  United States Court of Appeals
      for the Federal Circuit
                ______________________

               CHEESE SYSTEMS, INC.,
      Plaintiff/Counterclaim Defendant-Appellant,

                         AND

   CUSTOM FABRICATING AND REPAIR, INC.,
        Counterclaim Defendant-Appellant,

                           v.

  TETRA PAK CHEESE AND POWDER SYSTEMS,
 INC. AND TETRA LAVAL HOLDINGS & FINANCE
                       S.A.,
       Defendants/Counterclaimants-Appellees.
              ______________________

                   2012-1463, -1501
                ______________________

   Appeals from the United States District Court for the
Western District of Wisconsin in No. 11-CV-0021, Senior
Judge Barbara B. Crabb.
                ______________________

                Decided: August 6, 2013
                ______________________

    JOHN P. FREDRICKSON, Boyle Fredrickson, S.C., of
Milwaukee, Wisconsin, argued for plaintiff/counterclaim
defendant-appellant  and    counterclaim     defendant-
2                  CHEESE SYSTEMS, INC.   v. TETRA PAK CHEESE

appellant. With him on the brief were JAMES F. BOYLE,
MICHAEL T. GRIGGS, and ERIC J. LALOR.

    PHILIP L. HIRSCHHORN, Buchanan Ingersoll & Rooney
PC, of New York, New York, argued for defend-
ants/counterclaimants-appellees. With him on the brief
were S. LLOYD SMITH and RACHEL ELSBY, of Alexandria,
Virginia. Of counsel on the brief were JEFFREY S. WARD,
EDWARD J. PARDON, and SHANE BRUNNER, Merchant &
Gould P.C., of Madison, Wisconsin.
                 ______________________

    Before RADER, Chief Judge, REYNA, Circuit Judge, and
                   DAVIS, District Judge. *
RADER, Chief Judge.
     In this declaratory judgment action, the United States
District Court for the Western District of Wisconsin
granted the summary judgment motion of Tetra Pak
Cheese and Powder Systems (Tetra Pack Cheese) and
Treval Laval Holdings & Finance S.A (Treval Laval)
(collectively, Tetra Pak) against Cheese Systems, Inc.
(CSI). In an unpublished fifty-four page opinion, the trial
court determined that CSI infringed under the doctrine of
equivalents and had not proven the ’347 patent invalid.
Cheese Sys., Inc. v. Tetra Pak Cheese and Powder Sys.,
Inc. and Tetra Laval Holdings & Fin. S.A., No. 11-cv-21-
bbc (W.D. Wis. May 15, 2012); J.A. 1–54 (Slip Op.). By
stipulation, the district court also entered a permanent
injunction against CSI. Slip Op. at 55–58. Because the
District Court correctly applied the law to these facts, this
court affirms.



     Honorable Leonard Davis, Chief District Judge,
     *

United States District Court for the Eastern District of
Texas, sitting by designation.
CHEESE SYSTEMS, INC.   v. TETRA PAK CHEESE                3
                              I.
    The subject matter of this patent involves commercial
cheese-making vats. To make cheese, the technology
combines milk and other additives in a vat. That process
heats, cools, cuts, and stirs the ingredients to make
cheese. At length, the ingredients solidify into a semi-
solid mass called “coagulum.” Slip Op. at 5.
    The panels inside the vat that cut and stir the coagu-
lum are called “agitators,” “agitator panels,” or “paddles.”
Agitator panels are two-sided panels, one side with rela-
tively sharp cutting edges, and the other side with com-
paratively blunt stirring edges. Electric motors drive the
panels via long shafts that pass through the vat walls.
During operation the electric motors rotate the shafts,
causing the attached panels to stir, or to cut, the coagu-
lum. The panels have ample openings between the cut-
ting or stirring blades to allow coagulum to pass through
the panels as they move through the coagulum. This cut-
away view from a prior art patent illustrates the general
structure of a horizontal vat:




