Court Opinion

ID: 2673313
Source: CourtListenerOpinion
Date Created: 2014-05-10 03:13:42.403438+00
Date Added: 2024-06-11T13:06:47.795231
License: Public Domain

In the United States Court of Federal Claims
                                            No. 96-166 C
                                      (Filed: March 31, 2014)

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                                           *
    ZOLTEK CORPORATION,                    *
                                           *
                      Plaintiff,           *
          v.                               *
                                           *
    THE UNITED STATES,                     *
                                           *
                      Defendant.           *
                                           *
    ***************************************
                                     OPINION AND ORDER

        This matter is before the Court following a three-day trial on the issue of validity of
United States Patent Reissue No. 34,162 (the “‘162 Patent”).1 During trial, the Government
presented evidence which, it contends, renders the ‘162 Patent invalid under three distinct legal
theories: the patent does not cover patent-eligible subject matter under 35 U.S.C. § 101, the
patent is obvious under 35 U.S.C. § 103, and the patent lacks adequate written description under
35 U.S.C. § 112, ¶ 1.

         As explained below, the Court is not persuaded by the Government’s subject matter
argument under 35 U.S.C. § 101. The Court is, however, convinced that claims 1-22 and 33-38
(all of the claims asserted in this matter) are invalid both for obviousness under 35 U.S.C. § 103
and written description under § 112. The Court therefore directs entry of judgment in favor of
the Government.

         I.    Background

        For purposes of this background, the Court will present only a very broad background of
the case—both factually and procedurally. Because the Government has presented three distinct

1
  The ‘162 Patent appears in the trial record as Joint Exhibit 1. For purposes of clarity, because
the ‘162 Patent is referenced often in this opinion, the Court will refer to the ‘162 Patent directly.
When referencing other exhibits, the Court will generally use the following short-hand: JX
means Joint Exhibit Number X, PY means Plaintiff’s Exhibit Number Y, and DZ means
Defendant’s Exhibit Number Z.
challenges to the validity of the ‘162 Patent, the Court will introduce the more detailed facts
relevant to each legal theory in its discussion of those theories.

               a. Factual Background

       Plaintiff, Zoltek Corporation (“Zoltek”), brought this patent suit on March 25, 1996. The
case concerns the Government’s alleged infringement, by and through the Department of the Air
Force, of the ‘162 Patent, which Zoltek owns. The factual background of this matter is set forth
in numerous prior opinions. See, e.g., Zoltek Corp. v. United States, 86 Fed.Cl. 738, 739-42
(2009); 85 Fed.Cl. 409, 411 (2009); 71 Fed.Cl. 160, 161-64 (2006); 61 Fed.Cl. 12, 14-15 (2004);
58 Fed.Cl. 688, 689-91 (2003); 51 Fed.Cl. 829, 830-32 (2002); 48 Fed.Cl. 290, 292 (2000).
These factual underpinnings are, of course, heavily supplemented by the facts derived from trial.
As the case now stands, Zoltek alleges that the United States has infringed the ‘162 Patent
through its development and production of the B-2 Bomber and the F-22 Raptor.

       The ‘162 Patent is a reissue of United States Patent No. 4,728,395 (the “‘395 Patent”).
Joint Exhibit (“J”) 1.1. The ‘395 Patent was issued on March 1, 1988 from an application filed
by George Boyd on October 12, 1984. At the time of filing, Mr. Boyd was employed by
Stackpole Fibers Co., Inc. Stackpole was the original assignee of the ‘395 Patent, but Zoltek
acquired Stackpole in 1988 and subsequently took assignment of the ‘162 Patent.

        It suffices here to say that the ‘162 Patent describes a process for manufacturing carbon
fiber sheet products with controlled surface electrical resistivity. Zoltek Corp. v. United States,
48 Fed.Cl. 290, 292 (2000). Claim 1 is representative:

                    A method of manufacturing a plurality of different value controlled
           resistivity carbon fiber sheet products employing a carbonizable starting
           material; said method comprising [oxidizing and stabilizing the
           carbonizable fiber starting material at an elevated temperature of the order
           of 220 degrees Centigrade to effect aromatic rearrangement of the fibers,]
           selectively partially carbonizing [the] previously oxidized and stabilized
           fiber starting material for a predetermined period in an oxygen free
           atmosphere within a furnace at [a] selected temperature values within a
           temperature range from 370 degrees Centigrade to about 1300 degree
           Centigrade by soaking the stabilized fiber starting material at the selected
           temperature for the predetermined period of time to provide a [desired]
           preselected known volume electrical resistivity to the partially carbonized
           fibers corresponding to that volume electrical resistivity value required to
           provide the preselected desired surface resistance value for the finished
           sheet products, and thereafter processing the partially carbonized fibers
           into [desired electrical resistivity] homogeneous carbon fiber sheet
           products [having the form of non-woven paper or woven or knitted fabric
           sheet products] having the preselected desired surface electrical
           [resistivities] resistances.

                                                  2
‘162 Patent at 8:42-66.2

         By way of this process, a manufacturer can determine the level of surface resistivity
necessary for a particular application, and then create carbon fibers with that preselected level of
resistivity by partially carbonizing a fiber starting material for a certain period of time at a given
temperature between 370 and 1300 degrees Centigrade. 48 Fed.Cl. at 293. The fibers are then
incorporated into a sheet product which takes on the resistive properties of the constituent fibers.
Id. at 296. As this Court noted in its claim construction decision, “[t]he essence of the invention
is the relation between the partial carbonization of the single carbon fiber and the electrical
resistivity of the sheet product which incorporates the partially carbonized single fibers.” Id.
Zoltek alleges that the processes used by or for the Government to produce silicon carbide fiber
mats and preimpregnated materials incorporated into the F-22 and B-2 infringes the ‘162 Patent.

        Specifically, Zoltek asserts claims 1-22 and 33-38 of the ‘162 Patent in this action. See
Joint Stipulation of Fact, Witnesses and Exhibits (“Jt. Stip.”) at ¶ 2. Of these, claims 1, 11, 15
and 33 are independent claims. See ‘162 Patent at 8:42, 9:65, 10:35, 11:47. The rest of the
asserted claims depend upon these claims. See generally ‘162 Patent at 8:67-11:34.

               b. Procedural History

        As one might expect of a case approaching its third decade of proceedings, the procedural
background of this matter is extensive. The Court will discuss only a few particularly relevant
points in this background in order to explain the posture at trial.

         In 2006, the Federal Circuit heard this case on appeal. See Zoltek Corp. v. United States,
442 F.3d 1345 (Fed. Cir. 2006). The result of its decision was the dismissal of the F-22 portion
of the case. The B-2 portion of the case proceeded uninterrupted. However, on March 14, 2012,
the Federal Circuit published another opinion in this case. See Zoltek Corp. v. United States, 672
F.3d 1309 (Fed. Cir. 2012). In that decision, the Federal Circuit, acting sua sponte and sitting en
banc for this part of its decision only, vacated its 2006 decision in its entirety. Id. at 1317. The
result of this decision was that Zoltek’s F-22 case was resurrected almost six years to the day
after it was left for dead in this Court. The Court ordered the parties to submit a Joint Status
Report addressing the practical implications of the Federal Circuit’s 2012 decision.

       In their Joint Status Report, the parties disagreed over how to proceed. Zoltek wanted to
complete discovery relating to the F-22 before trial, such that both the B-2 and the F-22 issues
could be resolved simultaneously. See Joint Status Report, Docket No. 456, at 1-2. The
Government believed that the Court should schedule trial on the B-2 immediately since there
were no common issues between the two sets of claims. Id. at 2.

2
  Note that the bracketed language is part of the original patent which was removed during
reissue proceedings and the italicized language is language which was added during reissue
proceedings. See ‘162 Patent at 1:5-8 (“Matter enclosed in heavy brackets [ ] appears in the
original patent but forms no part of this reissue specification; matter printed in italics indicates
the additions made by reissue.”).
                                                  3
         On February 15, 2013, the parties submitted another status report. The parties still
disagreed as to the time and form of trial, so the Court ordered the parties to submit briefs in
support of their positions. The Court’s order required the parties to address specific questions,
the answers to which it would consider in resolving the trial scheduling conflict. See generally
Docket No. 472. After considering the parties’ positions, the Court determined that the most
efficient process moving forward would be to hold trial to address the Government’s assertions
of invalidity first, and to return to the remaining questions afterwards, if necessary. That order
led to the trial which is the subject of the instant opinion.

               c. The Trial

         The Court presided over the trial in this matter beginning on November 4, 2013. During
the trial, the Court heard testimony from the Government’s expert, Dr. Brian Sullivan, and from
Zoltek’s CEO, Zsolt Rumy, who testified both as a fact and expert witness. The Court also
received, by way of deposition testimony, evidence from a number of other witnesses who are
either deceased, advanced in age, or who otherwise were unable to appear live at trial. Although
this opinion takes all of the admitted evidence into account, the parties’ briefs make clear that Dr.
Sullivan and Mr. Rumy are the key witnesses in this case.

