Intertrust Technologies Corporation

Patent Trials and Appeals Board

Dec 15, 2021

IPR2020-01123 (P.T.A.B. Dec. 15, 2021)

Trials@uspto.gov Paper 33
571-272-7822 Entered: December 15, 2021

UNITED STATES PATENT AND TRADEMARK OFFICE

BEFORE THE PATENT TRIAL AND APPEAL BOARD

DOLBY LABORATORIES, INC.,
Petitioner,
v.
INTERTRUST TECHNOLOGIES CORPORATION,
Patent Owner.

IPR2020-01123
Patent 6,157,721

Before MICHAEL R. ZECHER, NABEEL U. KHAN, and
CHRISTOPHER L. OGDEN, Administrative Patent Judges.

KHAN, Administrative Patent Judge.
JUDGMENT
Final Written Decision
Determining All Challenged Claims Unpatentable
35 U.S.C. § 318(a)

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I. INTRODUCTION
A. Background and Summary
Dolby Laboratories, Inc. (“Petitioner”) filed a Petition (Paper 2,
“Pet.”) requesting an inter partes review of claims 5, 9, and 29 of U.S.
Patent No. 6,157,721 (Ex. 1001, “the ’721 patent”). Intertrust Technologies
Corporation (“Patent Owner”) filed a Preliminary Response (Paper 7,
“Prelim. Resp.”). With its Preliminary Response, Patent Owner filed a
statutory disclaimer, disclaiming claim 5 of the ’721 patent. See Ex. 2019.
Petitioner and Patent Owner filed additional briefing with our authorization.
See Papers 8, 9. On January 6, 2021, upon consideration of the Petition,
Preliminary Response, the additional briefing, and the statutory disclaimer of
claim 5, we instituted review to determine the patentability of claims 9 and
29 (“the challenged claims”) but did not institute review of claim 5. Paper
10 (“Dec. Inst.”).
After institution, Patent Owner filed a Patent Owner Response (Paper
18, “PO Resp.”), Petitioner filed a Reply (Paper 22, “Pet. Reply”), and
Patent Owner filed a Sur-Reply (Paper 24, “PO Sur-reply”). An oral hearing
was held on October 5, 2021, and the hearing transcript is included in the
record. Paper 32 (“Tr.”).
We have jurisdiction under 35 U.S.C. § 6. This Final Written
Decision, issued pursuant to 35 U.S.C. § 318(a) and 37 C.F.R. § 42.73
(2019), addresses issues and evidence raised during the inter partes review.
For the reasons that follow, Petitioner demonstrates by a preponderance of
the evidence that claims 9 and 29 of the ʼ721 patent are unpatentable.
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B. Related Matters
The parties identify four related district court cases involving the ’721
patent: (1) Dolby Laboratories, Inc. v. Intertrust Corporation, No. 3:19-cv-
03371 (N.D. Cal.); (2) Intertrust Technologies Corporation v. AMC
Entertainment Holdings, Inc., No. 2:19-cv-00265 (E.D. Tex.); (3) Intertrust
Technologies Corporation v. Cinemark Holdings, Inc., No. 2:19-cv-00266
(E.D. Tex.); and (4) Intertrust Technologies Corporation v. Regal
Entertainment Group, No. 2:19-cv-00267 (E.D. Tex.). See Pet. 7; Paper 5,
1.
C. The ’721 Patent
The ’721 patent is titled “Systems and Methods Using Cryptography
to Protect Secure Computing Environments,” and the application giving rise
to the ’721 patent was filed on August 12, 1996, and issued on December 5,
2000. Ex. 1001, codes (21), (22), (54). The application giving rise to the
’721 patent is the only patent application referenced for the benefit of a prior
filing date under 35 U.S.C. § 120 and the ’721 patent has no term
extensions. Accordingly, the term of the ’721 patent has expired. See 35
U.S.C. § 154(a)(2) (2018).
The ’721 patent is directed to systems and methods for protecting
secure processing environments or other secure execution spaces from
unauthorized and potentially harmful “load modules,” other “executables,”
or associated data. Ex. 1001, 1:19–28, 4:51–56. To accomplish this, one or
one or more trusted verifying authorities may validate load modules or other
executables by analyzing or testing them, and a verifying authority may
digitally “sign” and “certify” those load modules or other executables it has
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verified (for example, using a public key based digital signature or
certificate based thereon). See id. at 4:61–67.
Figure 14 of the ’721 patent is reproduced below.

Figure 14 depicts an example of a process according to one embodiment of
the ’721 patent. Ex. 1001, 8:7–10, 20:26–28. As shown in Figure 14, a load
module provider may manufacture a load module and its specifications (step
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502) and submit it to a verifying authority for verification (step 504). Id. at
20:28–32. The verifying authority may analyze, test or otherwise validate
the load module and determine whether it satisfies the specifications (step
506). Id. at 20:32–36. If it determines that the load module satisfies its
specifications, the verifying authority may determine whether it is
authorized to generate one or more new specifications (step 508). Id. at
20:37–40. If it is authorized and this function has been requested (step 509),
the verifying authority may generate the new specifications and associate
them with the load module (step 514). Id. at 20:40–43.
If the load module fails the test, the verifying authority may still
create new specifications that conform to the load module performance
(step 514) if it is authorized to do so, and it would be desirable (step 510).
Ex. 1001, 20:44–49, 20:52–56. Otherwise, the verifying authority may
decide not to create the new specifications, the load module may be rejected
and returned to the provider, and the process ends (step 512). Id. at 20:49–
52. For those load modules in which new specifications have been
generated or created, the verifying authority may digitally sign the load
module to indicate approval by applying or selecting appropriate digital
signatures (step 516). Id. at 20:58–20:63. The verifying authority may then
determine the distribution of the load module (step 518) and distribute the
appropriate information to a value chain (step 520). Id. at 20:63–21:7.
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Figure 3 of the ’721 patent is reproduced below.