U.S. Pat. No. 4,989,504, Fig. 1 (the Jay ’504 Patent).
4                  CHEESE SYSTEMS, INC.   v. TETRA PAK CHEESE
    In cheese-making parlance, vats may be open or
closed, and horizontal or vertical. A vat is “closed” if it
has no large opening at its top. See id. at col. 1, ll. 17–25.
The key distinction between horizontal and vertical
cheese vats is the orientation of the agitator shafts: in
vertical vats, agitator shafts are generally perpendicular
to the ground, while in horizontal vats, they are generally
parallel to the ground. (Figure 1, above, depicts a hori-
zontal vat.) Horizontal vats may not lie literally horizon-
tal to the floor, but instead may tilt slightly toward one
end in order to facilitate draining. See, e.g., id. Fig. 2.
    Until somewhat recently, cheese vats were predomi-
nantly oriented vertically. See id. at col. 1, ll. 25–60.
However, cheese-makers recognized that vertical vats
suffered efficiency and quality losses as the size of the
vats increased. See id. To cure these ills, cheese makers
essentially turned closed vertical vats on their sides, to
become horizontal vats. See id. at col. 1, ll. 50–60.
     In these horizontal vats, prior art taught that the
shafts should “co-rotate” meaning turn in the same direc-
tion. Co-rotating horizontal vats improved vertical vats,
but still presented problems. For instance, curds piled up
on the bottom side of the vat where the agitator panels
would both be moving upward. See ’347 patent col. 22, ll.
44–49. Also, co-rotation caused the coagulum to flow in
the same direction, which required quicker rotation of the
panels in order to “catch up” with and cut the coagulum.
Often the co-rotating horizontal vats suffered from ineffi-
cient cutting and other quality problems. See id. at col. 1,
l. 64 to col. 2, l. 8.
    The ’347 patent addressed these problems with two
improvements. First, the patent teaches contra-rotating
the shafts (also called counter-rotating) not co-rotating.
See ’347 patent col. 3, ll. 28–31. The ’347 patent describes
counter-rotation by referring to the movement of the
CHEESE SYSTEMS, INC.   v. TETRA PAK CHEESE               5
blades through the space where the two interconnected
chambers overlap, called the “common volume:”




    When shafts co-rotate, they move in opposite direc-
tions through the common volume; with counter-rotation,
they move in the same direction through the common
volume. With co-rotation, because the agitator panels
have cutting faces on the same side, this means that when
one set of agitator panels goes upward and cuts through
the common volume, the other goes downward and cuts
through the common volume, and vice versa in the stir-
ring mode. Put another way, co-rotating agitator panels
perform the same task (cutting or stirring), while going
the opposite direction through the common volume. With
counter-rotation, the panels move the same direction
through the common volume: both downward, or both
upward.
    Second, the patent arranges the panels so that during
contra-rotation, both panels present only cutting or only
stirring faces to the common volume. See id. at col. 18–
17. In the claimed vat, the panels are fitted so that, even
though the shafts turn in opposite directions, only cutting
6                  CHEESE SYSTEMS, INC.   v. TETRA PAK CHEESE
or only stirring action occurred as they passed through
the common volume. Without this change, a vat with
contra-rotating shafts would both cut and stir at the same
time.
    These innovations operated to ensure that only cut-
ting or only stirring would occur as the panels move in
opposite directions through the common volume. The ’347
patent explains that the key is not just that the shafts
contra-rotate, but instead it is the combination of contra-
rotation combined with presenting only cutting or only
stirring edges while moving the same direction through
the common volume. Id. at 27–31. The patent explains
that the panels’ direction through the common volume—
moving upward while cutting or downward while cut-
ting—can be determined according to the desired qualities
of the cheese product. Id. at 10–31.
    The ’347 patent was filed in March, 1998 and issued
in November, 1999. CSI brought this declaratory judg-
ment action in January 2011. J.A. 84. In the district
court, Tetra Pak asserted that CSI infringed claims 1, 2,
3, 9, 10, 11 and 12 of the ’347 patent. Claims 1 and 10 are
independent. Claim 1 defines an apparatus; claim 10 a
method. This appeal focuses on claim 1:
    In a cheese processing vat having a pair of inter-
    connected generally cylindrical wall portions with
    horizontally disposed axes, the axes of the gener-
    ally cylindrical wall portions positioned in parallel
    horizontally spaced relation, and common opposite
    end walls forming with the generally cylindrical
    wall portions an enclosed vat containing a mixture
    of cheese curd solids and liquid whey, said vat
    having a generally oval cross section in a plane
    perpendicular to said axes, the improvement com-
    prising:
CHEESE SYSTEMS, INC.   v. TETRA PAK CHEESE              7
       An agitator panel rotably mounted on the
       axis of each wall portion to sweep a gener-
       ally cylindrical volume;
       each agitator panel including a cutting
       face having a plurality of sharp cutting
       edges disposed in a generally common first
       plane and an opposite stirring face having
       a plurality of blunt stirring edges disposed
       in a generally common second plane;
       a drive for rotating said panels in the op-
       posite rotational direction through the
       mixture in the vat such that said panels
       move through the common volume in the
       same direction, and means for mounting
       said panels with the respective cutting
       and stirring edges oriented such that dur-
       ing rotation only the stirring edges of the
       panels or only the cutting edges of the
       panels are moving toward the common
       volume and such that one of said panels
       trails the other of said panels during
       movement through said common volume.
   ’347 patent, col. 8, ll. 28–57.
    As noted, Tetra Pak accused CSI’s High Solids Cheese
Vat (HSCV) of infringement. CSI’s HSCV is an enclosed
cheese vat, with two shafts running generally horizontal
to the ground, with the counter-rotational shafts driven
by an electric motor. J.A. 1424, 1429. When the shafts
rotate, only cutting, or only stirring, takes place. J.A.
1425–26. Each shaft holds a series of curved “paddles,”
which have one side sharpened to cut and the other side
relatively blunt to stir. A 1427–28. The first photo below
shows the outside of the accused vat, and the second
shows the interior, including CSI’s curved paddles:
8                 CHEESE SYSTEMS, INC.   v. TETRA PAK CHEESE