       II.     The Government’s Invalidity Contentions

        As stated above, the Government has challenged the validity of the ‘162 Patent under
three separate grounds. First, it argues that the ‘162 Patent claims subject matter which is
ineligible for patent protection under 35 U.S.C. § 101 and Supreme Court precedent. It also
argues that the ‘162 Patent is invalid for obviousness under 35 U.S.C. § 103. Finally, it argues
that the ‘162 Patent is invalid under 35 U.S.C. § 112, ¶ 1, for a lack of written description. The
Court will address each of these arguments in turn.

       III.    The ‘162 Patent Is Not Invalid Under 35 U.S.C. § 101

       The Government has asked the Court to wade into the morass that is § 101 of the Patent
Act. In doing so, the Government argues that Claims 1-4, 9, 10 and 33-38 of the ‘162 Patent, all
of which are method claims, are invalid. Unfortunately for the Government and the Court, this
expedition proves fruitless as the Government has not convinced the Court that Zoltek’s patent
claims patent-ineligible subject matter.

        “Patent eligibility under § 101 presents an issue of law,” though the “legal conclusion
may contain underlying factual issues.” Accenture Global Servs. V. Guidewire Software, Inc.,
728 F.3d 1336, 1340-41 (Fed. Cir. 2013). Invalidity by way of a failure to claim patent-eligible
subject matter must be proven by clear and convincing evidence. Ultramercial, Inc. v. Hulu,
LLC, 722 F.3d 1335, 1338-39 (Fed. Cir. 2013).

         Section 101 of the Patent Act states that, “[w]hoever invents or discovers any new and
useful process, machine, manufacture, or composition of matter, or any new and useful
improvement thereof, may obtain a patent therefor, subject to the conditions and requirements of
this title.” 35 U.S.C. § 101. The plain language of this statute belies the complexity of the

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subject matter analysis which the Supreme Court has devised through a series of cases dating
back to the 1970s. It is now well-established that, even if they fall squarely within the expressly-
stated subjects of § 101, “laws of nature, physical phenomena, and abstract ideas” are not patent
eligible. Diamond v. Chakrabarty, 447 U.S. 330, 309 (1980) (citing Parker v. Flook, 437 U.S.
584 (1978); Gottschalk v. Benson, 409 U.S. 63, 67 (1972)). In order to be patent eligible, “a
process that focuses upon the use of a natural law [must] also contain other elements or a
combination of elements, sometimes referred to as an ‘inventive concept,’ sufficient to ensure
that the patent in practice amounts to significantly more than a patent upon the natural law
itself.” Mayo Collaborative Services v. Prometheus Laboratories, Inc., 132 S. Ct. 1289, 1294
(2012).

        The Government argues that the claims are invalid because they embody nothing more
than a law of nature. For example, the Government points to Figure 4 of the patent to support its
contention. It argues that Figure 4, which charts a relationship between heat treatment
temperature and surface resistance, see ‘162 Patent Fig. 4, demonstrates the ineligibility of the
‘162 Patent claims by showing that the claims embody nothing more than a natural law that links
temperature to resistance. Relying upon the testimony of its expert, Dr. Brian Sullivan, the
Government argues that the independent claims at issue (claims 1 and 33) consist of three parts:
(1) the manufacture of carbon fibers using conventional carbonization equipment and techniques;
(2) the manufacture of a sheet product using conventional techniques and processes; and (3) “the
concept that if you control the fibers’ volume electrical resistivity it gives you the ability to
control the sheet or surface resistivity of the final carbon mat product.” Gov’t Br. at 10 (quoting
Tr. 163-64). The Government argues that these three parts render the ‘162 Patent’s claims
similar to those found ineligible in Flook and Mayo.

        Zoltek counters by relying on Diamond v. Diehr, 450 U.S. 175 (1981), a case in which
the Supreme Court affirmed the validity of the claims before it. Zoltek argues that the ‘162
Patent looks much more like Diehr than any other Supreme Court decision. As such, it claims
that the ‘162 Patent is eligible for patent protection and therefore not invalid under § 101.

        The Court agrees with Zoltek. The Government’s comparisons to the ineligible claims in
Flook and Mayo are much less apt than comparison to Diehr. The patent application in Flook
described a method of updating alarm limits. As the Government observes, the method consisted
of three steps: (1) measuring a process variable; (2) employing an algorithm to solve a
mathematical formula for an alarm limit value; and (3) updating the alarm limit accordingly.
Flook, 437 U.S. at 585. In essence, Flook amounted to a claim for a mathematical equation and
some insignificant “‘post-solution’ activity”: updating an alarm limit. See id. at 590.

         Likewise, in Mayo, the patent consisted of three steps: (1) an “administering” step; (2) a
“determining” step; and (3) a “wherein” step. Mayo, 132 S. Ct. at 1297. Mayo actually looks a
lot like Flook, in that two steps involved something of a calculation (the “administering” and
“determining” steps) and the third step added nothing of substance. See id. (“[T]he ‘wherein’
clauses simply tell a doctor about the relevant natural laws, at most adding a suggestion that he
should take those laws into account when treating his patient. That is to say, these clauses tell
the relevant audience about the laws while trusting them to use those laws appropriately where
they are relevant to their decisionmaking.”) (emphasis added). In essence, the “wherein” clause

                                                 5
in Mayo mirrors Flook’s third element embodying insignificant post-solution activity. Neither
case addressed claims that actually resulted in a functional product.

         These cases lie in stark contrast to the claims of the patent application in Diehr. In that
case, the claims covered a process for curing rubber by monitoring the internal temperature of
the rubber mold. Diehr, 450 U.S. at 177. The applicants characterized their contribution as the
ability to improve rubber cure quality by constantly monitoring the temperature of the mold and
updating cure time via a well-known equation (the Arrhenius equation). Id. at 178-79. Even
though the claims revolved around the application of an equation, just as the claims in Flook, the
Court found the claims eligible for patent protection because they “involve the transformation of
an article … into a different state or thing.” Id. at 184. In other words, the post-solution activity
was not insignificant.

        So too here, the result of the claims is a not insignificant physical change. While the
claims may be directed in part to what can be reasonably characterized as a mathematical
relationship (as between heat treatment temperature and surface resistance), they do something
significant beyond state a law of nature: they direct application of that law to produce controlled
surface resistivity carbon fiber sheet products. As such, the Court finds that the challenged
claims of the ‘162 Patent cover patent eligible subject matter.

        IV.     Claims 1-22 and 33-38 of the ‘162 Patent Are Invalid Under § 103

       The Court turns next to the Government’s argument that the ‘162 Patent is invalid as
obvious under 35 U.S.C. § 103. The Court first reviews the claimed invention and prior art
references relevant to the parties’ arguments.

                a. The Claimed Invention

        The ‘162 Patent discloses methods for manufacturing controlled surface resistance carbon
fiber sheet products. As this Court has previously stated: “The essence of the invention is the
relation between the partial carbonization of the single carbon fiber and the electrical resistivity
of the sheet product which incorporates the partially carbonized single fibers.” Zoltek Corp. v.
United States, 48 Fed.Cl. 290, 296 (2000). The Government argues that claims 1 through 22 and
33 through 38, all of the claims still asserted by Zoltek in this case, are invalid as obvious.

        Two figures from the ‘162 Patent are particularly relevant to the Government’s theory.
The first, Fig. 3 of the ‘162 Patent, is a plot of electrical resistivity of a single carbon fiber as a
function of heat treatment temperature. The second, Fig. 4, plots both the resistivity of the
carbon fiber and the surface resistance of a sheet product made in accord with the patented
method as functions of heat treatment temperature. Both Figures demonstrate a decrease in
resistivity/resistance as heat treatment temperature increases.

                b. Prior Art References

       To qualify as prior art for the obviousness analysis, “a reference must qualify as
‘analogous art,’ i.e., it must satisfy one of the following conditions: (1) the reference must be

                                                    6
from the same field of endeavor; or (2) the reference must be reasonably pertinent to the problem
with which the inventor is involved.” K-TEC, Inc. v. Vita-Mix Corp., 696 F.3d 1364, 1375 (Fed.
Cir. 2012). “A reference is reasonably pertinent if it, as a result of its subject matter, ‘logically
would have commended itself to an inventor’s attention in considering his problem.” Id.
(quoting Innovention Toys, LLC v. MGA Entm’t Inc., 637 F.3d 1314, 1321 (Fed. Cir. 2011)).
Whether a prior art reference is “analogous” is a question of fact. Wyers v. Master Lock Co., 616
F.3d 1231, 1237 (Fed. Cir. 2010).