Figure 3 of the ’721 patent depicts how a protected processing environment
108 may distinguish load modules 54a that have been approved by the
verifying authority from load modules 54 that have not been approved. Ex.
1001, 7:41–44, 9:52–55. The protected processing environment may
distinguish between authorized and unauthorized load modules by
examining the load module to see whether it bears the seal (e.g., seal 106) of
the verifying authority, which may comprise one or more “digital
signatures.” Id. at 9:53–54, 9:58–61. Protected processing environment 108
may execute load module 54a with its processor 110 only if the load module
bears the verifying authority’s signature 106. Id. at 9:61–64. Protected
processing environment 108 may discard and not use any load module 54
that does not bear this signature 106. Id. at 9:64–66. In this way, protected
processing environment 108 may securely protect itself against unauthorized
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load modules 54 such as defective load module 54d made by a disreputable
load module provider. Id. at 9:66–10:3.
Figure 6 of the ’721 patent is reproduced below.

Figure 6 of the ’721 patent depicts how protected processing environment
108 may “authenticate” a digital signature created by the verifying authority.
Ex. 1001, 7:49–52, 13:60–62. As shown in Figure 6, second key 124 and
the one-way hash transformation function 115 are securely provided to
protected processing environment 108. Id. at 13:62–64. Public key
cryptography allows second key 124 to be made public without
compromising first key 122. Id. at 13:66–14:1. However, in the example
shown in Figure 6, protected processing environment 108 preferably keeps
public second key 124 secret. Id. at 14:1–5. This enhances security by
greatly complicating an attacker’s job of generating bogus digital signatures
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106 and by foreclosing “the significant threat that the owner of protected
processing environment 108 himself may attack the environment.” Id. at
14:1–9, 14:23–26; see also id. at 14:9–22, 14:26–38 (discussing how the
owner could replace public key 124 with his own substitute public key and
force protected processing environment 108 to execute load modules of his
own design).
Load module 54 and its associated digital signature 106 are then
delivered to protected processing environment 108, which applies one way
hash transformation function 115 on load module 54 and generates message
digest 116′. Ex. 1001, 14:39–48. Protected processing environment 108
then decrypts digital signature 106 using second key 124. Id. at 14:49–50.
This process includes opening strongbox 118 to retrieve message digest 116,
which verifying authority 100 placed in strongbox 118 when creating digital
signature 106. Id. at 13:30–35, 14:50–52. Protected processing
environment 108 then compares message digest 116 with message digest
116′—which should be identical. Id. at 14:52–57. If they do not match,
then either digital signature 106 is not authentic or load module 54 has been
changed, so protected processing environment 108 rejects load module 54.
Id. at 14:57–60.
D. Illustrative Claims
Claims 9 and 29 are independent and recite nearly identical
limitations, with claim 9 reciting “load modules” whereas claim 29 recites
“executables.” Compare Ex. 1001, 22:5–15, with id. at 24:10–21.
Claim 9 is reproduced below.
9. A method of distinguishing between trusted and untrusted
load modules comprising:
(a) receiving a load module,
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(b) determining whether the load module has an associated
digital signature,
(c) if the load module has an associated digital signature,
authenticating the digital signature using at least one public key
secured behind a tamper resistant barrier and therefore hidden
from the user; and
(d) conditionally executing the load module based at least
in part on the results of authenticating step (c).
Ex. 1001, 22:5–15.
E. Prior Art and Asserted Grounds
Petitioner asserts that claims 9 and 29 are unpatentable based on the
following grounds:
Claim(s) Challenged 35 U.S.C. § Reference(s)/Basis
9, 29 102(a)1 Arnold2
9, 29 103(a) Arnold
9, 29 103(a) Chang3, Stefik4

In addition, Petitioner relies on the Declaration of Sandeep Chatterjee, Ph.D.
(Ex. 1002) in support of the asserted grounds of unpatentability. See
generally Pet.; Pet. Reply. Patent Owner relies on the Declaration of
Dr. Markus Jakobsson (Ex. 2027) in support of Patent Owner’s Response.
See generally PO Resp.; Sur-reply.