Appellants’ Br. 16, 15.
       As noted earlier, CSI filed this declaratory judg-
ment action and pled that it did not infringe and that the
CHEESE SYSTEMS, INC.   v. TETRA PAK CHEESE               9
asserted claims were invalid. Tetra Laval owns the ’347
patent and Tetra Pak is its exclusive licensee. Tetra Pak
filed a counterclaim, alleging that CSI infringed the ’347
patent. Along with striking a portion of a CSI expert’s
declaration, the district court granted summary judgment
that the claims were not invalid and were infringed. Slip
Op. at 1–54.
     CSI appeals, arguing the district court erred in three
aspects of claim construction, in finding infringement as a
matter of law, and in denying summary judgment of
invalidity based upon CSI’s defenses of anticipation and
obviousness. CSI also challenges the striking of CSI’s
late-filed expert testimony relating to obviousness. The
court has jurisdiction under 28 U.S.C. §§ 1292(a)(1) and
(c)(1).
                              II.
    This court reviews a grant of summary judgment in
accordance with regional circuit law. Serdarevic v. Ad-
vanced Med. Optics, Inc., 532 F.3d 1352, 1362 (Fed. Cir.
2008). Under controlling Seventh Circuit precedent, a
district court must draw every reasonable inference in
favor of the non-moving party and grant summary judg-
ment only if no reasonable jury could find in favor of the
non-moving party. See Stoner v. Wisc. Dep’t of Agric.,
Trade & Consumer Prot., 50 F.3d 481, 484 (7th Cir. 1995).
This court reviews the grant of summary judgment with-
out deference, applying the same standard as the district
court. See Lexion Med., LLC v. Northgate Techs., Inc., 641
F.3d 1352, 1357 (Fed. Cir. 2011).
     Claim construction presents only legal questions. Cy-
bor Corp. v. FAS Techs., Inc., 138 F.3d 1448, 1455 (Fed.
Cir. 1998). Anticipation and infringement are questions
of fact. Osram Sylvania, Inc. v. Am. Induction Tech., Inc.,
701 F.3d 698 (Fed. Cir. 2012) (anticipation); Roton Barri-
er, Inc. v. Stanley Works, 79 F.3d 1112, 1125 (Fed. Cir.
1996) (infringement). A determination of obviousness is
10                 CHEESE SYSTEMS, INC.   v. TETRA PAK CHEESE
based on underlying factual findings, including “(1) the
scope and content of the prior art; (2) the level of ordinary
skill in the pertinent art; (3) the differences between the
claimed invention and the prior art; and (4) the evidence
of secondary factors, such as commercial success, long-felt
need, and the failure of others.” Daiichi Sankyo Co. v.
Matrix Labs., Ltd., 619 F.3d 1346, 1352 (Fed. Cir. 2010)
(citing Graham v. John Deere Co., 383 U.S. 1, 17–18
(1966)). The factual findings underlying summary judg-
ment of nonobviousness are reviewed under the summary
judgment standard, and the ultimate determination of
obviousness is a legal conclusion reviewed without defer-
ence. See Golight, Inc. v. Wal-Mart Stores, Inc., 355 F.3d
1327, 1336 (Fed. Cir. 2004).
    In examining whether a district court properly grants
a motion to strike testimony as a discovery sanction, this
court applies regional circuit law. Transclean Corp. v.
Bridgewood Servs., Inc., 290 F.3d 1364, 1373 (Fed. Cir.
2002). The Seventh Circuit reviews for abuse of discre-
tion. Musser v. Gentiva Health Servs., 356 F.3d 751, 755
(7th Cir. 2004). Likewise, a district court's decision to
preclude expert testimony is an evidentiary issue that is
reviewed for an abuse of discretion. Gen. Elec. Co. v.
Joiner, 522 U.S. 136, 141–43 (1997) (“[A]buse of discretion
is the proper standard of review of a district court's evi-
dentiary rulings.”); Flex-Rest, LLC v. Steelcase, Inc., 455
F.3d 1351, 1357 (Fed. Cir. 2006) (applying Joiner).
                            III.
     Direct infringement requires proof by preponderant
evidence that the defendant performs (if a method claim)
or uses (if a product claim) each element of a claim, either
literally or under the doctrine of equivalents. See BMC
Resources, Inc. v. Paymentech, L.P., 498 F.3d 1373, 1381
(Fed. Cir. 2007). The district court found no disputed
issue of material fact and that CSI’s HSCV vats infringed
at least claims 1 and 10 of the ’347 patent.
CHEESE SYSTEMS, INC.   v. TETRA PAK CHEESE               11
    On appeal, CSI argues three grounds to reverse.
First, it asserts that its HSCV does not have cutting
panels that meet the “generally common plane” limita-
tion. Second, it asserts that its paddles do not satisfy the
“agitator panel” limitation. And, third, that the accused
vat does not satisfy the “horizontally disposed axes”
limitation.
     The claims require that the agitator panel have “a
plurality of sharp cutting edges disposed in a generally
common first plane,” and “a plurality of blunt stirring
edges disposed in a generally common second plane.” The
district court construed the phrase “generally common
plane” to require panel “surfaces that are on the whole
flat but include some degree of curvature.” Slip Op. at 23.
This claim language requires each agitator panel to have
a plurality of sharp (or blunt) edges in a generally com-
