  United States Court of Appeals
      for the Federal Circuit
               __________________________

              METTLER-TOLEDO, INC.,
                 Plaintiff-Appellant,
                            v.
                B-TEK SCALES, LLC,
               Defendant-Cross Appellant.
               __________________________

                    2011-1173, -1200
               __________________________

   Appeals from the United States District Court for the
Eastern District of Texas in case no. 06-CV-0097,
Magistrate Judge Keith F. Giblin.
             ___________________________

               Decided: February 8, 2012
              ___________________________

    JAMES L. KWAK, Standley Law Group, LLP, of Dublin,
Ohio, argued for plaintiff-appellant. With him on the
brief were JEFFREY S. STANDLEY and F. MICHAEL SPEED,
JR.

    RICHARD H. TILGHMAN, IV, Ungaretti & Harris, LLP,
of Chicago, Illinois, argued for defendant-cross appellant.
With him on the brief were F. THOMAS HECHT, RICHARD C.
HIMELHOCH and LISA C. SULLIVAN.
                __________________________
METTLER-TOLEDO   v. B-TEK SCALES                          2


   Before BRYSON, MOORE, and REYNA, Circuit Judges.
MOORE, Circuit Judge.
    Mettler-Toledo, Inc. (Mettler) filed suit accusing B-
Tek Scales, LLC (B-Tek) of infringing claims of U.S.
patent nos. 4,815,547 (’547 patent) and 4,804,052 (’052
patent). After the district court construed the claims, a
jury determined that the claims of the ’547 patent were
not infringed and that the claims of the ’052 patent were
both not infringed and invalid. Mettler appeals the
district court’s denial of Judgment as a Matter of Law
(JMOL) for each of these determinations. Because the
district court correctly construed the claims of the ’547
patent and because substantial evidence supports the
jury’s verdict of invalidity of the ’052 patent, we affirm.
    Cross-Appellant B-Tek appeals the district court’s de-
nial of sanctions for alleged withholding and destruction
of relevant documents. Because the district court did not
abuse its discretion in determining that the documents
were not highly relevant and that there was little harm to
B-Tek, we affirm.
                       BACKGROUND
    The ’547 and ’052 patents relate to technology for
weighing objects, such as large commercial trucks. The
’547 patent describes an individual load cell that is one of
several cells used in a scale. The cell produces an electri-
cal signal in response to being deformed by an external
force such as an object to be weighed. The ’052 patent
describes a system and method for measuring the weight
of moveable objects on a scale. Specifically, the patent
discloses a system for correcting weight measurements
based on the location of objects on a scale. For example,
an object placed at one end of a scale may exert more
pressure on the weight sensors positioned at that end
3                           METTLER-TOLEDO   v. B-TEK SCALES


than an identical object placed in the center. The ’052
patent describes correcting for this load position so that
the same total weight will be determined regardless of the
placement of the object.
    Mettler sued B-Tek alleging infringement of certain
claims of the ’547 and ’052 patents. The district court
construed the claims and the case proceeded to trial
where the jury found that B-Tek did not infringe any of
the asserted claims of the ’547 and ’052 patents. The jury
also determined that the asserted claims of the ’052
patent would have been obvious. Mettler filed a motion
for JMOL on both the infringement and invalidity issues,
which the court denied. Mettler appeals the district
court’s denial of its motion for JMOL for both patents. B-
Tek cross appeals the district court’s denial of sanctions.
We have jurisdiction under 28 U.S.C. § 1295(a)(1).
                       DISCUSSION
    We apply the law of the regional circuit when review-
ing a denial of JMOL. Union Carbide Chems. & Plastics
Tech. Corp. v. Shell Oil Co., 425 F.3d 1366, 1372 (Fed.
Cir. 2005); WMS Gaming Inc. v. Int’l Game Tech., 184
F.3d 1339, 1361 (Fed. Cir. 1999). In the Fifth Circuit,
JMOL is appropriate if the facts and inferences point so
strongly and overwhelmingly in favor of one party that a
reasonable jury could not have concluded otherwise.
Armendariz v. Pinkerton Tobacco Co., 58 F.3d 144, 148
(5th Cir. 1995) (citation omitted). “There must be a
conflict in substantial evidence to create a jury question.”
Id. We have interpreted this standard to mean that a
jury’s determination must be supported by substantial
evidence. Acco Brands, Inc. v. ABA Locks Mfrs. Co., 501
F.3d 1307, 1312-13 (Fed. Cir. 2007). We review claim
construction de novo. Cybor Corp. v. FAS Techs., Inc., 138
F.3d 1448, 1455-56 (Fed. Cir. 1998) (en banc). The words
METTLER-TOLEDO   v. B-TEK SCALES                        4