1 The Leahy-Smith America Invents Act (“AIA”), Pub. L. No. 112-29, 125
Stat. 284, 287–88 (2011), amended 35 U.S.C. §§ 102 and 103, effective
March 16, 2013. Because the application from which the ’721 patent issued
claims priority to applications filed before this date, the pre-AIA versions of
§§ 102 and 103 apply.
2 EP 0706275 A2, published April 10, 1996 (Ex. 1004, “Arnold”).
3 US 5,724,425, issued March 3, 1998 (Ex. 1005, “Chang”).
4 US 5,715,403, issued February 3, 1998 (Ex. 1006, “Stefik”).
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II. ANALYSIS
For the reasons discussed below, we determine Petitioner has shown
by a preponderance of the evidence that claims 9 and 29 are anticipated by
Arnold and that claims 9 and 29 would have been obvious over Arnold. We,
however, determine that Petitioner has not shown by a preponderance of the
evidence that claims 9 and 29 would have been obvious over the
combination of Chang and Stefik.
We start first with a summary of the relevant legal standards, then
provide an analysis of the level of skill in the art and claim construction, and
then analyze the parties’ contentions with respect to each of the asserted
grounds.
A. Legal Standards
“In an [inter partes review], the petitioner has the burden from the
onset to show with particularity why the patent it challenges is
unpatentable.” Harmonic Inc. v. Avid Tech., Inc., 815 F.3d 1356, 1363
(Fed. Cir. 2016) (citing 35 U.S.C. § 312(a)(3) (requiring inter partes review
petitions to identify “with particularity . . . the evidence that supports the
grounds for the challenge to each claim”)); see also 37 C.F.R. § 42.104(b)
(requiring a petition for inter partes review to identify how the challenged
claim is to be construed and where each element of the claim is found in the
prior art patents or printed publications relied upon).
“A claim is anticipated only if each and every element as set forth in
the claim is found, either expressly or inherently described, in a single prior
art reference.” Verdegaal Bros. Inc., v. Union Oil Co., 814 F.2d 628, 631
(Fed. Cir. 1987); see also Finisar Corp. v. DirecTV Group, Inc., 523 F.3d
1323, 1334 (Fed. Cir. 2008) (To anticipate a patent claim under 35 U.S.C.
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§ 102, “a single prior art reference must expressly or inherently disclose
each claim limitation.”). Moreover, “[b]ecause the hallmark of anticipation
is prior invention, the prior art reference—in order to anticipate under 35
U.S.C. § 102—must not only disclose all elements of the claim within the
four corners of the document, but must also disclose those elements
‘arranged as in the claim.’” Net MoneyIN, Inc. v. VeriSign, Inc., 545 F.3d
1359, 1369 (Fed. Cir. 2008). This is not an ipsissimis verbis test, however—
identical terminology is not required. See In re Bond, 910 F.2d 831, 832
(Fed. Cir. 1990). Whether a reference anticipates is assessed from the
perspective of an ordinarily skilled artisan. See Dayco Prods., Inc. v. Total
Containment, Inc., 329 F.3d 1358, 1368 (Fed. Cir. 2003) (“[T]he dispositive
question regarding anticipation [i]s whether one skilled in the art would
reasonably understand or infer from the [prior art reference’s] teaching that
every claim element was disclosed in that single reference.”). Additionally,
under the principles of inherency, if the prior art necessarily functions in
accordance with, or includes, the claimed limitations, it anticipates.
MEHL/Biophile Int’l Corp. v. Milgraum, 192 F.3d 1362, 1365 (Fed. Cir.
1999); In re Cruciferous Sprout Litig., 301 F.3d 1343, 1349–50 (Fed. Cir.
2002).
A claim is unpatentable under 35 U.S.C. § 103(a) if “the differences
between the subject matter sought to be patented and the prior art are such
that the subject matter as a whole would have been obvious at the time the
invention was made to a person having ordinary skill in the art to which said
subject matter pertains.” KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 406
(2007). The question of obviousness is resolved on the basis of underlying
factual determinations, including (1) the scope and content of the prior art;
(2) any differences between the claimed subject matter and the prior art;
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(3) the level of skill in the art; and (4) when in evidence, objective evidence
of obviousness or nonobviousness, i.e., secondary considerations. See
Graham v. John Deere Co., 383 U.S. 1, 17–18 (1966).
Additionally, the obviousness inquiry typically requires an analysis of
“whether there was an apparent reason to combine the known elements in
the fashion claimed by the patent at issue.” KSR, 550 U.S. at 418 (citing
In re Kahn, 441 F.3d 977, 988 (Fed. Cir. 2016) (requiring “articulated
reasoning with some rational underpinning to support the legal conclusion of
obviousness”)). Furthermore, Petitioner does not satisfy its burden of
proving obviousness by employing “mere conclusory statements,” but “must
instead articulate specific reasoning, based on evidence of record, to support
the legal conclusion of obviousness.” In re Magnum Oil Tools Int’l, Ltd.,
829 F.3d 1364, 1380 (Fed. Cir. 2016).
B. Level of Ordinary Skill in the Art
Petitioner contends that a person of ordinary skill in the art (a
“POSITA”) at the time the ’721 patent was made would have had a
minimum of a Bachelor of Science degree in computer science, electrical
engineering, or a related field, and approximately one year of professional
experience or equivalent study in distributed computing systems, including
securing those systems. Pet. 17. Petitioner further states that additional
graduate education could substitute for professional experience, or
significant experience in the field could substitute for formal education. Id.
at 17–18 (citing Ex. 1002 ¶¶ 33–34).
Patent Owner sets forth a similar definition, stating that a POSITA at
the time the ’721 patent was filed would have had a Bachelor of Science
degree in electrical engineering and/or computer science, and three years of
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work or research experience in the fields of secure transactions and
encryption, or a Master’s degree in electrical engineering and/or computer
science and two years of work or research experience in related fields. PO
Resp. 19. Patent Owner states that the positions set forth in its Response
would be the same under either party’s proposal. Id.
The parties’ proposals do not differ in any meaningful way to the
issues in dispute. We adopt Petitioner’s articulation of the level of ordinary
skill in the art, except that we delete the qualifier “a minimum” to eliminate
vagueness as to the appropriate level of education. The qualifier expands the
range without an upper bound, i.e., encompassing a Ph.D. degree and
beyond, and thus does not meaningfully indicate the level of ordinary skill in
the art. This definition of a POSITA is supported by the testimony of
Dr. Chatterjee and is commensurate with the level of ordinary skill as
reflected in the prior art and the ’721 patent. We note, however, that our
analysis would be the same under either party’s definition of a POSITA.
C. Claim Construction
In inter partes reviews, we interpret a claim “using the same claim
construction standard that would be used to construe the claim in a civil
action under 35 U.S.C. 282(b).” See 37 C.F.R. § 42.100(b). Under this
standard, we construe the claim “in accordance with the ordinary and
customary meaning of such claim as understood by one of ordinary skill in
the art and the prosecution history pertaining to the patent.” Id. Only claim