mon plane. The district court correctly assessed that a
plurality simply means two or more. Slip Op. at 28. A
plane refers to a flat surface. With these understandings,
a requirement that the entire panel be “on the whole flat”
is too restrictive because it requires far more than a
plurality of edges in the same general plane. This court
instead concludes that the claim language does not re-
quire the panel to have any particular shape beyond the
requirement that more than two cutting and stirring
edges lie in respective generally common planes.
    The claim also requires that only the stirring, or only
the cutting, edges of the panel move through the common
volume in a given operation. This court also finds nothing
in the specification giving any special meaning to this
claim phrase. Moreover, the prosecution history does not
show any surrender of claimed subject matter, let alone
clear and unmistakable evidence of such disavowal.
    On infringement of this limitation, Tetra Pack argues
that this court can affirm either via the doctrine of equiv-
alents or by finding literal infringement as a matter of
12                CHEESE SYSTEMS, INC.   v. TETRA PAK CHEESE
law. Appellee’s Br. 31–35. This court affirms on the
ground that the accused products literally infringe this
element and so does not reach the alternative ground of
infringement under the doctrine of equivalents. Hydril
Co. LP v. Grant Prideco LP, 474 F.3d 1344, 1351 (Fed.
Cir. 2007) (noting that it is within this court’s discretion
to “affirm a district court judgment on any ground shown
by the record, even though that was not the basis of the
district court's decision.”).
    The district court found a fact question on literal in-
fringement, and so denied Tetra Pak summary judgment
on that ground. Slip Op. at 26. The district court reached
this conclusion only by unduly limiting the language to
require that the panels be “on the whole flat.” To the
contrary, this element requires only that a plurality of
cutting edges lie in a generally common plane. In the
accused device, a plurality of stirring edges falls in the
same plane. Thus, the record amply supports that the
accused products meet that limitation, as a visual inspec-
tion confirms:
CHEESE SYSTEMS, INC.   v. TETRA PAK CHEESE                 13
Appellants’ Br. 16. Accordingly, this court reverses the
denial of summary judgment of no literal infringement.
This court need not reach the questions of equivalency or
prosecution history estoppel.
    Claim 1 also uses the word “agitator panel” and “pan-
els” at least once in every element of the claim. ’347
patent, col. 8, ll. 38–57. Those skilled in the art, including
CSI’s own expert, Mr. Jay, acknowledged that multiple
panels can be present on a single shaft, and that in this
art each separate panel is, not surprisingly, a separate
“agitator panel.” Slip Op. at 28–29; see also J.A. 1793.
The specification also stated that the shaft provides “a
pair of radial support arms by which the panel is mounted
for rotation.” ’347 patent col. 5, ll. 33–34. Based upon
this, the district court construed the phrase “agitator
panel” to include “a structure of blades rotably mounted
on the axis of the cylindrical vat to cut and stir the coagu-
lum.” Slip Op. at 29.
    The record amply supports the district court’s inter-
pretation of this claim term. CSI’s alternative would have
construed “agitator panel” to mean the entire structure
that rotates to agitate the mixture, which includes some
panels presenting cutting edges and some panels present-
ing stirring edges when rotated in a given direction. See
Slip Op. at 27; Appellants’ Br. 41. As a consequence, the
cutting edges from two adjacent panels would not be
“disposed in a generally common . . . plane,” as, for exam-
ple, in the photo of CSI’s accused vat, above. The district
court correctly dismissed those arguments. Slip Op. at
27. The district court correctly held no reasonable juror
could find that CSI’s agitator panels do not meet this
limitation. Slip Op. at 30. Therefore, the record shows
that the district court properly entered summary judg-
ment of literal infringement with respect to this limita-
tion.
14                 CHEESE SYSTEMS, INC.   v. TETRA PAK CHEESE
    This court next addresses the emphasized language in
the phrase, a cheese vat with “a pair of interconnected
generally cylindrical wall portions with horizontally
disposed axes.” ’347 patent col. 8, ll. 29–31 & col. 9, ll. 25–
26 (emphasis added). The record shows, and the district
court found, that “[m]any horizontal cheese vats have a
slight incline relative to the ground to facilitate draining,
which they achieve by placing the vat body on a stand
with longer legs at one end.” Slip Op. at 31. CSI’s expert
witness described vats with slight inclines as “horizontal
vats.” See Slip Op. at 31–32.
    Relying on this evidence, the district court held that a
person of ordinary skill would read this limitation to
mean “oriented generally with respect to the ground, as