of a claim are generally given their ordinary and custom-
ary meaning as understood by a person of ordinary skill
in the art when read in the context of the specification
and prosecution history. See Phillips v. AWH Corp., 415
F.3d 1303, 1313 (Fed. Cir. 2005) (en banc).
                      I. ’547 Patent
    The ’547 patent describes a load cell for measuring a
force. ’547 patent col.1 ll.51-53. The cell utilizes a
counterforce attached to a circuit board illustrated in
figure 5:




The circuit includes strain gauges 75, 76, 79 and 80
which, via a bridge circuit, create an analog electrical
signal related to an object’s weight. Id. col.4 ll.62-66.
This analog signal is converted to a digital signal by
“multiple slope integrating analog-to-digital (A/D) con-
verter 100.” Id. col.5 ll.1-2. This digital signal is then
sent to microprocessor 105. Id. col.5 ll.9-15. Claim 1 is
illustrative of the asserted claims:
   Weighing apparatus comprising a counterforce,
   transducer means mounted on said counterforce,
5                          METTLER-TOLEDO   v. B-TEK SCALES


    circuit means associated with said counterforce,
    said circuit means being responsive to external
    control and including means for producing digital
    representations of loads applied to said counter-
    force,
    means for applying at least one correction factor
    to said digital representations and means for
    transmitting said digital representations,
    means providing a sealed enclosure for said
    transducer means and said circuit means,
    means providing a path through said enclosure
    means for external communication with said cir-
    cuit means.
The district court construed a number of the means-plus-
function claim terms including the terms in dispute:
“circuit means associated with said counterforce, said
circuit means being responsive to external control,”
“means for producing digital representations of loads
applied to said counterforce,” and “means for transmitting
said digital representations.” It held that, for each of
these terms, the associated structure in the specification
includes the multiple slope integrating A/D converter, and
equivalents thereof. For example, for the term “means for
producing digital representations of loads applied to said
counterforce,” the district court held that the correspond-
ing structure was “a multiple slope integrating analog-to-
digital (A/D) converter, and equivalents thereof.” Mettler-
Toledo, Inc. v. Fairbanks Scales Inc., 551 F. Supp. 2d 576,
598 (E.D. Tex. 2008).
    In the accused products, the A/D converter is a delta-
sigma A/D converter. The jury determined that the
accused products did not infringe either literally or under
the doctrine of equivalents. In its JMOL motion, Mettler
METTLER-TOLEDO   v. B-TEK SCALES                          6