terms that are in controversy need to be construed and only to the extent
necessary to resolve the controversy. See Nidec Motor Corp. v. Zhongshan
Broad Ocean Motor Co., 868 F.3d 1013, 1017 (Fed. Cir. 2017).
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1. “load module”
Petitioner argues the term “load module” recited in claim 9 should be
construed as “executable code, such as a computer program or an applet,
plus any associated data required for code execution.” Pet. 19. To support
this proposed construction, Petitioner cites the Specification’s statements
that “[l]oad modules may contain algorithms, data, cryptographic keys,
shared secrets, and/or other information that permits a load module to
interact with other system components,” and “[f]or a load module to operate
and interact as intended, it must execute without unauthorized modification.”
Id. (emphasis omitted) (quoting Ex. 1001, 3:28–35); see also id. at 19–20
(citing Ex. 1001, 4:36, 4:51–56, 5:34–39). Petitioner also points to the
“Field of the Invention” section of the ’721 patent, which provides that
“[t]he present invention relates to . . . techniques for certifying load modules
such as executable computer programs or fragments [(called ‘applets’)]
thereof as being authorized for use by a protected or secure processing
environment.” Id. at 20 (alterations in original) (emphasis omitted) (quoting
Ex. 1001, 1:17–28) (citing Ex. 1001, 2:33–37; Ex. 1002 ¶¶ 67–69).
According to Patent Owner, Petitioner’s proposed construction is
inconsistent with the construction adopted in co-pending litigation of the
related matters, in which the term was construed to mean “executable code
and any associated data.” PO Resp. 22 (citing Ex. 2007, 44). Nevertheless,
Patent Owner contends that the term “load module” does not require
construction and should be given its plain and ordinary meaning. Id. Patent
Owner further asserts that construction of this term is not necessary to
resolve the matters presently in dispute and that its arguments would apply
equally under the construction of the co-pending litigation or under a plain
and ordinary meaning of the term. Id.
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Based on the arguments presented by the parties and the issues raised,
we agree with Patent Owner that no explicit construction of this phrase is
necessary to resolve the disputes between the parties.
2. “associated digital signature”
Patent Owner points out that “the District Court [for the Eastern
District of Texas] adopted a construction of ‘associated digital signature’ as
‘a digital value, verifiable with a public key, that can be used to determine
the source and integrity of the load module/executable.’” PO Resp. 21
(citing Ex. 2001, 1). Nevertheless, Patent Owner contends that the term
“associated digital signature” does not require construction and that its
arguments would apply equally under the District Court’s construction or a
plain and ordinary meaning of the term. Id. at 23. Petitioner does not
provide its own construction of the term “associated digital signature.”
Based on the arguments presented by the parties, we agree with Patent
Owner that no explicit construction of this term is necessary to resolve the
disputes between the parties.
3. Whether limitations (c) and (d) are conditional
Claim 9 recites:
(c) if the load module has an associated digital signature,
authenticating the digital signature using at least one public key
secured behind a tamper resistant barrier and therefore hidden
from the user; and
(d) conditionally executing the load module based at least
in part on the results of authenticating step (c).
Ex. 1001, 22:10–16. Claim 29 recites similar limitations. Id. at 24:16–22.
In its Reply Brief, Petitioner contends that limitations (c) and (d) of
claim 9, and the corresponding limitations of claim 29, are contingent steps
that should not be given patentable weight. Pet. Reply 4–5. Specifically,
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Petitioner argues that steps (c) and (d) “are only performed ‘if the load
module has an associated digital signature.’” Id. According to Petitioner,
the methods of claims 9 and 29 can be achieved by performing only steps (a)
and (b). Id. at 5. Because only the first two steps are required to be
performed, Petitioner argues the Board need not reach the optional method
steps. Id. (citing Ex parte Schulhauser, No. 2013-007847, 2016 WL
6277792 at *4 (PTAB, Apr. 28, 2016) (precedential)).
Patent Owner contends that Petitioner’s argument is a new argument,
never raised in the Petition, and therefore should not be considered. PO Sur-
reply 2–3. Patent Owner further argues that the claimed methods would be
incomplete without limitations (c) and (d) which are necessary to distinguish
between trusted and untrusted load modules and thus those limitations must
be given weight. Id. at 4–5.
We agree with Patent Owner that Petitioner’s argument that
limitations (c) and (d) are conditional is a new argument improperly raised
for the first time in the Reply Brief. Petitioner has the burden to demonstrate
sufficiently in the Petition that the cited prior art renders the challenged
claims unpatentable, including showing that the Petition’s contentions are
supported by evidence. See 35 U.S.C. § 314(a); see also Harmonic Inc., 815
F.3d at 1363 (Fed. Cir. 2016) (“In an IPR, the petitioner has the burden from
the onset to show with particularity why the patent it challenges is
unpatentable.” (emphases added) (citing 35 U.S.C. § 312(a)(3))); Intelligent
Bio-Systems, Inc. v. Illumina Cambridge Ltd., 821 F.3d 1359, 1369 (Fed.
Cir. 2016) (requiring “the initial petition identify ‘with particularity’ the
‘evidence that supports the grounds for the challenge to each claim.’”
(emphases added)). This burden includes setting forth in its Petition “[h]ow
the challenged claim is to be construed.” 37 C.F.R. § 42.104(b)(3).
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The Petition sets forth arguments as to why the cited prior art
references teach limitations (c) and (d) but does not include arguments
indicating that these limitations should not be given patentable weight. See
Pet. 49–55, 56–57, 72–80. In light of the contentions set forth in the
Petition, Patent Owner’s Response focuses on arguing why the cited prior art
references do not teach or disclose these limitations. PO Resp. 21–42. We
do not find anything in Patent Owner’s Response that opens the door to
Petitioner’s new arguments. Thus, we do not find Petitioner’s new position
on claim construction to be permissible reply material and we do not
consider it in making our decision. 37 C.F.R. § 42.23(b) (2021) (“A reply
may only respond to arguments raised in the . . . patent owner response, or
decision on institution.”).
D. Overview of the Cited Prior Art References
1. Overview of Arnold
Arnold, titled “System and method for secure storage and distribution
of data using digital signatures,” generally relates to “an apparatus and
method for secure distribution of software, software updates, and
configuration data.” Ex. 1004, code (54), 5:19–20. Arnold describes the use
of cryptography to protect software or data updates sent to computer
products or peripherals using non-secure distribution channels (id. at 5:20–
21), including an embodiment using “only public key cryptography”
(see, e.g., id. at 5:37–40, 6:9–36, Figs. 2–3) and an embodiment using both
“public key and symmetric key cryptography” (see, e.g., id. at 5:41–44, 6:3–
4, 6:38–7:5, Figs. 4–5).
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Figure 1 of Arnold is reproduced below.

