mention the word
“indefinite,” J.A. 1986–88, and “substantially filled” is not
even among the terms flagged by Telebrands—“attached,”
“connecting force,” “elastic fastener,” and the “shaking”
limitation—as requiring construction. Id. We fail to see
how seeking the construction of different, albeit related,
claim terms would put the district court on notice of
Telebrands’ objection to the R&R’s conclusion that “sub-
stantially filled” was not indefinite.
     Turning to the merits, Telebrands argues on appeal
that the ’066 patent creates a subjective standard for
determining whether a container is “substantially filled”
because the specification makes frequent references to
detaching the containers when they reach a “desired size.”
Appellant Br. 13–14. The specification, however, does not
define or equate “substantially filled” with “desired size.”
And the claims themselves teach that shaking causes the
containers to detach from the hollow tubes when they are
“substantially filled” with water, ’066 patent col. 6 ll. 46–
51, meaning that shaking will not detach the containers if
they are not “substantially filled.” To put a finer point on
it, if the balloons detach after shaking, then they are
“substantially filled.” The R&R cited a portion of this
claim language to support its conclusion that the ’066
patent provided “specific parameters” for determining
TINNUS ENTERPRISES, LLC   v. TELEBRANDS CORPORATION       21



when the containers are “substantially filled.” Magistrate
Op., 2015 WL 11089479, at *5.
     Telebrands alleges that the R&R’s reliance on a por-
tion of this claim language for determining when a con-
tainer is “substantially filled” was based on a truncated
and incorrect reading of the claim. The R&R says, “con-
tainers are substantially filled with water when the
‘water overcomes the connecting force and causes the
containers to detach from the hollow tubes.’” Id. (quoting
’066 patent col. 6 ll. 48–52). According to Telebrands,
shaking, not the water, overcomes the connecting force.
Although shaking does contribute to the detachment, as
discussed above, the claims specifically call for detach-
ment by shaking when the container is “substantially
filled” with water. Thus, we do not find this argument
persuasive.
    In addition to the reasons set forth in the R&R, the
level of ordinary skill in the art plays an important role in
an indefiniteness analysis. Telebrands asserts that a
POSA has “a general knowledge about and experience
with expandable containers, including without limitation
balloons, and at least an associate’s degree in science or
engineering.” J.A. 835–36 ¶¶ 10–13. We find it difficult
to believe that a person with an associate’s degree in a
science or engineering discipline who had read the specifi-
cation and relevant prosecution history would be unable
to determine with reasonable certainty when a water
balloon is “substantially filled.”
    For these reasons, the district court’s conclusion that
Telebrands’ indefiniteness argument failed to raise a
substantial question of validity does not suffer from a
“clear or obvious” error, Ortiz, 806 F.3d at 825–26, requir-
ing reversal under plain error review. Because we find no
clear or obvious error, we need not address the other plain
error factors articulated by the Fifth Circuit in Ortiz.
22       TINNUS ENTERPRISES, LLC   v. TELEBRANDS CORPORATION



                      B. Obviousness
    On appeal, Telebrands advances several arguments
relating to the combination of the Cooper, Saggio, and Lee
references. Because Telebrands did not object to the
factual findings and legal conclusions in the R&R relating
to obviousness, we review the district court’s obviousness
analysis for plain error. 9
    A claim is unpatentable as obvious “if the differences
between the claimed invention and the prior art are such
that the claimed invention as a whole would have been
obvious before the effective filing date of the claimed
invention to a person having ordinary skill in the art.” 35
U.S.C. § 103. The law is clear, however, that “a patent
composed of several elements is not proved obvious mere-
ly by demonstrating that each of its elements was, inde-
pendently, known in the prior art.” KSR Int’l Co. v.
Teleflex Inc., 550 U.S. 398, 418 (2007). Indeed, “it can be
important to identify a reason that would have prompted
a person of ordinary skill in the relevant field to combine
the elements in the way the claimed new invention does.”
Id.
    Telebrands argues that the district court erred be-
cause it found there was no motivation to combine the
prior art references without first considering whether Lee
was reasonably pertinent to the particular problem the
inventor solved. More specifically, Telebrands alleges
that Cooper, Saggio, and Lee each relate to the same
problem addressed by the ’066 patent: “automatically
sealing a balloon or multiple balloons at one time.” Appel-
lant Br. 17–18. A prior art reference is analogous and



