       NOTE: This disposition is nonprecedential.


  United States Court of Appeals
      for the Federal Circuit
                ______________________

 FLEXITEEK AMERICAS, INC., a Florida corpora-
 tion, FLEXITEEK INTERNATIONAL AS, a foreign
                  corporation,
               Plaintiffs-Appellants

                           v.

      PLASTEAK, INC., an Ohio corporation,
      PLASDECK, INC., an Ohio corporation,
             Defendants-Appellees
            ______________________

                      2014-1214
                ______________________

   Appeal from the United States District Court for the
Southern District of Florida in No. 0:12-cv-60215-PAS,
Judge Patricia A. Seitz.
                 ______________________

               Decided: March 19, 2015
               ______________________

    SCOTT D. SMILEY, The Concept Law Group. P.A., Fort
Lauderdale, FL, argued for plaintiffs-appellants. Also
represented by MARK C. JOHNSON; MICHAEL I. SANTUCCI,
Santucci, Priore, & Long, LLP, Fort Lauderdale, FL.
2                 FLEXITEEK AMERICAS, INC.   v. PLASTEAK, INC.



   RONALD S. KOPP, Roetzel & Andress, Akron, OH, ar-
gued for defendants-appellees. Also represented by VIJAY
GIBRAN BRIJBASI, Ft. Lauderdale, FL.
                ______________________

Before PROST, Chief Judge, BRYSON and WALLACH, Circuit
                        Judges.
PROST, Chief Judge.
    Flexiteek Americas, Inc. and Flexiteek International
AS appeal from the United States District Court for the
Southern District of Florida’s claim construction of “longi-
tudinal slots” and summary judgment of non-
infringement regarding United States Patent 6,895,881
(’881 patent). For the reasons stated below, we affirm.
                       BACKGROUND
    Appellants are the owners of the ’881 patent, entitled
“shape conforming surface covering.” The invention at
issue in this case is extruded plastic planks that may be
used in covering floors, walls, yacht decks, etc. The
plastic planks are more durable and require much less
upkeep than the traditional exotic woods used for the
aforementioned purposes. Furthermore, the planks are
inherently flexible. The ’881 patent describes the inven-
tion as follows:
    A shape conforming surface covering useful for
    covering any type of surfaces, and comprising
    planks or sheet of a plastic or flexible material
    adapted to be interconnected aside of each other
    thereby forming an assembled surface covering of
    optional length and width, and which planks or
    sheet are of a material that can be brought to
    curved formations, and which at the upper surface
    of the covering is roughened, for instance sanded
    or filed so as to imitate any unique grain effect of
    wooden material. Preferably the planks or sheet
FLEXITEEK AMERICAS, INC.   v. PLASTEAK, INC.                3



    are formed with connection means at the longitu-
    dinal edges thereof. The surface covering may be
    an assembled unit comprising planks and caulk-
    ing elements between each pair of planks.
    ’881 patent abstract. While claim 1 was cancelled on
reexamination it remains in play as claims added during
the reexamination depend from it. Therefore, it along
with claim 2, are representative. Claim 1 reads:
    A shape conforming surface covering useful for
    covering any type of surfaces, characterized in
    that the surface covering comprises planks or
    sheet of a flexible material adapted to be inter-
    connected aside of each other thereby forming an
    assembled surface covering of optional length and
    width, and which planks are of a material that
    can be laid in curved formations, and which at the
    upper surface of the covering is roughened so as to
    imitate any unique grain effect of wooden materi-
    al, further characterized in that the planks or
    sheet are formed with longitudinal slots at the
    underside thereof for facilitating forming of
    curved coverings and for acting as a base for a
    glue or adhesive material by means of which the
    surface covering is mounted on a surface recipi-
    ent.
    Claim 2 reads:
    The shape conforming surface covering of claim 1,
    wherein the planks or sheet are mounted on the
    surface recipient in a tightly curved formation on-
    ly with adhesive and without use of additional
    fasteners.
    In the initial suit (“Flexiteek I”), Appellants obtained a
jury verdict of patent infringement of claim 1 of the ’881
patent against Defendants-Appellees Plasteak, Inc. and
Plasdeck, Inc. Appellees appealed and the Federal Cir-
4                 FLEXITEEK AMERICAS, INC.   v. PLASTEAK, INC.