Figure 1 of Arnold is a block diagram depicting computer system 10
including “cryptographic system 12 comprising microprocessor 14, memory
16, and cryptographic functions 18 mounted upon . . . adapter card 20.”
Ex. 1004, 5:35–36, 5:49–51. The microprocessor, memory, and
cryptographic functions are housed within a secured area or module 22. Id.
at 5:51. Public key KPU is installed in the adapter card 20. Id. at 5:52.
Cryptographic system 12 includes the public key algorithm (e.g., RSA). Id.
at 5:52–53.
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Figure 2 of Arnold is reproduced below.

Figure 2 of Arnold is a block diagram of an embodiment employing public
key cryptography for the secure distribution of software and data.
See Ex. 1004, 5:37–38; see also id. at 5:41–52 (stating Figure 4 depicts a
block diagram of an embodiment employing both public key cryptography
and symmetric key cryptography), Fig. 4. As shown in Figure 2, data (D)
may be encrypted by public key cryptography system 24 using private key
KPR to generate pke(D). Id. at 5:56–58, Fig. 2; see also id. at Fig. 4 (also
depicting public key cryptographic system 24). A digital signature on data
(D) called dsig(D) may also be computed using digital signature generator
26. Id. at 6:1–2, Figs. 2, 4. Encrypted data pke(D) and digital signature
dsig(D) are sent to the user, who loads the data into the secured area of
adapter card 20. Id. at 6:25–27; 6:49–52. In the embodiment using only
public key cryptography, the adapter decrypts the data using public key
KPU, recovering clear data (D) and verifies the digital signature. Id. at
6:28–29. In the embodiment using public key and symmetric key
cryptography, public key KPU is used to decrypt the symmetric key using
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the public key algorithm and the recovered symmetric key is used to decrypt
the data using the symmetric key algorithm. Id. at 6:52–54; see also id. at
6:2–4 (stating “the digital signature is verified before the data is accepted by
digital signature verifier 28, which can be a component of cryptographic
function 18” and that, preferably, “cryptographic function 18 include both a
public key cryptographic system 18a and a symmetric cryptographic system
18b”). A verified digital signature proves, inter alia, that the data has not
been altered since its creation. Id. at 6:4–6.
Figure 3 of Arnold is reproduced below.

Figure 3 of Arnold depicts a flowchart of an embodiment employing public
key cryptography for the secure distribution of software, software updates,
and configuration data. Ex. 1004, 5:39–40; see also id. at 6:9–36
(describing the embodiment shown in Figure 3).
As shown in Figure 3, the manufacturer generates data (D) to be
loaded into an adapter card and computes a digital signature (dsig(D)) on
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data (D) using private key KPR (steps 100, 110). Ex. 1004, 6:13, 6:18–20.
The manufacturer already possesses private key KPR, and the corresponding
public key (public key KPU) may be embedded in the adapter card or
supplied externally. Id. at 6:14–16. According to Arnold, public key KPU
does not need to be kept secret in order to maintain integrity of the loaded
data. Id. at 6:16–17; see also id. at 6:33–34 (“Only the private key KPR
needs to be kept secret. The public key KPU is present in every copy of the
device, and there is no security exposure if its value is divulged.”). Data (D)
may be encrypted using a private key algorithm with private key KPR,
yielding pke(D) (step 120). Id. at 6:22–24. The manufacturer may send
encrypted data pke(D) and digital signature dsig(D) to the adapter card user
(step 130), who may receive this information and load it into the secured
area of the adapter card (step 140). Id. at 6:25–27. The adapter card may
then decrypt encrypted data pke(D) using public key KPU and recover clear
data D (step 150). Id. at 6:28. Digital signature dsig(D) may be verified
using the same key (step 160). Id. at 6:28–29. Once data pke(D) has been
decrypted and signature dsig(D) has been verified, clear data (D) may be
applied to the nonvolatile memory in the adapter card (step 180) or
otherwise discarded (step 170). Id. at 6:30–32.
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Figure 5 of Arnold is reproduced below.