        In arguing that the ‘162 Patent is obvious, the Government relies upon a series of prior art
references. Zoltek challenges the Government’s reliance upon several of these references based
on a few different theories. Before turning to Zoltek’s arguments, the Court briefly summarizes
the references3 upon which the Government relies in its post-trial brief:

       (1) Shindo (J101): The Shindo Report (“Shindo”) comprises a research report published
           in December of 1961. It discusses the manufacture and use of carbon fibers using
           polyacrylonitrile as a starting material. Tr. at 75-76. Dr. Sullivan testified at trial that
           Shindo disclosed the same relationship that is shown in Fig. 3 of the ‘162 Patent, i.e.,
           that increasing heat treatment temperatures results in decreased volume resistivity (or
           increased conductivity) of the carbon fibers. See J101.40; Tr. 76-77. Shindo also
           discloses that other material properties, like Young’s Modulus, which likewise
           change based on a fiber’s heat treatment temperature. J101.28. Dr. Sullivan
           explained at trial that these changes in material properties—Young’s Modulus and
           volume resistivity—are the result of the predictable increase in crystallinity in the
           system. See Tr. at 78 (“This is, for my purposes, one of the most important graphs in
           this report, because it explains why all these other properties are changing with heat
           treatment temperature, simply because the graphite crystallites themselves are
           growing and becoming more well ordered.”) (discussing the graph on J101.33).

       (2) Kitago (J111): The Kitago reference is United States Patent No. 3,998,689, which
           issued on December 21, 1976. Kitago discloses a process for producing carbon fiber
           paper. The disclosed process uses short carbon fibers combined with other
           ingredients to form a slurry, which is then treated at a predetermined heat temperature
           to form a final conductive paper product. See J111.3-111.4; Jt. Stip. ¶¶ 56-58.
           According to Dr. Sullivan, “this patent is relative [sic] in that a very similar process
           was used here to create the carbon fiber sheet product, as [is used in the ‘162 Patent].
           Differences are that the Zoltek paper used chopped fiber filaments that had already
           been heat-treated and carbonized at high temperatures, whereas the Kitago and
           Yoshida patent performed the heat treatment on the carbon fiber paper subsequent to
           its formation.” Tr. at 80. Dr. Sullivan highlighted a table in Kitago which contains
           data for certain physical properties of the sheet product produced via the patented
           method at two different heat treatment temperatures: 1000°C and 2000°C. Tr. at 80-

3
  For ease of reference, the Court refers to the prior art references by the author’s name or
authors’ names. In effect, the Court adopts the nomenclature used by the parties throughout this
litigation, rather than the exhibit numbers used for trial purposes.
                                                  7
           81 (referencing J111.5). The table shows a significantly lower resistance for
           treatment at the higher temperature. See J111.5 Table 4.

       (3) Layden (J109): The Layden reference is United States Patent No. 4,080,413, which
           issued on March 21, 1978. Layden discloses a process for producing an electrically
           conductive carbon fiber sheet product that, according to Dr. Sullivan, is very similar
           to the process disclosed in the ‘162 Patent. Tr. 84 (“The patent is relative – is
           relevant in that a very similar process was used in the Layden patent as was used in
           the [‘162 Patent] to create the carbon sheet product.”). Dr. Sullivan also explained
           that Layden demonstrates that there was a desire to control the resistivity of the
           material by means of different heat treatment temperatures. Tr. 84-85; Jt. Stip. ¶¶ 59-
           64.

       (4) Topchjiev (J4): The Topchjiev reference is a United Kingdom patent published in
           1965. Dr. Sullivan testified that this patent discusses a method of producing carbon
           sheet products from oxidized and stabilized carbon fibers that are subsequently heat-
           treated. Tr. at 86; see also Jt. Stip. ¶¶ 73-75. According to Dr. Sullivan, Topchjiev
           demonstrates a desire to control electrical conductivity of the carbon sheet product.
           Tr. at 86-88. He also explained the simple mathematical relationship between
           conductivity and resistivity. Tr. at 88.

       (5) Fischbach and Komaki (J120): The Fischbach and Komaki reference is an article
           entitled “Electrical Resistance of Carbon Fibers,” which was published in 1979.
           J120.1. Fischbach and Komaki explains the change in resistivity of various precursor
           fibers as heat treatment temperature changes. Tr. 88-92; see also Jt. Stip. ¶¶ 65-66.
           Dr. Sullivan testified that this reference discloses the same trend as in Fig. 3 of the
           ‘162 Patent; specifically, that increasing heat treatment temperature results in a
           decreased volume electrical resistivity of the carbon fibers. Tr. 89. Dr. Sullivan also
           testified that, even though the chart in Fischbach and Komaki was only directed to the
           resistivity of individual carbon fibers, the same relationship would hold true for a
           sheet product made of the fibers and other constituent parts. Tr. 91.

       (6) The Rule of Mixtures: Dr. Sullivan described the “Rule of Mixtures” in his testimony:

                  The rule of mixtures basically states that if you know the relative
               volume fractions of all the constituents that make up a composite and
               you know the property of the individual constituents, you’re able to
               predict what the property of the composite is on the basis of the
               constituents’ fiber volume fractions and individual properties.

           Tr. 113. He explained that a “volume fraction” is the percentage, by volume, of the
           specific material within the composite. Tr. 114-15. Dr. Sullivan referred to five
           different prior art references authored by Hashin4, Rosen and Christensen, each of

4
 The Court notes that the table of joint exhibits provided by the parties misspells the name of the
author, Hashin, as “Hashim.” In its brief, Zoltek likewise repeatedly misspells Hashin’s name.
                                                 8
           which disclosed the use of the Rule of Mixtures to determine composite properties,
           including electrical conduction. See Tr. 115-26 (discussing D49, J8, J10, J9 and J5);
           see also Jt. Stip. ¶ 68; J8 (“Hashin Report”); Jt. Stip. ¶ 69; J10 (“Rosen Article”), Jt.
           Stip. ¶ 70; J9 (“Hashin Survey”), Jt. Stip. ¶ 71; J5 (college textbook by Christensen,
           entitled “Mechanics of Composite Materials” (“Christensen”)); Jt. Stip. ¶ 67.

       (7) Admissions of the patentee, inventor or applicant: The Government also notes that
           “[a]dmissions in the specification regarding the prior art are binding on the patentee
           for purposes of a later inquiry into obviousness.” PharmaStem Therapeutics, Inc. v.
           Viacell, Inc., 491 F.3d 1342, 1362 (Fed. Cir. 2007); see also Smith & Nephew, Inc. v.
           Rea, 721 F.3d 1371, 1380 n.5 (Fed. Cir. 2013) (“Expert opinions that are contrary to
           admissions in the specification do not create a factual issue.”) (citing PharmaStem,
           491 F.3d at 1361-62). Admissions and statements made during prosecution of a
           patent also constitute binding admissions as to the scope of prior art. See Springs
           Window Fashions LP v. Novo Indus., L.P., 323 F.3d 989, 995 (Fed. Cir. 2003) (“The
           public notice function of a patent and its prosecution history requires that a patentee
           be held to what he declares during the prosecution of his patent.”).

           Dr. Sullivan explained that the ‘162 Patent states that conventional paper-making
           equipment could be used to perform the paper making steps as claimed in the ‘162
           Patent. See Tr. 69-70; see also Jt. Stip. ¶ 55. The ‘162 Patent also admits that it was
           known prior to the filing date that volume resistivity of the final fiber decreases as a
           heat treatment temperature increases. See Tr. 72 (referring to ‘162 Patent 5:38-49).

           During prosecution, the applicant stated that the patentably distinguishing feature of
           the disclosed invention was the ability to control the sheet resistivity by carbonizing
           at a selected temperature within the range of 370 degrees to 1250 degrees Centigrade.
           See J3.164; see also J3.142. These admissions were mirrored at trial by Zoltek’s
           CEO, Zsolt Rumy. See Tr. 342 (admitting that methods of making carbon fibers and
           carbon fiber paper products were known in 1984); see also Tr. 343 (admitting that the
           “uniqueness” of the processes sought to be patented rested in the “coordination of the
           heat treatment temperature of a fiber in order to get the … surface resistance … in the
           product.”).

         The Court finds, in light of Dr. Sullivan’s testimony, that all of these references constitute
analogous prior art. To the extent that the references discuss controlling resistivity of carbon
fibers, they are plainly analogous to part of the method described in the ‘162 Patent. The same
can be said for the references discussing the change in resistivity based on heat treatment
temperature. Even the references discussing conductivity, like Shindo and Topchjiev, would be
relevant because, as explained by Dr. Sullivan, a person of ordinary skill in the art would
understand the mathematical relationship between conductivity and resistivity. See Tr. 88.

         Zoltek argues that Topchjiev, Layden and Fischbach and Komaki are not directed to
surface resistivity, and the Court presumes that the unwritten point is that they instead refer to
volume resistivity of the precursor fiber or of the final sheet product. However, as Dr. Sullivan
testified at trial, a person of ordinary skill in the art would understand how to calculate surface

                                                  9
resistivity from sheet volume resistivity: surface resistivity is simply the volume resistivity of the
sheet divided by the sheet thickness. Tr. 107-08. Zoltek offered no evidence to contradict Dr.
Sullivan’s proposed relationship between volume and surface resistivities; as such, the Court
accepts Dr. Sullivan’s testimony as true and accurate. Dr. Sullivan’s testimony convinced the
Court that a person of ordinary skill would understand the relationship between these two values
and, therefore, would not limit his research only to surface resistivity but would also consider
sources that discuss volume resistivity.