cuit affirmed. Following the appeal, Appellees petitioned
the U.S. Patent and Trademark Office (“USPTO”) for an
ex parte reexamination. The USPTO granted the petition,
and ultimately invalidated claim 1 of the ’881 patent and
issued a reexamination certificate with new claims 2-29.
Notably, claims 2 through 8 continue to depend on invali-
dated claim 1. Appellees then petitioned the district court
for relief from the Final Judgment as it was based on now
cancelled claim 1, the district court granted the requested
relief.
     Appellants then filed a second suit against the same
defendants alleging, in relevant part, infringement of the
reissued ’881 patent. During the course of litigation, the
parties filed individual Markman briefs. The district
court subsequently struck the parties’ Markman briefs
and ordered the parties to submit a joint claim construc-
tion brief. The district court additionally ordered a tech-
nology tutorial. Although the Appellants objected, the
court ordered that the Appellants’ commercial products
and Appellees’ accused products be presented at the
tutorial. Following the tutorial, the district court asked
the parties if they wanted a Markman hearing. Both
parties informed the district court that they did not.
Following additional briefing, the district court issued its
claim construction order. Appellees then moved for
summary judgment of non-infringement, which the dis-
trict court granted. 1 The Appellants now appeal both the
district court’s claim construction and summary judgment
ruling. We have jurisdiction of this appeal under 28
U.S.C. § 1295(a).




    1 Other claims were also addressed in the summary
judgment, but they are not relevant here.
FLEXITEEK AMERICAS, INC.   v. PLASTEAK, INC.              5



                       DISCUSSION
    While the ultimate construction of a claim term is a
legal question reviewed de novo, underlying factual
determinations made by the district court are reviewed
for clear error. Teva Pharm. USA, Inc. v. Sandoz, Inc.,
135 S. Ct. 831, 842 (2015). Specifically, “when the district
court reviews only evidence intrinsic to the patent (the
patent claims and specifications, along with the patent’s
prosecution history), the judge’s determination will
amount solely to a determination of law, and the Court of
Appeals will review that construction de novo.” Id. at
841. However, when the district court looks beyond the
intrinsic evidence and consults extrinsic evidence, for
example to understand the relevant science, these subsid-
iary fact findings are reviewed for clear error. Id.
    The challenge here goes to the district court’s con-
struction of the term “longitudinal slots.” The district
court construed the term “longitudinal slots” as:
   Grooves spaced relatively close together that run
   parallel to each other for the length of the planks
   or sheet, wherein the grooves have a depth and
   width of a material percentage of the planks’ or
   sheets’ thickness such that the grooves materially
   increase the ability to curve and the surface area
   for adhesion.
Flexiteek Americas, Inc. v. PlasTEAK, Inc., 2013 WL
3762290, at *4 (S.D. Fla. July 16, 2013). The district
court analyzed the relevant claim term in two parts, “slot
spacing” and “depth and width.” Pertaining to “slot
spacing,” the district court determined that the specifica-
tion showed that the slots must run parallel to each other,
be spaced relatively close together, and be equally spaced.
Furthermore, the district court concluded, on the basis of
expert declarations, that one skilled in the art “would
understand that to achieve tight curving with only the use
of glue or adhesive, the primary advancement of the
6                 FLEXITEEK AMERICAS, INC.   v. PLASTEAK, INC.



invention, the longitudinal slots should run parallel to
each other and be spaced in a close-together pattern.” Id.,
at *2.
    The district court additionally analyzed “longitudinal
slots” in reference to their “depth and width.” The district
court found that the invention was an enhancement of the
normal extrusion process. The normal extrusion process
aligns the plank’s molecules in the direction of extrusion,
which results in an extra degree of flexibility as compared
to the inherent flexibility of the material itself. The
district court then found that the invention attempted to
mimic these molecular arrangements by making addi-
tional slots on the bottom of the planks, thereby increas-
ing the flexibility beyond what is possible by the extrusion
process alone. Thus, the district court found that “charac-
terizations of depth and width should be included in the
construction of ‘longitudinal slots’” as it is necessary for
the term’s construction to embody the “essence of the
invention.” Id., at *3, *4.
    Appellants present four main arguments regarding
why the district court’s claim construction is wrong.
First, they argue that the district court’s claim construc-
tion was poisoned by the use of samples of the Appellants’
and Appellees’ commercial embodiments during the
technology tutorial. Second, they contend that the district
court construed the claim term contrary to the intrinsic
evidence. Third, they argue that the district court con-
strued the claim term contrary to three USPTO Examin-
ers during a reexamination proceeding. Fourth, and
finally, they argue that the district court construed the
term contrary to the broader definition given by the
district court in Flexiteek I. We reject all of these argu-
ments.
    District courts are free to conduct technology tutorials
when the district court determines that the tutorial will
aid the court. Furthermore, there is no per se rule that
FLEXITEEK AMERICAS, INC.   v. PLASTEAK, INC.                7