Figure 5 of Arnold depicts a flowchart of an embodiment employing both
public key cryptography and symmetric key cryptography. Ex. 1004, 5:43–
44; see also id. at 6:38–7:5 (describing the embodiment shown in Figure 5).
In step 260 of Figure 5, encrypted data (including encrypted data pke(D),
encrypted digital signature dsig(D), and an encrypted random symmetric
algorithm key) is received at the user site where the adapter cards are
installed and the data is loaded into the “secured area of the card, which
contains . . . public key KPU.” Id. at 6:44–52. The public key is used to
decrypt the symmetric key and the recovered symmetric key is used to
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decrypt the data using the symmetric key algorithm (steps 270, 280). Id. at
6:51–54. The digital signature is verified using KPU (step 290). Id. at 6:55.
If the signature verifies, then both data D and key KS (the random
symmetric algorithm key) were valid and the data is loaded into the adapter
card and enabled for use. Id. at 6:55–57. All cryptographic calculations are
preferably performed inside the secured area of the adapter card so there is
no threat of data manipulation while the data is recovered and verified. Id.
at 6:57–59.
Arnold also describes, in its “Description of Related Art” section, “the
IBM 4755 Cryptographic Adapter” as “a device which includes a
microprocessor, memory, and programming logic mounted on a printed
circuit board” with “[f]unctions . . . housed within a tamper-resistant
module, or secured area, for protection.” Ex. 1004, 4:18–21.
2. Overview of Chang
Chang, titled “Method and Apparatus for Enhancing Software
Security and Distributing Software,” generally relates to using public key
encryption techniques for achieving enhanced security and product
authentication in the distribution of software. Ex. 1005, code (54), 1:6–11,
3:15–17. Chang describes the problem of “authenticating that [the] software
distributed by a manufacturer is a legitimate copy of an authorized software
release, and that the software contains only the original manufacturer’s code
without tampering.” Id. at 3:2–5. To address this problem, Chang describes
using a “software passport,” which includes the digital signature of the
application writer and manufacturer. Id. at 3:7–8. Chang describes that
“[t]he software passport provides the basis of a trust model and allows
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computer users to identify and determine the genuineness of a software
product based on the information contained in its passport.” Id. at 6:34–38.
Figure 3 of Chang is reproduced below.

Figure 3 of Chang depicts a software passport. Ex. 1005, 4:51–54, 6:42–45.
As shown in Figure 3, the software passport may include, among other
things, the application writer’s public key, the software code body including
executable application code distributed to the user an application writer’s
license, and the platform builder’s digital signature. Id. at 6:48–63, Fig. 3.
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Figures 6a and 6b of Chang are reproduced below.

Figures 6a and 6b of Chang are flowcharts for verifying that a valid software
license exists, and that the application writer’s digital signature is valid, prior
to permitting execution of a computer program. Ex. 1005, 4:59–63. As
shown in Figure 6a, after determining that the software has a passport and an
application writer’s license, the platform may extract the public key
embedded in the platform to verify that the passport’s license is valid. Id. at
9:27–31. The license validation process may be accomplished by
recomputing the message digest of the application license in the passport,
recovering the original message digest (by decrypting the issuer’s (platform
builder’s) digital signature using the platform builder’s public key), and
comparing the old digest with the newly computed digest. Id. at 9:34–43.
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The system determines that the passport contains a valid application writer’s
license if the two message digests are the same. Id. at 9:44–45.
As shown in Figure 6b, the system also may verify that the application
writer’s digital signature is valid. Ex. 1005, 9:53–55. The signature
validation process may be accomplished by recomputing the message digest
of the passport, recovering the original message digest (by decrypting the
application writer’s digital signature using the application writer’s public
key embedded in the application writer’s license within the passport), and
comparing the old digest with the newly computed digest. Id. at 9:59–67.
The system determines that the signature is valid if the two message digests
are the same. Id. at 10:1–2. After verifying that the license and signature
are valid, the operating system (OS) may obtain an additional approval to
run the code, and the code may be executed. Id. at 10:15–22, Fig. 6b;
see also id. at 4:29–40.
Figure 5 of Chang is reproduced below.

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Figure 5 of Chang depicts the components of software passport 50 being
issued by the platform builder, compiled by compiler 68, and then provided
to (and received by) an end user of the OS running on the platform.
Ex. 1005, 4:57–58, 8:55–65, 9:19–23, 10:10–11, Fig. 5; see also id. at 8:25–
32, 8:49–54, Fig. 4. The end user may be provided both the application
writer’s public key 62 as well as the platform builder’s public key 54. Id. at
9:27–28, 9:59–61.
3. Overview of Stefik
Stefik, titled “System for Controlling the Distribution and Use of
Digital Works Having Attached Usage Rights Where the Usage Rights Are
Defined by a Usage Rights Grammar,” generally relates to controlling the
use and distribution of digital works, such as software. Ex. 1006, code (54),
4:4–8. Stefik describes a system in which digital works and their attached
usage rights are stored in and transmitted between repositories. Id. at 4:40–
42.
Figure 2 of Stefik is reproduced below.