        Zoltek’s challenge to Dr. Sullivan’s use of the Rule of Mixtures is a better argument, but
again, Zoltek’s arguments do not give the Court reason to doubt Dr. Sullivan’s application of the
Rule of Mixtures. First, Zoltek argues that the Hashin Report does not discuss carbon fiber
composites or their electrical characteristics. Next, it argues that the Rosen Article is directed to
fully carbonized carbon fibers, not partially carbonized fibers. Finally, Zoltek argues that the
Hashin Survey and Christensen does not mention surface resistivities, partially carbonized fibers,
or controlling surface resistivity of carbon fiber sheet products by way of volume resistivity of
individual carbon fibers.

        Zoltek completely misses the point of Dr. Sullivan’s reliance on these references. They
are not directed to the specifics of carbon fibers or controlling resistivity. Dr. Sullivan applied
these references to explain how, in the field of composite materials, if one knows the relevant
characteristic (i.e., resistivity) of the components and their volume fractions, one can calculate
with reasonable certainty the relevant characteristic of the composite material comprised of those
components. To this end, the Court finds the Rule of Mixtures relevant because, by Zoltek’s
own characterization at trial, the sheet products produced in accord with the ‘162 Patent are
composite materials. See Tr. 21 (Zoltek, in its opening statement, explained that, “[i]n contrast
to Dr. Sullivan, Zsolt Rumy and Lee McKague have a combined more than 80 years of
experience in the actual manufacture of carbon fiber composite products.”) (emphasis added).

        In sum, the Court concludes that all of the references cited by the Government are, at the
very least, analogous art. If a person skilled in the art sought to produce a carbon fiber
composite material with controlled surface resistivity, that person would almost certainly look at
how to control the resistivity of the carbon fiber starting material, how to manufacture a
composite sheet product from the carbon fiber starting material, and how to determine a
composite material’s overall characteristics based on the characteristics of its components.

               c. Obviousness Standards

        A patent is invalid if it is obvious. 35 U.S.C. § 103. Section 103 provides that a patent
may not be obtained “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 to which the claimed invention
pertains.” Id.; see KSR Int’l Co. v. Teleflex, Inc., 550 U.S. 398, 406 (2007). In reaching its
determination, a court must avoid the use of hindsight or “ex post reasoning.” KSR, 550 U.S. at
421; see also Graham v. John Deere Co. of Kan. City, 383 U.S. 1, 36 (1966).

                                                 10
        Obviousness can be demonstrated where modifications to a single prior art reference
would have been obvious, see, e.g., Takeda Chem. Indus., Ltd. V. Alphapharm Pty., Ltd., 492
F.3d 1350, 1357 (Fed. Cir. 2007), or where it would have been obvious to combine multiple
elements of various pieces of prior art. See KSR, 550 U.S. at 417. The mere fact, however, that
prior art could have been modified to achieve the patent-in-suit at the time of the invention does
not render the invention invalid on the grounds of obviousness, “unless the prior art suggests the
desirability of the modification.” Cordis Corp. v. Medtronic Ave, Inc., 511 F.3d 1157, 1172
(Fed. Cir. 2008). “Obviousness is a question of law based on underlying findings of fact.” In re
Kubin, 561 F.3d 1351, 1355 (Fed. Cir. 2009); see also Rolls-Royce, PLC v. United Techs. Corp.,
603 F.3d 1325, 1338 (Fed. Cir. 2010) (“obviousness is a question of law based on underlying
factual inquiries”).

                          i. The Graham Factual Inquiries

        In Graham, the Supreme Court set out the factual inquiries for the determination of
patent invalidity based on obviousness. These inquiries, known as the Graham factors, govern
whether the claimed invention is obvious and, therefore, the patent invalid under § 103. These
factors include (1) the level of ordinary skill in the art; (2) the scope and content of the prior art;
and (3) the differences between the prior art and the claimed invention. KSR, 550 U.S. at 406
(quoting Graham, 383 U.S. at 17-18). Under this framework, “the obviousness or non-
obviousness of the subject matter is determined.” Graham, 383 U.S. at 17.

        Graham also requires consideration of secondary indicia (frequently called
considerations) of non-obviousness, such as “commercial success, long felt but unsolved needs,
[or the] failure or others” to achieve comparable results. Id. at 17-18. Since Graham, courts
have also considered skepticism or disbelief, copying or praise of the claimed invention, and
unexpected results as secondary considerations of non-obviousness. Brown & Williamson
Tobacco Corp. v. Philip Morris, Inc., 229 F.3d 1120, 1129 (Fed. Cir. 2000).

                         ii. Reason to Combine Prior Art References

        When an innovation is alleged to be obvious in light of the combination of two or more
prior art references, “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.” KSR, 550 U.S. at 418. In KSR, the Court held that a patent is invalid if “[t]he
combination of familiar elements according to known methods is likely to be obvious when it
does not more than yield predictable results.” Id. at 416. As the Court noted,

                  Often, it will be necessary for a court to look to interrelated teachings
              of multiple patents; the effects of demands known to the design
              community or present in the marketplace; and the background knowledge
              possessed by a person having ordinary skill in the art, all in order to
              determine whether there was an apparent reason to combine the known
              elements in the fashion claimed by the patent.

Id. at 418.

                                                   11
        The KSR Court also held that a patent may be obvious in light of a combination of prior
art references if the combination was “obvious to try.” Id. at 421. “When there is a design need
or market pressure to solve a problem and there are a finite number of identified, predictable
solutions, a person of ordinary skill has good reason to pursue the known options within his or
her technical grasp.” Id. Whether a solution is predictable is determined in part by whether a
person of ordinary skill in the art would have had a reasonable expectation of success. Life
Techs., Inc. v. Clontech Labs., Inc., 224 F.3d 1320, 1326 (Fed. Cir. 2000) (“Reasonable
expectation of success is assessed from the perspective of the person of ordinary skill in the
art.”).

        Naturally, some fields of technological art are less predictable than others. “[T]o the
extent an art is unpredictable, as the chemical arts often are, KSR’s focus on … ‘identified,
predictable solutions’ may present a difficult hurdle because potential solutions are less likely to
be genuinely predictable.” Procter & Gamble Co. v. Teva Pharmaceuticals USA, Inc., 566 F.3d
989, 996 (Fed. Cir. 2009).

               d. Discussion

       Before turning to the issues disputed by the parties, the Court first discusses the level of
ordinary skill in the art, which is not in dispute. The Court will then discuss the remaining
Graham factors.

                       i. The Level of Ordinary Skill in the Art

       It has been settled since 2000 that the parties agree on the level of ordinary skill in the art.

               The parties agree that one skilled in the art would have at least a
           bachelor’s degree in chemical engineering or chemistry. One skilled in
           the art would also have a working knowledge of the characteristics and
           uses of cellulosic, pitch and acrylic carbon fiber precursors, the
           characteristics of carbon fiber, the pyrolization processes used in making
           carbon fiber and processes for making carbon fiber sheet products.

Zoltek Corp. v. United States, 48 Fed.Cl. 290, 293 n.1 (2000); Jt. Stip. ¶ 135.

                       ii. The Government Has Made Out a Prima Facie Case of
                           Obviousness

        The parties have presented numerous arguments with respect to obviousness. Because
the Government’s theory rests heavily on Dr. Sullivan’s testimony and Zoltek directly challenges
much of Dr. Sullivan’s testimony, the Court first addresses those challenges which cannot
readily be linked to a specific substantive question. It then turns to the parties’ substantive
dispute.

                                                 12
                               1. Zoltek’s Challenges to Dr. Sullivan’s Testimony are
                                  Unpersuasive

        Zoltek first argues that Dr. Sullivan’s educational and work experience did not involve
the production of carbon fibers or carbon fiber sheet products having specified electrical
characteristics. This is essentially a retread of the very same argument the Court rejected in its
summary judgment opinion, which also addressed the parties’ motions to strike the other party’s
expert. Specifically, the Court noted in that opinion that Zoltek argued that Dr. Sullivan was
unqualified to testify in this case “given the absence of any work involving electrical properties
of carbon fibers.” See Zoltek, 95. Fed.Cl. at 685. The Court rejected this theory because, in its
view, it mirrored an argument rejected in Raytheon Co. v. United States, Civ. No. 05-448, 2009
WL 1373959, at * 1 (Fed.Cl. May 13, 2009). The Court sees nothing in Zoltek’s renewed
argument that would cause it to reconsider its previous ruling.

        Zoltek’s argument could perhaps be characterized as an attempt to cast doubt upon Dr.
Sullivan’s testimony. To this end, the Court notes that it found Dr. Sullivan’s testimony
credible. To the extent that this is Zoltek’s intended purpose with its argument, it is rejected.

       Zoltek next challenges Dr. Sullivan’s testimony because his mathematical model,
whereby he demonstrated that the ‘162 Patent could be reproduced by a combination of well-
known mathematical equations and the prior art, has never been used by any manufacturer. It is
unclear for precisely what purpose Zoltek raises this issue, but to the extent that Zoltek raises it
to counter the Government’s prima facie case of obviousness, Zoltek has cited no cases to
explain the relevance. To the extent that Zoltek intends this argument to apply to its secondary
considerations position, the Court addresses those considerations below.