compared to axes generally vertically with respect to the
ground.” Slip Op. at 31. Thus, the district court found
that a person of ordinary skill in this art “would distin-
guish horizontal from vertical cheese vats in comparative
terms, rather than requiring horizontal vats to be precisely
horizontal.” Id. (emphasis added). In addition, Figure 8
from CSI’s own Jay ’540 Patent describes the depicted vat
as “horizontal” even though it has a slight angle. ’540
patent Fig. 8.
    Despite the abundant record on this point, CSI argues
that the axes must be “exactly parallel to the ground.”
Appellants’ Br. 47. CSI notes that some horizontal vats
have a concave bottom and are drained through it and are
truly horizontal to the ground. Id. In addition, CSI
emphasizes that in some places the patent uses the “gen-
erally” as a modifier, but it does not do so for this limita-
tion. Id. at 47–51.
     This court concludes that the record supports the dis-
trict court’s interpretation. Indeed, a person of ordinary
skill in this art would understand “horizontal” as a term
used to distinguish horizontal vats from vertical ones, not
to require precise horizontal orientation of the shafts.
CHEESE SYSTEMS, INC.   v. TETRA PAK CHEESE                15
Thus, the claim term “horizontal” in this art permits some
degree of incline. Thus, this court affirms the trial court’s
determination that the term means “generally oriented
horizontally with respect to the ground.” Moreover, the
district court correctly held that no reasonable jury could
fail to find that the HSCV product meets this limitation.
See id. at 31. Accordingly, the district court properly
granted summary judgment to Tetra Pak of literal in-
fringement with respect to this element.
                             IV.
    The court turns to CSI’s invalidity defenses. While
CSI raised other grounds of invalidity below, it appeals
only the grant of summary judgment to Tetra Pak con-
cerning anticipation and obviousness.
    Anticipation requires clear and convincing proof that
a single prior art reference “not only disclose[s] all of the
elements of the claim within the four corners of the docu-
ment, but . . . also disclose[s] those elements arranged as
in the claim.” Net MoneyIn, Inc. v. Verisign, Inc., 545 F.3d
1359, 1369 (Fed. Cir. 2008). CSI asserts that two of the
Jay patents discussed in the specification of the patent-in-
suit and considered by the examiner—the ’559 and
the ’907 patents—each anticipates every asserted claim.
See Appellants’ Br. 51; Reply Br. 18–22.
    The Jay ’559 patent issued off an application filed in
May 1995; the Jay ’906 patent issued off a CIP of that
application, filed in May, 1996. So far as is pertinent
here, they have identical disclosures. Appellants’ Br. 52
n.4. These two patents relate to improvements to hori-
zontal vats for semi-liquid food products, including, but
not limited to, cheese. Id. Specifically, the patents relate
to an improved blade structure. See Jay ’559 Patent Fig.
2.
    These patents describe the benefits that the new
blade structure brings to solving one problem caused by
16                CHEESE SYSTEMS, INC.   v. TETRA PAK CHEESE
co-rotation. They explain that the “overall agitation
pattern is such that the contents of the vat will be in-
duced to rotate in the same direction as the agitator with
significant cross-cutting action and other interactions in
the zone where the agitator panels overlap.” Jay ’559
patent at col. 2, l. 65 to col. 3, l. 2. The patents explain
that cross-cutting occurs because the panel on one axis
cuts the common volume in an upward direction while the
panel on the other axis cuts it in a downward direction—
precisely the circumstance of co-rotation. The patent
emphasizes that the improved blade increases cross-
cutting and so improves cheese production because the
shafts can spin at lower speeds.
    Though extolling the virtues of the improved blade in
a co-rotating environment, the Jay patents do mention
counter-rotation, stating that “[a]gitators normally rotate
co-directionally but can be arranged for counter rotation
where specific production criteria demand it.” Id. at col.
3, ll. 26–28. The specification, including the claims,
makes no further mention of counter-rotation. The pa-
tents make no mention—at all—of switching the orienta-
tion of the panels on one shaft so that, if counter-rotated,
the cutting surfaces of one set of agitator panels will be
moving through the common volume in the same direction
as the cutting faces of panels on the other shaft.
    The district court correctly recognized that neither
patent discloses means to mount panels so that during
counter-rotation only cutting or only stirring edges move
through the common volume. Slip Op. at 41 (correctly
stating that the two Jay patents “say nothing about
reorienting the panels”). CSI does not address this glar-
ing shortcoming in its anticipation argument. Instead,
CSI notes that the panels depicted in Figure 2 of the
Jay ’559 patent are very similar to those depicted in