Figure 2 of Stefik is a block diagram depicting various repository types and
the repository transaction flow between them. Ex. 1006, 4:55–58, 7:49–50.
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The various repository types serve different functions but share a core set of
functionality enabling secure and trusted communications. Id. at 7:50–54.
As shown in Figure 2, repository 201, a general instance of a repository,
receives and processes access requests to digital works while in server mode,
and initiates requests to access digital works while in requester mode. Id. at
7:54–60. Repository 201 may communicate via repository transaction
protocol 205 with a plurality of other repositories, including authorization
repository 202, rendering repository 203, and master repository 204. Id. at
7:62–67. Communication with authorization repository 202 may occur
when a digital work being accessed has a condition that needs authorization.
Id. at 8:1–3. Communication with rendering repository 203 may occur in
connection with rendering a digital work. Id. at 8:10–11. And
communication with master repository 205 may occur in connection with
obtaining an identification certificate, by which a repository is identified as
“trustworthy.” Id. at 8:15–18.
Stefik describes the use of public keys by the master repository and
rendering repository as follows:
Key management and security is instrumental in the
success of a public key encryption system. In the currently
preferred embodiment, one or more master repositories
maintain the keys and create the identification certificates used
by the repositories.
Ex. 1006, 27:11–15.
[T]he master repository has special functionality for
issuing digital certificates and maintaining encryption keys.
Id. at 15:25–27.
The requester [(rendering repository)] decrypts the digital
certificate using the public key of the master repository,
recording the identity of the supplier and creator, a key for
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decrypting the software, the compatibility information, and a
tamper-checking code. (This step certifies the software.).
Id. at 42:48–53; see also id. at 43:32–34.
Stefik further describes that a repository may be embedded in a device
or enclosed in a secure housing as follows:
[T]he repository could be embedded in a “card” that is
inserted into an available slot in a computer system.
Id. at 16:59–61.
The hardware embodiment of a repository will be
enclosed in a secure housing which if compromised, may cause
the repository to be disabled.
Id. at 14:16–19, Fig. 12.
Stefik also describes repository security levels including level 4 and
above at which “[s]ensors are used to record attempts at physical and
electronic tampering” and, “[a]fter such tampering, the repository will not
perform other transactions until it has reported such tampering to a
designated server.” Ex. 1006, 16:21–38; see also id. at 8:43–50 (describing
that communications within a printer system and its printer repository are
assumed to be secure), 9:11–13 (describing a computer system having a
security boundary within which communications are assumed to be secure).
E. Anticipation by Arnold
Petitioner contends claims 9 and 29 are anticipated by Arnold. Pet.
39–57. As explained above, claims 9 and 29 are independent and recite
similar limitations, with the only difference being that claim 9 recites “load
modules” whereas claim 29 recites “executables.” Ex. 1001, 22:5–15,
24:10–21. Because of their similarities, Petitioner provides nearly identical
contentions for both these claims (compare Pet. 43–55, with Pet. 56–57) and
Patent Owner’s arguments also equally apply to both these claims (PO Resp.
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21–31). In the sections below we analyze Petitioner’s contentions with
respect to claim 9 but our analysis also equally applies to claim 29, as does
our conclusion.
1. Preamble and Limitations (a) and (b)
Claim 9 recites “A method of distinguishing between trusted and
untrusted load modules comprising: (a) receiving a load module, (b)
determining whether the load module has an associated digital signature.”
Ex. 1001, 22:5–9. Petitioner contends Arnold discloses the preamble and
limitations (a) and (b) of claim 9. Pet. 43–49. Patent Owner does not
separately dispute Petitioner’s contentions. We analyze Petitioner’s
contentions here.
Petitioner contends Arnold teaches a method of distinguishing trusted
and untrusted load modules by disclosing a method for secure distribution of
software, software updates, and configuration data. Pet. 43 (citing Arnold
(57), 2:15–17). Petitioner identifies the software, software updates, and
configuration data as the recited “load modules” because the software,
software updates, and configuration data would be “executed immediately
after the data is loaded.” Id. (citing Ex. 1004, 10:37–38). Arnold
distinguishes between trusted and untrusted load modules, according to
Petitioner, because it verifies a digital signature on the data (i.e. the software
etc.) to verify the data is genuine and comes from a valid source. Id. at 43–
44 (citing Ex. 1004, 5:14, 6:28–32, 6:55–57, Fig. 3; Ex. 1002 ¶¶ 130–133,
162).
Petitioner contends that as part of the process of distributing data
(software, software updates, etc.) to the user, Arnold computes a digital
signature on the data and sends the signature along with the data to the
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receiving device, which verifies the signature before the data is accepted.
Pet. 47–49 (citing Ex. 1004, 2:5–17, 5:12–25, 5:52–59, 6:1–6, 6:13–32,
9:56–10:38, Figs. 2, 3; Ex. 1002 ¶¶ 134–138, 140, 162). Thus, Petitioner
contends Arnold discloses “receiving a load module” and “determining
whether the load module has an associated digital signature.”
We are persuaded by Petitioner’s contentions. Generally, a preamble
does not limit a claim. Allen Eng’g Corp. v. Bartell Indus., Inc., 299 F.3d
1336, 1346 (Fed. Cir. 2002). Here, we need not decide whether the
preamble limits claim 9 because Petitioner establishes that Arnold teaches
the preamble of claim 9. Arnold discloses a system and method for the
secure distribution of software. Ex. 1004, code (57). To provide the
required security, Arnold encrypts the software and generates a digital
signature for the software. Ex. 1004, 6:44–59. The encrypted software and
the digital signature are then sent to the user. Id. When the software is
received, its digital signature is verified in order verify the origin of the data.
Id. If the signature verifies, the software is loaded into the memory of the
receiving device. Id. Dr. Chatterjee provides credible testimony that,
because Arnold verifies the digital signature before loading the software,
Arnold teaches a method of distinguishing between trusted and untrusted
load modules. Ex. 1002 ¶¶ 130–133. This evidence sufficiently supports
Petitioner’s contentions regarding the preamble and limitations (a) and (b) of
claim 9.
2. Limitation (c)
Limitation (c) of claim 9 recites “if the load module has an associated
digital signature, authenticating the digital signature using at least one public
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key secured behind a tamper resistant barrier and therefore hidden from the
user.” Ex. 1001, 22:10–13.
Petitioner contends that Arnold discloses a security adapter card with
a secure area and that this secure area is a “tamper resistant barrier” as
recited in claim 9. Pet. 49–50 (citing Ex. 1004, 5:9–13, 10:47–48; Ex. 1002
¶ 143). Petitioner contends that Arnold discloses that, when the user
receives the encrypted software and digital signature, it “loads the data and
signature into the secured area of the adapter card.” Id. at 49 (quoting Ex.
1004, 6:26–27). Petitioner further contends that Arnold’s public key is used
to verify the digital signature of Arnold’s load modules and that this public
key is contained in the secure area of the adapter card. Id. at 49–53 (citing
Ex. 1004, 3:56–57, 5:9–13, 5:52–53, 6:28–30, 6:51–59; Ex. 1002 ¶¶ 141–
144, 162). Thus, Petitioner contends Arnold discloses authenticating the
digital signature using at least one public key secured behind a tamper
resistant barrier and, therefore, hidden from the user as recited in limitation
(c).
Patent Owner contends that Arnold does not disclose that the public
key is hidden from the user, which Patent Owner interprets as requiring that
the public key have no read access. PO Resp. 21–28. Patent Owner makes
two primary arguments in this regard. First, Patent Owner argues the public
key in Arnold, in contrast to a private key, is described as not being kept
secret and, therefore, not hidden from the user. Id. at 23 (citing Ex. 1003,
6:15–17, 6:33–34, Ex. 2027 ¶¶ 67–69). Second, Patent Owner argues that
the public key is not kept in the secured area of the adapter card and,
therefore, not secured behind a tamper resistant barrier and hidden from the
user. Id. at 23–27 (citing Ex. 1004, Figs. 1, 2).
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After considering the arguments and evidence presented by both
parties, we are persuaded that Arnold discloses limitation (c) of claim 9.
Arnold discloses an adapter card with a secured area. Ex. 1004, 5:49–51
(describing that the microprocessor, memory, and cryptographic functions of
Arnold’s cryptographic system are “housed within a secured area or
module” of an adapter card); Pet. 49–50. Arnold describes the secured area
of its adapter card as an area “where data is protected from disclosure”
(Ex. 1004, 5:10) and “which is protected from physical and direct electrical
access” (Ex. 1004, 10:47–48). Pet. 49–50. These disclosures indicate that
the secured area of Arnold’s adapter card is a “tamper resistant barrier” that
prevents the data stored within from read access and, therefore, keeps the
data “hidden from the user” as recited in limitation (c). We also credit Dr.
Chatterjee’s testimony that, based on Arnold’s description of the secured
area of the adapter card, the secured area forms a tamper resistant barrier
that keeps data stored within, hidden from the user. Ex. 1002 ¶¶ 141–144
(citing Ex. 1004, 3:56–57, 5:9–12, 5:52–53, 6:13–32, 6:28–30, 6:51–52,
6:55–59).
Arnold makes clear that the “secured area of the card . . . contains the
public key KPU” (Ex. 1004, 6:51–52) and that “said public key (KPU) is
stored within said secured area.” Ex. 1004, 12:25; see also id. at 12:42
(“means for providing a public key (KPU) within said secure areas”); Pet.
Reply 9. Dr. Chatterjee’s testimony, which we determine to be credible,
also supports Petitioner’s contention that Arnold’s public key is within the
secured area of Arnold’s adapter card. Ex. 1002 ¶ 143 (“The public key is
secured behind a tamper resistant barrier and therefore hidden from the
user.”).
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The above disclosures indicate that (1) Arnold’s public key is stored
in the secure area of Arnold’s adapter card and that (2) the secure area
protects data from disclosure and prevents physical and direct electrical
access.5 Thus, we agree with Petitioner that Arnold’s public key is “secured
behind a tamper resistant barrier and therefore hidden from the user” as
recited in claim 9.
Patent Owner argues that Arnold’s disclosures that the public key
“does not need to be kept secret in order to maintain integrity of the loaded
data” and that “[o]nly the private key KPR needs to be kept secret” indicate
that the public key is not kept hidden from the user. PO Resp. 22–23
(citing Ex. 1004, 6:15–17, 6:33–34). Similarly, Patent Owner points to
Figures 1 and 2 of Arnold to argue that these figures show the public key is
not contained within the secure area of Arnold’s adapter card and therefore,
not hidden from the user. PO Resp. 26. Figures 1 and 2 of Arnold, as
annotated by Patent Owner, are reproduced below for convenience.