       The remainder of Zoltek’s challenges to Dr. Sullivan’s can be logically linked to the
substantive arguments before the Court, so they will be addressed where most appropriate.

                               2. The Graham Factors

        The Government’s argument for obviousness is clear and concise. Zoltek’s opposing
argument, on the other hand, can best be characterized as scattershot. Rather than chasing each
rabbit down its hole, the Court organizes its discussion in as direct a manner as possible.

        The Government argues that Dr. Sullivan’s testimony establishes the obviousness of the
‘162 Patent. At trial, Dr. Sullivan testified that the steps embodied in claims 1-22 and 33-38 can
be divided into three categories: (1) steps for processing the carbon fibers themselves by
oxidizing and stabilizing them then performing carbonization and heat treatment; (2) steps for
producing carbon fiber paper or carbon sheet products; and (3) controlling surface resistivity of
the sheet product by means of controlling the heat treatment temperature. Tr. 163-64. Dr.
Sullivan then testified as to how the various prior art references map onto these categories.

        Dr. Sullivan testified that both Shindo and Fischbach and Komaki were relevant to
Category 1. Tr. 101-02. He testified that these references demonstrate the relationship between
the “starting material and heat treatment temperature and the resulting carbon fiber properties.”

                                                 13
Tr. 102. The Government also observes that the ‘162 Patent itself acknowledges that the change
in resistivity of single fibers based upon heat treatment was known at the time of filing. See ‘162
Patent at 5:38-49; Jt. Stip. ¶ 6. On the basis of these facts, Dr. Sullivan opined that Category 1
was “clearly within the state of the art.” Tr. 166. Because all of the sources relied upon by Dr.
Sullivan predate 1983, they qualify as prior art for purposes of obviousness. This conclusion is
bolstered by Mr. Rumy’s testimony at trial, wherein he admitted that he believed similar methods
of making carbon fibers were well known prior to the filing date of the patent. Tr. 342.

         Category 2, the processes for making sheet products such as paper, was also known in the
art. Not only does the ‘162 Patent itself cite a textbook on making paper, see ‘162 Patent 6:28-
35, but Dr. Sullivan testified that Topchjiev, Kitago and Layden all describe production of
carbon paper sheet products. Tr. 167. Based on these references, Dr. Sullivan opined that
Category 2 was the state of the art prior to 1984. Tr. 166-67. Once again, Mr. Rumy also
testified that processes for making carbon fiber paper products were known prior to the filing of
the patent application. Tr. 342-43.

        Category 3, the correlation between carbonization temperature and surface resistivity of
the final sheet product, is really the meat of the ‘162 Patent’s claim of novelty. Dr. Sullivan
explained that the prior art references relevant to this category are Layden, Topchjiev and the
Rule of Mixtures references. At trial, he explained that, prior to 1984:

               There was a desire to control electrical conductivity, to control volume
           resistivity, and to control surface resistivity. They’re all related quantities.
           Simple expressions allow you to know how the conductivity is related to
           the volume resistivity and how the volume resistivity is related to the
           surface resistivity. Very simple algebraic equations.

Tr. 105-06. He then demonstrated the application of these equations. See D85. He also
demonstrated the application of the Rule of Mixtures. Tr. 114-15 (producing D86).

        Combining the calculations for resistivity/conductivity and the Rules of Mixtures, Dr.
Sullivan explained that, in order to calculate surface resistivity for a sheet product, in light of the
prior art, a person of ordinary skill in the art would need only to know the fiber’s volume
resistivity, the fiber’s volume fraction within the composite, the fiber orientations, and the final
thickness of the product. Tr. 145-46. He applied this calculation in a spreadsheet, see D80, and
plotted the results. The degree of similarity between his calculated values and the data reflected
in Fig. 4 of the ‘162 Patent is striking. Compare D80.1 with ‘162 Patent Fig. 4.

         Zoltek argues that Dr. Sullivan’s calculations are materially deficient because he used
incorrect values for various parts of his calculations. First, Zoltek notes that the ‘162 Patent
states that the density of the carbonized and stabilized fibers (i.e., the density after stabilization
and oxidation but prior to heat treatment) is about 1.36 g/cm3, while Dr. Sullivan’s calculations
used a density of 1.81 g/cm3. Compare ‘162 Patent 4:51-52 (stating that the starting material has
“a density of about 1.36 grams per cubic centimeter.”), with D80.2 (using 1.81 g/cm3 as the
density). However, Dr. Sullivan explained that the density of the fiber would increase with heat
treatment temperature, and the Court notes that the graph produced by Dr. Sullivan is actually

                                                  14
more accurate at higher temperatures, which supports his thesis that density increases with heat
treatment temperature. Because Dr. Sullivan’s calculation method is a fact for purposes of this
litigation, the Court recalculated the surface resistivity using the 1.36 g/cm3 value at 775 degrees
Centigrade, which is the lowest temperature in Dr. Sullivan’s chart, and it actually results in a
closer approximation to the measured sheet resistivity than the 1.81 g/cm3 value.5 Thus, it seems
to the Court that the correct density value, which changes at different temperatures, did not
substantially alter Dr. Sullivan’s calculations.

        The other value Zoltek challenges is Dr. Sullivan’s use of .3 as the fiber volume fraction
in his calculations. This challenge made for an interesting series of events at trial. It was first
raised on Zoltek’s cross-examination of Dr. Sullivan, during which Dr. Sullivan testified that he
selected the .3 (30%) value based on his experience that fiber volume fractions typically range
from 20% to 35%. Tr. 260-61. Zoltek’s counsel then asked Dr. Sullivan if he would be
surprised to learn that the volume fraction is actually closer to .03 (3%). Tr. at 263 (“Would you
be surprised to learn that the estimated fiber volume fraction in the Zoltek sheet product
described in the Zoltek patent is 0.03?”). On direct examination, Mr. Rumy then testified that
Zoltek used a fiber volume fraction of 2.5-3%. The Government, on cross, then asked Mr. Rumy
about Joint Exhibit 37, a Stackpole document from 1984. The document showed fiber volume
fractions on the order of 15-30%. See J37.9. Mr. Rumy testified that the document did not refer
to the process described in the ‘162 Patent. Tr. 366-67. The Court finds this testimony not
credible because the document contains a flowchart that is virtually identical to Figure 1 of the
‘162 Patent. Compare J37.3, with ‘162 Patent at Fig. 1. In light of J37 and Zoltek’s failure to
offer any credible evidence to the contrary, the Court finds that Dr. Sullivan’s .3 value was
reasonable in light of his experience and the Stackpole document. Even though Dr. Sullivan did
not testify that he relied upon J37 in using the .3 value, the document corroborates his selection
of .3 based on his experience and lends further credence to his testimony.

        In sum, the Government, by way of Dr. Sullivan’s testimony and the trial record, has
established that all the elements of claims 1-22 and 33-38 were present in the prior art. With this
point established, the Court turns to the question of whether the Government has established that
there was a reason to combine the references.

                              3. The Government Has Established a Motivation to Combine
                                 the Prior Art References

        In looking to the reason to combine, KSR rejected a rigid approach to the obviousness
inquiry. See KSR, 550 U.S. 415-22. Instead, the Supreme Court “required an analysis that reads
the prior art in context, taking account of ‘demands known to the design community,’ ‘the

5
  According to D80.2, Dr. Sullivan calculated a surface resistivity of 3390 ohm/sq and the
measured resistivity was 2290 ohm/sq. Applying the 1.36 g/cm3 value, the Court obtained a
calculated surface resistivity of 3087.85 ohm/sq. It should be noted that the calculation at 775
degrees Centigrade is the least accurate calculation on Dr. Sullivan’s chart. Thus, it would seem
that if Dr. Sullivan was provided with the actual fiber densities—which values Zoltek did not
provide him throughout the extensive history of this litigation—his calculations would likely
prove even more accurate than they already are.
                                                15
background knowledge possessed by a person having ordinary skill in the art,’ and ‘the
inferences and creative steps that a person of ordinary skill in the art would employ.” Randall
Mfg. v. Rea, 733 F.3d 1355, 1362 (Fed. Cir. 2013) (quoting KSR, 550 U.S. at 418). Such an
inquiry “not only permits, but requires, consideration of common knowledge and common
sense.” DyStar Textilfarben GmbH & Co. Deutschland KG v. C.H. Patrick Co., 464 F.3d 1356,
1367 (Fed. Cir. 2006) (emphasis in original).

        There are really two issues raised in Zoltek’s brief with respect to the motivation element.
First, Zoltek argues that Dr. Sullivan has simply not explained why someone would combine the
prior art references in the manner he explained. Second, Zoltek highlights Dr. Sullivan’s
inability to point to a single entity which applied his mathematic calculations in commercial
practice. The Government argues that Dr. Sullivan’s testimony speaks for itself; he clearly
explained why he thought a person of ordinary skill would seek to combine the references.