Figure 2 of the ’347 patent. See Appellants’ Br. 52. CSI
argues that a person of ordinary skill would read these
Jay patents, see they mention that the panels “can be
CHEESE SYSTEMS, INC.   v. TETRA PAK CHEESE              17
arranged” for contra-rotation if “specification production
criteria demand it,” and argues that this can mean, only,
to mount the panels so that only cutting or only stirring
occurs. Appellants’ Br. at 54; Reply Br. 21.
    Even construing ambiguities in CSI’s favor, the
phrase “can be arranged” suggests altering the mounts for
the panels rather than altering rotation of the shafts to
allow for counter-rotation. Nothing in these Jay patents
states that if counter-rotation is used, the panels on one
shaft should be, let alone must be, reversed. The patents
teach only that contra-rotation should be used if “specific
production criteria” demand it, but these patents are not
directed solely to cheese production, but instead include
other food products. See Slip Op. at 41. Thus the Jay
specification reads most consistently as suggesting that
other food products benefit from simultaneous cutting and
stirring. Without a clear and unambiguous teaching, a
jury could only speculate, hardly a compelling case for
anticipation.
    CSI’s other arguments are equally unpersuasive. For
these reasons, these Jay patents do not anticipate, either
expressly or inherently. The district court correctly
granted summary judgment to Tetra Pak. Slip Op. at 42.
    The district court also granted summary judgment
that the ’347 patent would not have been obvious at the
time of invention. CSI asserted obviousness based on
several combinations of art, including the three Jay
patents along with the AT ’523 patent and EP ’587 patent.
Slip Op. at 43. The examiner considered the three Jay
patents before granting the patent. CSI produced testi-
mony about the AT ’523 and EP ’587 patents largely after
the discovery cut-off and, therefore, the district court
excluded much of that evidence. See Slip Op. at 2–4, 45.
After a careful analysis, the district court rejected CSI’s
obviousness defense. See Slip Op. at 42–53.
18                CHEESE SYSTEMS, INC.   v. TETRA PAK CHEESE
    Under 35 U.S.C. § 103(a), a patent is invalid “if the
differences between the [claimed] subject matter . . . and
the prior art are such that the subject matter as a whole
would have been obvious at the time the invention was
made to a person having ordinary skill in the art to which
said subject matter pertains.” While obviousness is a
determination of law, it is based on the underlying deter-
minations of fact mentioned above. See Geo M. Martin
Co. v. Alliance Mach. Sys. Int'l, 618 F.3d 1294, 1300 (Fed.
Cir. 2010); KSR Int'l Co. v. Teleflex, Inc., 550 U.S. 398,
406 (2007) (citing Graham v. John Deere Co., 383 U.S. 1,
17–18 (1966)).
    Whether a claim is invalid for obviousness is deter-
mined from the perspective of one of ordinary skill in the
art. Id. at 420 (“The question is not whether the combina-
tion was obvious to the patentee but whether the combi-
nation was obvious to a person with ordinary skill in the
art.”). Even when all claim limitations are found in prior
art references, the fact-finder must determine what the
prior art teaches, whether prior art teaches away from the
claimed invention, and whether there was motivation to
combine teachings from separate references. See DyStar
Textilfarben GmbH & Co. Deutschland KG v. C.H. Patrick
Co., 464 F.3d 1356, 1360 (Fed. Cir. 2006); see KSR, 550
U.S. at 421–22 (discussing Dystar).
    Among the difficult challenges of applying the doc-
trine of obviousness is avoidance of even a hint of hind-
sight. Obviousness “cannot be based on the hindsight
combination of components selectively culled from the
prior art to fit the parameters of the patented invention.”
ATD Corp. v. Lydall, Inc., 159 F.3d 534, 546 (Fed. Cir.
1998). In this regard, objective evidence operates as a
beneficial check on hindsight. As the court recently
explained in describing these “essential components” of
the obviousness analysis:
CHEESE SYSTEMS, INC.   v. TETRA PAK CHEESE               19
   Objective evidence of nonobviousness can include
   copying, long felt but unsolved need, failure of
   others, commercial success, unexpected results
   created by the claimed invention, unexpected
   properties of the claimed invention, licenses show-
   ing industry respect for the invention, and skepti-
   cism of skilled artisans before the invention.
   These objective considerations can protect against
   the prejudice of hindsight bias, which often over-
   looks that “[t]he genius of invention is often a
   combination of known elements which in hind-
   sight seems preordained.” McGinley v. Franklin
   Sports, Inc., 262 F.3d 1339, 1351 (Fed. Cir. 2001).
Power Integrations, Inc. v. Fairchild Semiconductor Int’l,
Inc., 711 F.3d 1348, 1368 (Fed. Cir. 2013) (citations omit-
ted).
     At the outset, although the district court recognized
that objective considerations of nonobviousness are a