district courts cannot order a party to bring commercial
embodiments to the tutorial to aid the court in under-
standing the technology at issue. Additionally, Appel-
lants’ argument that the court was biased by the
technology tutorial is without merit. Not only does the
district court’s Markman opinion not reference the tech-
nology tutorial or the commercial embodiments, but a
technology tutorial is not a Markman hearing. This is
especially true here, where Appellants were asked by the
court if they wished to have a Markman hearing following
the technology tutorial, and the Appellants declined the
offer.
     We conclude that the district court properly construed
the term “longitudinal slots” in light of both the intrinsic
and extrinsic evidence. The patent’s specification pro-
vides two illustrations of the longitudinal slots, figures 1
and 6. In both of these figures the longitudinal slots are
depicted as being evenly spaced and running the length of
the material. There is no other reference in the patent
specification that provides an alternative definition or
illustration of the longitudinal slots. Furthermore, while
the figures do not specify exact depth ranges for the
longitudinal slots, they do show that the slots have a non-
insignificant depth.
    Additionally, during the reexamination Dr. C.K. Rhee,
Flexiteek’s expert, asserted that the use of longitudinal
slots on the underside of the material represented the
true invention of the patent. In reaching this conclusion
Dr. Rhee acknowledged that the extrusion process itself
made the material inherently more flexible. Thus, he
stated that the longitudinal slots added an extra degree of
flexibility along the axis of extrusion, which was greater
than the material’s inherent flexibility. Dr. Rhee also
stated that the inventor, “greatly enhanced the degree of
flexibility that would have been inherent to the material
itself by adding a series of longitudinal slots and/or ribs in
a very tight pattern on the underside of the plank or
FLEXITEEK AMERICAS, INC.   v. PLASTEAK, INC.              9



be no infringement as “longitudinal slots” inherently
require at least two recesses. We agree. The claim con-
struction of “longitudinal slots” requires that a plank have
“grooves,” i.e. more than one groove. As the Shiplap
design has no more than a single groove, it does not meet
the “longitudinal slots” claim limitation, and thus sum-
mary judgment for the Appellees is warranted.
    Turning to the T-Shaped design, the district court
found that even if the edges were found to be slots, the
side edges do not constitute slots as defined by the patent
claims as they are not relatively close together. In reach-
ing its decision, the district court relied on Dr. Rhee’s
expert report, submitted during the reexamination, that
confirmed that the longitudinal slots taught by the ’881
patent are found on the underside of the individual
planks of the flooring material and thus materially in-
crease the ability of the planks to curve. Again we agree
with the district court’s analysis. The T-Shape design has
at most two grooves on opposite sides of the plank. The
claim limitation “longitudinal slots” require that the
grooves be spaced relatively close together; it is axiomatic
that grooves on opposite sides of a plank could not meet
the claim limitation requiring that the grooves be “rela-
tively close together.” Furthermore, the Appellants own
expert explains that in order to increase the flexibility of
the planks, it is necessary that the longitudinal slots be
positioned in a very tight pattern. J.A. 789. Again,
having slots on either side of a plank is not consistent
with being in a “very tight pattern.” Therefore we affirm
the district court’s grant of summary judgment as it
relates to the T-Shape products.
   We have reviewed Appellants’ remaining arguments
and find them unpersuasive.
                       CONCLUSION
    For the reasons stated above, we affirm the judgment
of the District Court for the Southern District of Florida
10              FLEXITEEK AMERICAS, INC.   v. PLASTEAK, INC.



as it pertains to the claim construction of the phrase
“longitudinal slots” and the district court’s summary
judgment ruling as it pertains to non-infringement.
                    AFFIRMED