        The first argument simply ignores Dr. Sullivan’s clear testimony at trial. Contrary to
Zoltek’s assertion, Dr. Sullivan stated his opinion that, based on the teachings of Layden and
Topchjiev, there was a desire to control electrical conductivity, volume resistivity, and surface
resistivity in carbon fiber sheet products. See Tr. 105-06. This reliance upon the prior art itself
is in accord with the Federal Circuit’s flexible post-KSR approach to obviousness: “One form of
evidence to provide such a foundation [to support a party’s claim of obviousness], perhaps the
most reliable because not litigation-generated, is documentary evidence consisting of prior art in
the area.” Randall, 733 F.3d at 1362-63. Similar to the common-sense approach applied in
Randall, Dr. Sullivan explained that the prior art demonstrated that heat treatment temperature
had an effect on both volume resistivity of carbon fibers and on carbon sheet resistivity.

         Recalling Dr. Sullivan’s explanation of the prior art,6 the evidence strongly supports the
notion that the method claimed in the ‘162 Patent is nothing more than an extension of the
phenomenon observed in the prior art. Whereas the prior art recognized that there was a
relationship between heat treatment temperature and resistivity, each reference only presented a
couple of data points. After seeing this relationship in several references, a person of ordinary
skill and with a modicum of common sense and creativity would certainly have seen reason to
test the relationship across a broader range of temperatures. See Perfect Web Techs., Inc. v.
InfoUSA, Inc., 587 F.3d 1324, 1329 (Fed. Cir. 2009) (explaining that “the sources of information
for a properly flexible obviousness inquiry include… ‘any need or problem known in the field of
endeavor at the time of invention and addressed by the patent’”) (citing KSR, 550 U.S. at 418-
21).

         Dr. Sullivan also explained the motivation behind the application of the Rule of Mixtures
in this case. He explained that his mathematical model would have been desirable to anyone
producing sheet products to minimize the costs of expensive trial and error. Tr. 157-61. This
cost-saving benefit is exactly the type of design incentive or market force the Supreme Court
highlighted in KSR. See KSR, 550 U.S. at 401 (“When a work is available in one field, design

6
  Dr. Sullivan explained that Shindo and Fischbach and Komaki demonstrated the temperature-
resistivity relationship of carbon fibers, while Kitago, Layden and Topchjiev demonstrated the
same relationship in carbon fiber sheet products. See supra.
                                                16
incentives and other market forces can prompt variations of it, either in the same field or
another.”).

        The only question remaining is whether the ‘162 Patent comprises predictable art. See
KSR, 550 U.S. at 421 (emphasizing predictability as a concern in the obviousness inquiry).
“[T]o the extent an art is unpredictable, as the chemical arts often are, KSR’s focus on …
identified, predictable solutions may present a difficult hurdle because potential solutions are less
likely to be genuinely predictable.”). Procter & Gamble Co. v. Teva Pharmaceuticals USA, Inc.,
566 F.3d 989, 996 (Fed. Cir. 2009) (internal quotations and citations omitted). Zoltek argues that
the ‘162 Patent is not predictable because it is in the field of organic chemistry, but it offers no
other explanation or evidence of unpredictability. Meanwhile, Dr. Sullivan’s calculations
produced such an accurate representation of Zoltek’s experimental data that the Court can only
conclude that, at least with respect to the technology described in the ‘162 Patent, the art was
plainly predictable.

        Zoltek also attempts to argue against the reasons for combining by noting that Dr.
Sullivan was unable to cite any company that applied his mathematical method. This argument
is unpersuasive for two reasons. First, Zoltek has not cited any case that necessitates commercial
application for obviousness-type invalidity. Second, a reason for the lack of commercial
application may be derived from Mr. Rumy’s own testimony: Zoltek never made any large-scale
sales of the products made by way of the ‘162 Patent and Zoltek stopped marketing its partially-
carbonized fibers shortly after the company acquired Stackpole. Tr. at 376-77 (Mr. Rumy
testifying that, “right around the time I acquired the company, we were still interested in that
business [producing controlled resistivity carbon fiber products], and we did some [marketing]
until we realized we were not going to get any of it.”). Simply put, it appears likely that nobody
performed the kind of mathematical calculations described by Dr. Sullivan because the product
was not particularly effective or desirable.

                      iii. Secondary Considerations

        Any assessment of obviousness also requires review of existing secondary considerations
of non-obviousness. See Zoltek Corp. v. United States, 86 Fed.Cl. 738, 746 (2009) (“It is well-
settled that, if present, a Court must consider evidence of secondary indicia of non-
obviousness.”). The question is generally whether the evidence of the secondary considerations
is strong enough to overcome a showing of obviousness. See, e.g., Asyst Techs., Inc. v. Emtrak,
Inc., 544 F.3d 1310, 1316 (Fed. Cir. 2008) (“evidence of secondary considerations does not
always overcome a strong prima facie showing of obviousness”).

        Evidence of secondary considerations may support a finding of non-obviousness or raise
doubt as to the obviousness of the patented claims. The strength of the evidence depends upon
the nexus between the claimed invention and the secondary consideration. Ormco Corp. v. Align
Tech., Inc., 463 F.3d 1343, 1352 (Fed. Cir. 2010). The patentee must provide, for example,
“probative evidence that the claimed and novel features met a long-felt but unresolved need” or
evidence that shows that the praise of the patented invention or failure of others is a result of the
claimed invention. Id. at 1313. Because this evidence of secondary considerations is intended to

                                                 17
rebut the Government’s prima facie showing of obviousness, Zoltek bears the burden of
producing this evidence.

         In Zoltek’s pre-trial brief, it raised two sources of evidence for the Court’s secondary
considerations analysis: a letter written by George Rodgers, a materials engineer at Northrop
Grumman Corporation (“Northrop”) (J3.191) (hereinafter, “Rodgers Letter”), and a 1982 article
by Quick and Mate. The trial record includes two articles by Quick and Mate (J40 and J118),
both published in 1982, so it is unclear to which publication Zoltek is referring in its pre-trial
brief. The point is irrelevant, however, because Zoltek did not mention either article in its post-
trial brief. Accordingly, the Court assumes Zoltek has abandoned this argument. This leaves the
Rodgers Letter as Zoltek’s only evidence of secondary considerations.

       The Rodgers Letter is part of the prosecution history of the original ‘395 Patent. It is
dated August 6, 1987, and addressed from Mr. Rodgers to Jerry Fleming, then a Stackpole
employee. J3.191. The letter, in its entirety, reads:

               In December 1983, the Materials & Processes Department of Northrop
           Advanced Systems Division ordered four rolls of carbon fiber paper from
           Stackpole Fibers Co. The product was unique in that the carbon fibers
           were not fully carbonized, increasing the volume resistivity of the fiber
           which in turn increases the surface resistivity of the paper. Northrop
           purchased four different levels of resistivity ranging from 24 to 3000
           ohms/square. At the time the order was placed, Northrop Materials &
           Processes had never seen a material of this type before and was not aware
           of any other company that could supply material in this form with varying
           electrical properties.

J3.191. Zoltek argues that this letter and Mr. Rodgers’ deposition testimony support the validity
of the ‘162 Patent, while the Government argues, in short, that the letter is irrelevant.

         Zoltek does not clearly state what secondary consideration the Rodgers Letter is intended
to address, but the Court divines that it is intended to represent industry praise. In its pre-trial
brief, for example, Zoltek asserts that the Rodgers Letter “corroborat[es] the unexpected and
extraordinary properties of the product produced by the Zoltek patent.” Zoltek Pre-trial Br. at 7.
Zoltek also attempts to characterize the letter as an admission by the Government because
Northrop was a Government contractor. Id.

        Neither of these arguments holds water. First, although this Court recognized at
summary judgment that the Rodgers Letter is “reasonably attributable to the ability to vary the
electrical surface resistivity of the products [Northrop] purchase[d],” it left the ultimate
resolution of the issue to trial. Zoltek Corp. v. United States, 95 Fed.Cl. at 705. The only
additional evidence before the Court in addition to this letter is Mr. Rodgers’ testimony and the
stipulations of the parties. While the Rodgers Letter can be said to “praise” the products
produced by way of the ‘162 Patent, nothing in the evidence suggests that this was a particularly
groundbreaking innovation. Indeed, after the first order used for testing the carbon fiber paper,
Northrop never made any additional purchases. See J64.30-35. This testimony was supported

                                                 18
by Mr. Rumy himself, who testified that Zoltek exited the business shortly after acquiring
Stackpole. Tr. 376.

        Zoltek’s assertion that the Rodgers Letter is an admission by the Government borders on
ludicrous. In its pre-trial brief, Zoltek argued that, as an employee of a Government contractor,
Mr. Rodgers’ statements constitute binding admissions by the Government. Zoltek Pre-trial Br.
at 7-8. Zoltek relies primarily on Federal Rule of Evidence (“FRE”) 801(d)(2)(C), arguing
essentially that this is a statement against interest, and on Pacific Gas & Elec. Co. v. United
States, 73 Fed.Cl. 333, 440 (2006), rev’d in part on other grounds, 536 F.3d 1282 (Fed. Cir.
2008).