required part of this analysis, Slip Op. at 42 (citing Gra-
ham v. John Deer Co., 383 U.S. 1, 17–18 (1966)), the
district court did not expressly consider and make specific
findings on those factors. Where a court holds a claim
obvious without making findings of secondary considera-
tions, the lack of specific consideration of secondary
considerations ordinarily requires a remand. OSRAM
Sylvania, Inc. v. Am. Induction Techs., Inc., 701 F.3d 698,
708–09 (Fed. Cir. 2012). Even where, as here, a district
court upholds a claim over an assertion of obviousness, a
trial court may prevent remands by making these poten-
tially crucial fact-findings. See Ortho-McNeil Pharma.,
Inc. v. Myland Labs., Inc., 520 F.3d 1358 (Fed. Cir. 2008)
(explaining that objective evidence of nonobviousness “is
not just a cumulative or confirmatory part of the obvious-
ness calculus but constitutes independent evidence of
nonobviousness.”). Under some circumstances, this court
may not be able to adequately review an appeal of even
nonobviousness without fact findings on objective consid-
20                 CHEESE SYSTEMS, INC.   v. TETRA PAK CHEESE
erations because they are a part of—not in addition to—
the analysis. In this case, however, for the following
reasons, this court affirms the grant of summary judg-
ment without a remand.
    CSI first asserted that the Jay ’559 and ’907 patents
would have rendered the invention in the asserted claims
of the ’347 patent obvious in light of the Jay ’504 patent.
Appellants’ Br. 56–59. CSI asserts that, because contra-
rotation was disclosed in the art, it would have been
obvious to flip the orientation of the panels on one shaft so
that the panels did not cut and stir simultaneously. Id. at
57. Like the district court, this court rejects this argu-
ment.
    As explained above, the Jay ’559 and ’507 patents
have essentially identical disclosures. The third Jay
patent, U.S. Patent No. 4,989,504 (the Jay ’504 patent)
discloses an improvement to enclosed horizontal vats to
avoid air contamination and have less heat loss consisting
of using a series of distinct “paddles” attached in stag-
gered rows wrapped spirally around a shaft, with each
paddle having a slight angle. The Jay ’504 patent’s
specification states that the blades are sharpened on one
side only and presented so that when rotated only cutting
surfaces or only stirring surfaces are presented. Jay ’504
patent at col. 2, ll. 45–52. A passage in the specification
states:
     The stirring action is further enhanced by means
     of an angle of impingement . . . such that when ro-
     tated in the stirring direction these blades act on
     the product in a propeller like manner creating a
     generally torroidal flow pattern around the shaft
     of each inner wall section. The direction of rota-
     tion of the shafts is normally the same such that
     the flow patterns collide in the common second
     portion of the swept volumes of the inner wall sec-
     tions. In another form the invention, the shafts
CHEESE SYSTEMS, INC.   v. TETRA PAK CHEESE                 21
    are arranged to contra rotate thereby creating op-
    posite torroidal flow patterns around each of the
    shafts in the vat such that the flow patterns are in
    unison in the common second portion of the swept
    volumes of the inner wall sections.
Jay ’504 patent, Col. 2, ll. 52–66 (emphasis added). The
specification makes no further mention of counter-
rotation, but instead explains the benefits of co-rotation.
Further, the Jay ’504 patent makes no mention of switch-
ing the orientation of the panels so that, if counter-
rotated, the cutting surfaces of one set of agitator panels
will be moving through the common volume in the same
direction as the other panels and only cutting or stirring.
In other words, if a person of skill in the art followed the
Jay ’504 patent and arranged the shafts to contra-rotate,
both cutting and stirring would occur at the same time.
    The district court recognized that nothing in the pa-
tents discloses means to mount the panels in the opposite
direction, let alone any guidance to do so. Slip Op. at 49–
53. Further, the district court correctly noted that
the ’559 and ’907 patents do not say anything else about
counter rotation, do not explain what production criteria
might require it, do not explain any benefit to counter-
rotation (only why co-rotation is good), and do not ex-
pressly describe means to arrange the panels to avoid
simultaneous cutting and stirring. Id. The district court
also recognized the ’504 patent has a passage specific to
cheese production that mentions only co-rotation. Id.
     To fill these voids, CSI points out that both the ’559
and ’504 patents refer to cutting and stirring as sequen-
tial, not simultaneous. CSI also notes that Mr. Jay testi-
fied that persons of ordinary skill in the art knew that
cutting and stirring at the same time would damage the
coagulum.
    Of course, the primary difficulty with much of this