argued that the delta-sigma A/D converter is equivalent
to the multiple slope integrating A/D converter. The
district court held that substantial evidence supported the
jury’s verdict that they were not equivalent pointing to
trial testimony by B-Tek’s expert and a corporate repre-
sentative from another defendant that there are substan-
tial differences between the two types of converters.
    On appeal, Mettler limits its arguments to a single
claim construction issue: whether the district court im-
properly construed the relevant claim terms to require a
multiple slope integrating A/D converter rather than any
generic A/D converter. Mettler argues that the district
court erred by importing the structure of only the pre-
ferred embodiment or best mode of the disclosure into the
claim. It contends that A/D converters are well-known in
the art and that there was no reason to limit the structure
to only the multiple slope integrating A/D converter. It
further points to figure 5 that illustrates an “Analog to
Digital Converter 100”. It argues that this shows that the
specification discloses generic A/D converters as well as
the more specific multiple slope integrating embodiment.
Mettler contends that the Abstract, by mentioning a
generic A/D converter, supports its broad construction.
Finally, Mettler points out that the district court applied
a different construction for the ’052 patent, holding that a
generic A/D converter is included in the claim term’s
construction. It argues that the two patent specifications
are very similar and both disclose a generic A/D converter
linked to the claimed functions.
    Citing Medical Instrumentation & Diagnostics Corp.
v. Elekta AB, 344 F.3d 1205, 1211 (Fed. Cir. 2003), B-Tek
responds that the patent never links a generic A/D con-
verter to the claimed functions. It points out that the A/D
converter shown in figure 5 is only referred to in the
specification as “multiple slope integrating analog-to-
7                           METTLER-TOLEDO   v. B-TEK SCALES


digital (A/D) converter 100.” ’547 patent col.5 ll.1-2. It
argues that every mention of a converter in the specifica-
tion refers back to this specific type of converter.
    We agree with the district court that the appropriate
structure for the disputed means-plus-function claim
elements in the ’547 patent is the multiple slope integrat-
ing A/D converter and equivalents thereof. Our case law
is clear that a means-plus-function claim limitation is
limited to the structures disclosed in the specification and
equivalents. Med. Instrumentation & Diagnostics, 344
F.3d at 1210. A court must look to the specification to
determine the structures that correspond to the claimed
function. “[S]tructure disclosed in the specification is
‘corresponding’ structure only if the specification or prose-
cution history clearly links or associates that structure to
the function recited in the claim.” B. Braun Med. Inc. v.
Abbott Labs., 124 F.3d 1419, 1424 (Fed. Cir. 1997). If a
patentee chooses to disclose a single embodiment, then
any means-plus-function claim limitation will be limited
to the single disclosed structure and equivalents thereof.
See Nomos Corp. v. Brainlab U.S.A., Inc., 357 F.3d 1364,
1368 (Fed. Cir. 2004).
    The ’547 patent discloses a single embodiment for the
claimed invention that uses a multiple slope integrating
A/D converter. In every instance where the specification
refers to an “A/D converter”, see, e.g., ’547 patent col.5
l.14, it is referring to the preferred embodiment, which
only includes the multiple slope integrating A/D converter
100. Although generic A/D converters were known in the
art, the patentee chose to use means-plus-function lan-
guage which limits it to the disclosed embodiments and
equivalents. While Mettler argues that the district court
erred by limiting it to the “best mode,” the best mode was
also the only structure disclosed in the specification.
METTLER-TOLEDO   v. B-TEK SCALES                           8


    We are not persuaded that the single statement in the
Abstract regarding an “A/D converter” requires a different
result. This disclosure is not linked to any claimed func-
tion as required by our precedent, and therefore does not
support a broader construction. B. Braun Med., 124 F.3d
at 1424. Further, the district court’s different construc-
tion in the ’052 patent is not at odds with its construction
in the ’547 patent. While the two patent specifications
are very similar, the ’052 patent differs in an important
way: in the Summary of the Invention, the ’052 patent
mentions a generic A/D converter and links it to the
claimed function. ’052 patent col.2 ll.21-24. Mettler
relied on this language in its claim construction argument
for the ’052 patent. The district court correctly held that
the ’052 patent linked a generic A/D converter to the
claimed function. In contrast, the ’547 patent does not
include this language and is thus limited to the only A/D
converter that it discloses—the multiple slope integrating
A/D converter. The district court correctly held that the
multiple slope integrating A/D converter was the only
converter disclosed by the ’547 patent and linked to the
claimed functions. Therefore, we affirm the district
court’s denial of JMOL of infringement.
                      II. ’052 Patent
    The ’052 patent teaches a system and method for cor-
rectly measuring the weight of an object regardless of
where that object sits on the scale. ’052 patent col.6 ll.28-
42. This system is particularly useful when measuring
the weight of trucks or other large equipment because the
load will rarely be positioned identically from one meas-
urement to the next. The system includes a number of
load cells (like the one described in the ’547 patent) ar-
ranged around a scale. Depending on the location of the
load to be weighed, these cells will indicate different
weights. The system is calibrated to create an equation
9                           METTLER-TOLEDO   v. B-TEK SCALES