        FRE 801(d)(2) provides that a statement is not hearsay if it is offered against the
opposing party and “was made by a person whom the party [here, the Government] authorized to
make a statement on the subject.” FRE 801(d)(2)(C). Applying the rule derived in Pacific Gas,
such a statement would be admissible here under FRE 801(d)(2)(C) if the statements are (1)
beneficial to, and offered at trial by, Zoltek, and (2) such statements were “authorized” by the
Government. See Pacific Gas, 73 Fed.Cl. at 440. Unfortunately, while Mr. Rodgers’ statement
may be beneficial to Zoltek, Zoltek has failed to establish that the statements were “authorized”
by the Government. At best, it appears that Mr. Rodgers worked for Northrop’s Advanced
Systems Division, whose “flagship was the design and validation and production of the B-2,”
J66.34, one of the aircraft at issue in this litigation. However, Zoltek has not pointed the Court to
any evidence in the voluminous record before it that explicitly shows that the four rolls of paper
ordered in December 1983 were used for the B-2, or any other Government project.7

                      iv. The ‘162 Patent is Invalid Under 35 U.S.C. § 103

       In sum, Zoltek has failed to establish any serious evidence of secondary considerations
under the Graham framework. The meager evidence presented, when weighed against the
Government’s strong prima facie showing of obviousness, does not render the ‘162 Patent non-
obvious. For the reasons explained above, the Court concludes that, based on the evidence
presented at trial, claims 1-22 and 33-38 of the ‘162 Patent are invalid as obvious under 35
U.S.C. § 103.

7
  The Court recognizes that this deficiency may be due to Zoltek’s inability to obtain the
evidence after the Government invoked the state secrets privilege. Unfortunately, the relevant
law requires the Court to proceed as if this evidence did not exist. See Zoltek Corp. v. United
States, 86 Fed.Cl. 738, 747 (2009) (observing that “the effect of a successful invocation of the
state secrets privilege ‘is simply that the evidence is unavailable, as though a witness had died,’
and that, with this in mind, ‘the case will proceed accordingly.’”) (quoting Ellsberg v. Mitchell,
709 F.2d 51, 64 (D.C. Cir. 1983)). That fact does not excuse Zoltek from the burden of
producing actual evidence of secondary considerations.
                                                 19
       V.      Claims 1-22 and 33-38 of the ‘162 Patent Are Invalid Under 35 U.S.C. § 112

        The Government argues that all of the independent claims-at-issue (claims 1, 11, 15 and
33) are invalid under 35 U.S.C. § 112, ¶ 1 .8 Before turning to the merits, however, the Court
will address a procedural issue raised by Zoltek prior to trial.

               a. Zoltek’s Motion in Limine to Exclude the Government’s § 112, ¶ 1
                  Defense

        Prior to trial, by way of a motion in limine, Zoltek moved this Court to exclude the
Government’s §112, ¶ 1 affirmative defense. Generally put, Zoltek’s justification was that the
Government failed to update its responses to Zoltek’s interrogatories regarding the legal and
factual basis for its §112 defense “as required by Rules 26(b) and (e) and Rule 33” of the RCFC.
See Docket No. 497 at 1. After reviewing the authority cited by Zoltek, the Court denied
Zoltek’s motion “without prejudice to Zoltek raising the issue again after trial.” Docket No. 511
at 1.

         Rather than raising the issue anew post-trial, Zoltek opted to substantively join the
Government’s § 112 theory. See Zoltek Post-Trial Brief at 34-38. Based on Zoltek’s failure to
raise its procedural argument, the Court concludes that Zoltek has abandoned the position. As
such, the Court will turn to the merits of the Government’s argument.

               b. The Government’s Invalidity Contentions Under § 112, ¶ 1

         The ‘162 patent is a reissue of the ‘395 patent. In general, the issue before the Court is
whether the claims and specification in the reissue patent go beyond the written description of
the invention in the original patent application.

         Specifically, the parties’ dispute resolves itself into two separate questions. The first
question is whether the specification, as originally filed, contains support for the amended claim
language calling for “previously oxidized and stabilized” starting material, as opposed to
affirmatively requiring a step of oxidizing and stabilizing. The Government argues that this
amendment is not supported by the as-filed specification. Zoltek counters that the scope of the
claims is unchanged, essentially driving at the point that the amendment is a superficial change
made to accommodate changes in the market that allow for purchase of pre-made starting
material.

        The second question is whether the amendment impermissibly removed the requirement
that oxidation occurs on the “order of 220 Degrees Centigrade to effect molecular aromatic
rearrangement.” See J2.133-J2.136 (specification amendments); J2.175-J2.181 (accepted claim

8
  The America Invents Act amended § 112 in generally cosmetic ways, but those amendments
are not applicable to this case. See Pub.L. No. 112-29, sec. 4(c), 125 Stat. 284, 297 (explaining
that these amendments will not take effect until September 16, 2012, and only apply to patent
applications filed on or after September 16, 2012). Thus, the prior version of § 112 applies in
this case.
                                                 20
amendments). The Government argues that the removal of this requirement violates Federal
Circuit precedent, such that the claims must be found invalid. Zoltek’s brief does not directly
address this point.

        In order to better understand the Government’s written description argument, a brief
review of the history of the ‘162 Patent is worthwhile. Three trial exhibits are relevant to the
Government’s § 112 challenge: J1, the ‘162 Patent; J2, the prosecution history for the ‘162
Patent; and J3, the prosecution history for the ‘395 Patent.

        The application that matured into the ‘395 Patent was filed on October 12, 1984, and it
issued on March 1, 1988. Less than two years later, on February 20, 1990, Zoltek filed an
application seeking reissue of the ‘395 Patent: (1) “for the reason that the specification and
claims thereof are defective and insufficient … through inadvertence and oversight,” (2) to
“more clearly describe and claim the invention in conformance with the requirements of 35
U.S.C. § 112,” (3) to establish “the patentably distinguishing features of the Boyd invention over
the cited prior art,” and (4) to add “a set of new claims … rephrased … to more precisely point
out what is believed to be patentably novel.” J2.31-33. During these reissue proceedings, Zoltek
amended some of the claim language, as demonstrated in claim 1:

                    A method of manufacturing a plurality of different value controlled
           resistivity carbon fiber sheet products employing a carbonizable starting
           material; said method comprising [oxidizing and stabilizing the
           carbonizable fiber starting material at an elevated temperature of the
           order of 220 degrees Centigrade to effect aromatic rearrangement of
           the fibers,] selectively partially carbonizing [the] previously oxidized and
           stabilized fiber starting material for a predetermined period in an oxygen
           free atmosphere within a furnace at [a] selected temperature values within
           a temperature range from 370 degrees Centigrade to about 1300 degree
           Centigrade by soaking the stabilized fiber starting material at the selected
           temperature for the predetermined period of time to provide a [desired]
           preselected known volume electrical resistivity to the partially carbonized
           fibers corresponding to that volume electrical resistivity value required to
           provide the preselected desired surface resistance value for the finished
           sheet products, and thereafter processing the partially carbonized fibers
           into [desired electrical resistivity] homogeneous carbon fiber sheet
           products [having the form of non-woven paper or woven or knitted fabric
           sheet products] having the preselected desired surface electrical
           [resistivities] resistances.

‘162 Patent at 8:42-66 (bold added, italics in original).9

        The specification was also amended during reissue. Of particular relevance to the issues
raised by the Government is the following amended statement, in context:

9
  Recall that brackets indicate removal of language from the original claims, and italics indicate
language added during reissue proceedings.
                                                 21
                  After heating and drawing the carbonizable material is oxidized at
           an elevated temperature of the order of 220 degrees Centigrade to effect
           aromatic molecular rearrangement of the starting material. In the event the
           precursor starting material previously has been stabilized and oxidized by
           a supplier of such material, then this step may be eliminated.

‘162 Patent 2:32-38. The italicized language was added during reissue proceedings.

      With this background in mind, the Court turns to the issues raised by the
Government at trial. 35 U.S.C. § 112, ¶ 1 states:

               The specification shall contain a written description of the invention,
           and of the manner and process of making and using it, in such full, clear,
           concise, and exact terms as to enable any person skilled in the art to which
           it pertains, or with which it is most nearly connected, to make and use the
           same, and shall set forth the best mode contemplated by the inventor of
           carrying out his invention.

This single paragraph is a patent defendant’s Swiss Army Knife: it places several distinct
burdens upon a patent applicant, each of which must necessarily be met to obtain a valid patent.
Fortunately, the Government only raises one of these burdens: written description.

        The determination of whether a patent complies with the written description requirement
is a question of fact. Ariad Pharmaceuticals, Inc. v. Eli Lilly and Co., 598 F.3d 1336, 1351 (Fed.
Cir. 2010) (en banc). “[T]he test for sufficiency is whether the disclosure of the application
relied upon reasonably conveys to those skilled in the art that the inventor had possession of the
claimed subject matter as of the filing date.” Id. “The purpose of the written description
requirement is to ensure that the scope of the right to exclude, as set forth in the claims, does not
overreach the scope of the inventor’s contribution to the field of art as described in the patent
specification.” Id. at 1353-54.