     9   Telebrands conceded that plain error review ap-
plies during oral argument. See Oral Arg. at 6:10–6:30,
http://oralarguments.cafc.uscourts.gov/default.aspx?fl=20
16-1410.mp3.
TINNUS ENTERPRISES, LLC   v. TELEBRANDS CORPORATION      23



thus can be used in an obviousness combination if it “is
from the same field of endeavor, regardless of the problem
addressed” or “is reasonably pertinent to the particular
problem with which the inventor is involved,” even if it is
not within the inventor’s field of endeavor. Unwired
Planet, LLC v. Google Inc., 841 F.3d 995, 1000–01 (Fed.
Cir. 2016) (quoting In re Clay, 966 F.2d 656, 658–59 (Fed.
Cir. 1992)). The particular problem confronting the
inventor here was how to rapidly fill multiple containers
with fluid. This is far removed from the problems associ-
ated with an endoscopic balloon insertion device for
treating obesity, and Telebrands has not demonstrated
that Lee is reasonably pertinent to the problem addressed
in the ’066 patent. Therefore, under a plain error review,
we cannot say that the district court committed a clear or
obvious error when it found insufficient motivation to
combine these disparate references. Absent a motivation
to combine, Telebrands’ remaining obviousness argu-
ments are unavailing.
                  III. Irreparable Harm
     Finally, Telebrands alleges that it was clear error for
the Magistrate Judge to rely on evidence pre-dating the
’066 patent’s issuance in support of its finding of irrepa-
rable harm. Citing GAF Building Materials Corp. v. Elk
Corp. of Dallas, 90 F.3d 479 (Fed. Cir. 1996), Telebrands
asserts that irreparable harm must be measured from the
date the patent issues because that is the date on which
the right to exclude others arises. The GAF case is inap-
posite, however, because it addresses the dismissal for
lack of jurisdiction of an action for declaratory judgment
of invalidity and noninfringement of a design patent that
had not yet issued. Id. at 481–83. And Telebrands cites
no case prohibiting reliance on evidence of irreparable
harm pre-dating the patent’s issuance.
   Evidence of consumer confusion, harm to reputation,
and loss of goodwill pre-dating the patent is, at the very
24     TINNUS ENTERPRISES, LLC   v. TELEBRANDS CORPORATION



least, circumstantial evidence demonstrating the possibil-
ity of identical harms once the patent issues. Neither
party has suggested that the issuance of a patent would
somehow mitigate or otherwise eliminate those harms.
Similarly, the pre-issuance price erosion evidence may be
relevant to show what would happen if Balloon Bonanza
was no longer on the market. For example, it might
support an argument that, absent competition, Tinnus
could raise its price back to the original price point, but
would not be able to do so as long as competition from
Balloon Bonanza remains.
    Nonetheless, the irreparable harm analysis does not
depend solely on evidence pre-dating the patent. The
record contains additional evidence of harm after the ’066
patent’s issuance that is sufficient to support a finding of
irreparable harm. For example, a review for Tinnus’s
Bunch O Balloons product on Amazon—dated a few weeks
after the patent issued—states that the customer liked
the “off brand” Bunch O Balloons product better than the
“name brand” Balloon Bonanza. J.A. 1436. This estab-
lishes persisting harm to Tinnus’s reputation and tar-
nishes its status as the innovator in this market. See
Celsis In Vitro, Inc. v. CellzDirect, Inc., 664 F.3d 922, 930
(Fed. Cir. 2012) (“Price erosion, loss of goodwill, damage
to reputation, and loss of business opportunities are all
valid grounds for finding irreparable harm.”). Although
the post-issuance evidence is thinner, we are unable to
find any clear error in the district court’s conclusion that
Tinnus had demonstrated irreparable harm.
                       CONCLUSION
    For the reasons stated above, the district court did
not abuse its discretion in granting the preliminary
injunction. Accordingly, we affirm the district court’s
judgment.
                       AFFIRMED
TINNUS ENTERPRISES, LLC   v. TELEBRANDS CORPORATION   25



                           COSTS
   Costs to Appellees.