that allows for correction for the differing load positions
so that regardless of the load position, the same weight
will be measured. Id. col.6 ll.52-60.
     The jury found that the ’052 patent was both invalid
for obviousness and not infringed. The district court
denied Mettler’s JMOL motions on both issues. Claim 1
is illustrative:
    Weighing apparatus comprising a plurality of load
    cells,
    load receiving means supported by said load cells,
    means associated with said load cells for providing
    a digital representation of a load on each load cell,
    means for storing a mathematical expression for
    load corrected for load position, and
    means for applying said mathematical expression
    to said digital load representations to produce a
    digital representation of the total load on said
    load receiving means corrected for load position.
Claim 7 is a similar method drawn to “compensating a
multiple load cell scale for load position.”
    The jury returned a verdict that the asserted claims
would have been obvious. On appeal, Mettler argues that
JMOL should have been granted because GB 1,462,808
(Avery) does not teach correcting for load position, which
is a limitation of each asserted claim. Appellant’s Br. 30.
What is disclosed by a prior art reference is a question of
fact. Uniloc USA, Inc. v. Microsoft Corp., 632 F.3d 1292,
1323 (Fed. Cir. 2011); Upjohn Co. v. Mova Pharm. Corp.,
225 F.3d 1306, 1310 (Fed. Cir. 2000). And given the jury
verdict of obviousness, we must presume that the jury
found the facts that support its determination. Upjohn,
225 F.3d at 1310. We conclude that substantial evidence
METTLER-TOLEDO   v. B-TEK SCALES                           10


supports the jury determination that Avery teaches
correcting for load position.
    Avery discloses a system using several transducers to
measure a single load. J.A. 7861 ll.52-61. Using calibra-
tion data (which may be an equation), the system corrects
for an “unevenly loaded” scale. Id. This is sufficient for a
jury to find that it discloses correcting for a load position.
Moving a load to one end of a scale rather than the center
would amount to “uneven loading.” Further, B-Tek’s
expert testified that Avery disclosed this feature, thus
providing more evidence on which the jury could rely.
    Referring only to claim 7, Mettler argues another fac-
tual issue—whether Avery teaches away from the claimed
invention. Spectralytics, Inc. v. Cordis Corp., 649 F.3d
1336, 1343 (Fed. Cir. 2011) (holding that whether the
prior art teaches away from the claimed invention is a
questions of fact). Mettler contends that claim 7 of the
’052 patent explicitly requires “compensating a multiple
load cell scale,” but the Avery reference teaches away
from the claimed invention stating “because the trans-
ducer signals are corrected or adjusted individually . . .
the combined output need not be corrected to compensate
for uneven loading.” J.A. 7862 ll.69-74.
    Read in context, there is substantial evidence for the
jury’s conclusion that Avery does not teach away. Claim 7
requires “compensating a multiple load cell scale.” While
Avery states that it eliminates the need to “compensate
for uneven loading,” it is clearly discussing the timing and
location of any adjustments or corrections. In Avery, each
individual transducer (or load cell) is individually cor-
rected for “uneven loading.” This means that when each
transducer measurement is considered together, there is
no need for additional compensation. Claim 7 of the ’052
patent clearly covers this type of correction. It requires 1)
11                          METTLER-TOLEDO   v. B-TEK SCALES