        The first question is whether the specification, as originally filed, contains support for the
amendment calling for “previously oxidized and stabilized” starting material, as opposed to
requiring a step of oxidizing and stabilizing.

       In general, Zoltek’s position in its post-trial brief is that the Government’s § 112 ¶ 1
argument has already been rejected by the Court in its decision on the Government’s earlier
Motion for Partial Summary Judgment based on § 112 ¶ 2. See Zoltek Corp. v. United States,
Civ. No. 96-166, Docket No. 90 (Fed. Cl. Sept. 23, 1999); see also Zoltek Post-Trial Br. at 35,
37-38. Zoltek’s position, however, immediately raises the question of how a decision based on
one part of a statute automatically disposes of an argument based on another part of a statute. In
other words, it is more logical to assume that decisions based on different parts of a statute are
independent of one another rather than that one decision compels the same result in another.
Thus, Zoltek needs to persuade the Court how its ¶ 2 decision determines its ¶ 1 decision.

                                                 22
        Zoltek’s argument on this point is imprecise. It notes that the issue in the ¶ 2 decision
was indefiniteness due to a lack of a proper antecedent basis, which characterization is correct.
Zoltek then quotes extensively from the Court’s ¶ 2 opinion, but with no argument on how the
quoted text relates to the Government’s ¶ 1 argument in this phase of the case. Zoltek ends its
discussion of the Court’s ¶ 2 with the following conclusory remark:

               This Court thoroughly dealt with this issue in its September 13, 1999
           Opinion… Asserting the same factually insufficient arguments to support
           a §112 lack of written description defense is simply a waste of this Court’s
           time.

Zoltek Post-Trial Br. at 38.

        The touchstone for determining whether a claim is indefinite was stated in the Court’s ¶ 2
decision: “Whether a claim is invalid under § 112 ¶ 2 requires a determination as to whether
those skilled in the art would understand what is claimed when the claim is read in light of the
specification.” See Zoltek Corp. v. United States, Civ. No. 96-166, Docket No. 90, at 3-4
(quoting Messerschmidt v. United States, 29 Fed.Cl. 1, 41 (1993)). In its decision, the Court was
asked to compare the claims and the specification to see whether there was an antecedent basis
for the claims in the reissue patent that eliminated the step of oxidizing and stabilizing. The
Court found that there was an antecedent basis such that one skilled in the art would be able to
understand the scope of the claims in the reissue patent. Whether the claims and specification
went beyond the written description is another matter. If this were not so, why would § 112 have
a ¶ 1 and a ¶ 2? The most that the Court can discern in Zoltek’s post-trial brief argument on this
issue is that the facts are identical in the Government’s arguments regarding ¶¶ 1 and 2. See
Zoltek Post-Trial Br. at 35, 37-38.

        Considering Zoltek’s vague argument and examining its earlier decision and the different
question presented to it now, the Court does not agree that its earlier opinion is controlling of the
issue now at bar. Again, that decision was reached in the context of 35 U.S.C. § 112, ¶ 2, under
which provision the Government argued that the claims were indefinite for lack of an antecedent
basis because the “oxidizing and stabilizing” step had been deleted. The Court’s decision relied
upon a sentence added during reissue proceedings, namely, the statement that “[i]n the event the
precursor starting material previously has been stabilized and oxidized by a supplier of such
material, then this step [oxidizing and stabilizing the starting material] may be eliminated.” See
Zoltek Corp. v. United States, Civ. No. 96-166, Docket No. 90 at 5 (quoting ‘162 Patent at 2:36-
38).

        The Court reached its conclusion in part on the basis of the amended specification. It is
precisely that amendment that the Government now challenges, and the Court agrees with the
Government’s position. Nothing in the original specification disclosed the possibility that the
starting material could be oxidized and stabilized outside the confines of the described method
(as the amended claims suggest), and as such, the specification amendment is unavailing.

                                                 23
       The fact that oxidation and stabilization was allegedly part of the prior art, which fact the
Court also relied upon in the 1999 Opinion, is irrelevant to the question of whether the written
description requirement is satisfied. As the Federal Circuit recently stated,

                To satisfy the written description requirement, a patent applicant must
           convey with reasonable clarity to those skilled in the art that, as of the
           filing date sought, he or she was in possession of the invention. The
           invention is, for purposes of the “written description” inquiry, whatever is
           now claimed. Such description need not recite the claimed invention in
           haec verba but most do more than merely disclose that which would
           render the claimed invention obvious.

ICU Medical, Inc. v. Alaris Medical Systems, Inc., 558 F.3d 1368, 1377 (Fed. Cir. 2009)
(citations omitted; emphasis in original); see also PowerOasis, Inc. v. T-Mobile USA, Inc., 522
F.3d 1299, 1306-07 (Fed. Cir. 2008) (explaining that § 112, ¶ 1 “requires that the written
description actually or inherently disclose the claim element”). As the Government asserts, the
original specification discloses nothing that suggests a method calling for a previously oxidized
fiber. It repeatedly calls for the party performing the steps of the invention to oxidize and
stabilize the starting material as part of the description of the invention. As such, purchasing the
pre-made starting materials was not disclosed in the original specification and independent
claims 1, 11, 15 and 33 and those claims which depend upon them are invalid for lack of written
description.

        The second question focuses in on the temperature requirement in contrast to the broader
point of the stabilization and oxidation step of the first question. With respect to the question of
whether the temperature requirement has been removed from the claims, the Court also finds that
the claims are invalid. Once again, the disclosure contained in the specification consistently
refers to the necessity of performing the oxidizing and stabilizing step at a temperature of the
order of 220 degrees Centigrade in order to effect aromatic rearrangement of the molecules of
the starting material. See ‘162 Patent at 2:33-35; 3:33-36; 4:46-49. In each instance where the
oxidation and stabilization step is discussed (in both the original specification and the amended
specification), the specification emphasizes the need to perform the step at an elevated
temperature to achieve aromatic rearrangement. This temperature requirement, repeatedly
emphasized in the original specification, is conspicuously absent from all of the reissued claims.

        In effect, then, the amended claims call for oxidation and stabilization at any temperature,
while the original specification makes quite clear that this step must occur at a temperature on the
order of 220 degrees Centigrade. This constitutes new matter, which may not be added during
prosecution of the patent application. See Baldwin Graphic Systems, Inc. v. Siebert, Inc., 512
F.3d 1338, 1344 (Fed. Cir. 2008). The Baldwin case is instructive because it addressed a very
similar modification: in that case, the applicant amended a claim limitation from “heat-sealed
sleeve” to “sealed sleeve.” Id. The Federal Circuit noted that allowing the claim term to be read
as only requiring a “sealed sleeve” would broaden the patent beyond the original disclosure. Id.
As here, the applicant in Baldwin sought to remove a temperature-based requirement from the
claims despite the fact that the originally-filed specification emphasized temperature. Thus, the
Court finds that Baldwin is essentially on all fours with the issue now before the Court.

                                                 24
        In sum, the written description and the claims in the original patent do not support the
elimination of the oxidization and stabilization step and the elimination of oxidizing and
stabilizing according to the temperature requirement.10 Doing so impermissibly broadens the
patented process by reducing the number of steps required for infringement. A potential
infringer need not practice the oxidation and stabilization step at the required temperature in
order to infringe the ‘162 Patent, whereas that step was necessary in the ‘395 Patent. For that
matter, a potential infringer need not practice the oxidation and stabilization step at all to infringe
the ‘162 Patent. It is enough to purchase starting material that was previously oxidized and
stabilized, regardless of how that oxidation and stabilization was achieved.

        For these reasons, the Court concludes that claims 1, 11, 15 and 33 (and all claims which
depend therefrom) are invalid under 35 U.S.C. § 112, ¶ 1. There is no evidence in the trial
record to support a conclusion that the originally filed disclosure of October 12, 1984, contained
support for either (1) a method calling for previously oxidized fiber or (2) a method calling for
oxidation at a temperature other than “at an elevated temperature of the order 220 Degrees
Centigrade to effect molecular aromatic rearrangement of the starting material.”

       VI.     Conclusion

         After extraordinarily long proceedings and after hearing the testimony at trial, the Court
is satisfied by the Government’s arguments that the ‘162 Patent’s claims at issue (claims 1-22
and 33-38) in this litigation are invalid under 35 U.S.C. §§ 103 and 112. Judgment in favor of
the Government is, therefore, appropriate. The Clerk is directed to enter judgment accordingly.

                                                               /s Edward J. Damich
                                                               Edward J. Damich
                                                               Senior Judge

10
   In its previous decision, the Court stated that “it can hardly be said that the oxidizing and
stabilizing step was removed from the Reissue ‘162.” Zoltek Corp. v. United States, Civ. No. 96-
166, Docket No. 90 at 5. In the context of a ¶ 2 argument, this means that the step is referred to
in the claims and the specification and is mentioned in the original patent as well. In the context
of a ¶ 1 argument, although the step is found in the reissue patent, its elimination from the
claimed process goes beyond the written description of the invention in the original ‘395 patent.
                                                  25