testimony is that it arises years after the ’347 invention at
22                CHEESE SYSTEMS, INC.   v. TETRA PAK CHEESE
a time of litigation-driven influences. Moreover, this
after-the-fact testimony ignores the state of the prior art,
including the sketchy nature of Mr. Jay’s own patents.
The district court thus correctly noted that the only
suggestion to reorient the panels is in the ’347 patent.
Slip Op. at 51. And a complete view of the record con-
firms the district court’s conclusion of nonobviousness
over the three Jay patents.
     CSI also contends that the Austrian Patent No. 384
523 B (the AT ’523 patent) renders the asserted claims of
the ’347 patent obvious in light of the Jay ’559 patent.
Appellants’ Br. 59. Analyzing this argument requires the
court to first decide whether the district court abused its
discretion when it struck portions of an expert declaration
offered by CSI from Mr. Jay to oppose Tetra Pak’s motion
for summary judgment. See Slip Op. at 45.
    Mr. Jay’s initial report for CSI contained a single par-
agraph addressing invalidity. Before his deposition, his
discussion of the AT ’523 patent was based solely upon
drawings, since the AT ’523 patent is in German and he
did not obtain a translation. His opinion was based upon
his interpretation of a figure from the AT ’523 with no
understanding beyond the figure. See Appellants’ Br. 60.
    After his deposition, two months beyond the discovery
deadline, and even after Tetra Pak had filed its motion for
summary judgment on this defense, CSI filed a supple-
mental expert declaration from Mr. Jay. His supple-
mental report added another two pages of material based
on a partial translation of the AT ’523 patent. Slip Op. at
2–3.
    Tetra Pak moved to strike Mr. Jay’s supplemental re-
port in its entirety. The district court granted in part
Tetra Pak’s motion. The district court considered the
declaration (a) to the extent the opinions “rely on legal or
common sense arguments that [CSI] has made in its
brief;” and (b) with respect to certain details that, the
CHEESE SYSTEMS, INC.   v. TETRA PAK CHEESE                23
court found, were adequately disclosed prior to the dead-
line but which simply provided greater detail. Id. at 4.
The court found CSI “offers no excuse for its untimely
disclosures, and its arguments that they are not prejudi-
cial are unconvincing.” Id. at 3.
     This court holds that the district court did not abuse
its discretion. Given that Tetra Pak had already deposed
Mr. Jay, that the discovery deadline had long passed, and
that Tetra Pak had already filed its own motion for sum-
mary judgment, the record shows apparent prejudice in
permitting supplementation of the Jay deposition. More-
over, this decision lies well within the district court’s
discretion. See Musser, 356 F.3d at 755 (explaining that
no abuse of discretion arises so long as district court chose
a reasonable option). The trial court’s care in administer-
ing its discretion is shown further by its thoughtful deci-
sion to permit some of the supplemental declaration to
enter the record. See David v. Caterpillar, Inc. 324 F.3d
851 (7th Cir. 2004) (recognizing that a thoughtful analysis
is one indicator of a lack of abuse of discretion). Thus,
this court does not consider the excluded material on
appeal.
    With respect to the merits, the AT ’523 patent is an
Austrian German language prior art patent issued in
1987 that was not considered during original prosecution.
It describes a vertical cheese vat with a curved plate or
valve affixed to the agitator panels on a hinge, and im-
provement on a similar hinged, flat plate:
24                 CHEESE SYSTEMS, INC.   v. TETRA PAK CHEESE




AT ’523 patent Figure 2. See Op. at 44.
     Mr. Jay did not speak German. He thus relied upon
this figure, which the district court aptly described as “not
self-explanatory.” Slip Op. at 44. With only this as the
evidence for his opinion, Mr. Jay opined that the AT ’523
patent disclosed counter-rotation of agitator panels in
vertical cheese vats, with only cutting or stirring edges
moving through the common volume. See Appellants’ Br.
60, 63. However, the AT ’523 patent describes co-rotation.
J.A. 1049; see Slip Op. at 46. Nonetheless, the district
court correctly observed that the patent “never states that
the panels rotate in opposite directions or that they are
mounted facing opposite rotational directions,” but that if
anything, the translation indicated they co-rotated. Slip
Op. at 46.
    This evidence hardly presents a clear and convincing
case of non-obviousness. Further, the translated text
combined with the figure is, at best, ambiguous as to
whether the patent describes counter-rotation. Accord-
ingly, the court affirms the district court’s grants of
summary judgment to Tetra Pak on nonobviousness.
CHEESE SYSTEMS, INC.   v. TETRA PAK CHEESE       25
                              V.
   This court finds the remainder of CSI’s arguments
unpersuasive. Accordingly, this court affirms.
                        AFFIRMED