determining a mathematical expression, 2) interrogating
each load cell (or transducer in Avery) to receive a “digital
load representation,” and 3) “applying said mathematical
expression to said digital load representations.” This
encompasses correcting each individual reading or an
overall reading. Thus, Avery does not teach away from
the claimed invention. 1 Mettler also argues that Avery
fails to teach moving a weight around the scale to cali-
brate the system. Because the claims do not require
moving a weight around the scale, Avery need not ex-
pressly teach this particular calibration technique. We
affirm the district court’s denial of JMOL on the nonobvi-
ousness of the ‘052 patent.
                    III. Cross-Appeal
    B-Tek cross-appeals the district court’s denial of sanc-
tions for alleged discovery abuses by Mettler. We apply
the law of the regional circuit when considering the denial
of sanctions. ClearValue, Inc. v. Pearl River Polymers,
Inc., 560 F.3d 1291, 1304 (Fed. Cir. 2009). Fifth Circuit
precedent requires that we review the district court’s
order for an abuse of discretion. Id. A district court
abuses its discretion when its “ruling is based on an
erroneous view of the law or on a clearly erroneous as-
sessment of the evidence.” Id. Fact findings are not
clearly erroneous unless “the reviewing court on the

     1  B-Tek responds to an argument that Mettler did
not put forth in its opening brief—that Avery fails to
disclose the equation from the ’052 patent that the court
construed to be a part of a means-plus-function limitation.
Avery discloses that “[t]he calibration data may, for
example, be in the form of factors to be multiplied and/or
algebraically summated with the respective transducer
output.” Avery p.2 ll.45-50. This amounts to substantial
evidence because it is simply a prosaic description of the
equation disclosed in the ’052 patent.
METTLER-TOLEDO   v. B-TEK SCALES                         12


entire evidence is left with the definite and firm convic-
tion that a mistake has been committed.” Anderson v.
City of Bessemer City, 470 U.S. 564, 573 (1985).
    In order to develop its case rebutting lost profits dam-
ages, B-Tek requested documents related to Mettler’s
manufacturing capacity. Mettler stated that it had no
such documents. During trial, a Mettler employee admit-
ted that certain documents existed—a production sched-
ule and a plant diagram—and that some of these
documents had been destroyed. Further, Mettler admit-
ted that it provided some of these documents to its own
damages expert during the preparation of its case show-
ing that Mettler appreciated the documents’ relevance. B-
Tek moved for sanctions, including attorney’s fees. The
district court denied the motion. It noted that Mettler did
not hide the documents because Mettler’s representative,
in a deposition, spoke about manufacturing capability and
mentioned the production schedule. Further, the district
court found that the documents were not particularly
relevant, stating:
   Production schedules are, as the court under-
   stands them, merely an ever-changing, real-time
   representation of Mettler-Toledo’s backlog, and
   unlikely to provide much, if any, relevant infor-
   mation about manufacturing capacity. Nor does
   the court see how a physical layout diagram of the
   Masstron facility would be relevant.
J.A. 170. The district court also noted that B-Tek could
not show the requisite harm or prejudice because “[B-Tek]
ultimately prevailed at trial on the issue of infringement”
so it did not have to rely on its damages case. Id. Thus,
the court held “assuming there was a discovery violation
at all, which is somewhat doubtful, it does not rise to the
level of sanctionable behavior under Rule 37.” Id.
13                         METTLER-TOLEDO   v. B-TEK SCALES


    We hold that the district court did not abuse its dis-
cretion. It correctly considered the relevance of the docu-
ments and any harm to B-Tek due to the withholding.
The district court determined that the documents in
question were, at best, only somewhat relevant. The
court also concluded that there was no harm to B-Tek. B-
Tek cannot point to any “erroneous view of the law or [ ] a
clearly erroneous assessment of the evidence” and, thus,
we affirm. ClearValue, 560 F.3d at 1304.
                      AFFIRMED
                          COSTS
     No costs.