5 In Petitioner’s Reply Brief, Petitioner additionally relies on U.S. Patent No.
5,027,397 (“Double”) (Ex. 1015), which Petitioner argues Arnold
incorporates by reference, as disclosing a tamper resistant barrier that
prevents interrogation of data stored within and, therefore, keeps that data
hidden from the user. Pet. Reply 6 (citing Ex. 1004, 4:18–21, 1015, 3:38–
42). In reaching our conclusion that Arnold discloses limitation (c), we do
not rely on Petitioner’s contentions regarding Double for the ground based
on anticipation by Arnold.
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Id. at 25–26. Figure 1 of Arnold shown above, depicts Arnold’s computer
system with its cryptographic system enlarged and broken out. Ex. 1004,
5:35–36. Patent Owner argues that Figure 1 does not show the public key as
being contained in secured area 22 of Arnold’s adapter card 20. PO Resp.
25. Figure 2 of Arnold shown above, depicts a block diagram of an
embodiment of Arnold’s system. Ex. 1004, 5:37–38. In Figure 2, public
key KPU is shown both inside and outside the dotted line representing
Arnold’s secure card 20. Based on this depiction, Patent Owner argues the
public key is “available to adapter card 20 from outside of the adapter card”
and that Figure 2 “does not teach that the public key is restricted to the
secure area 22 of adapter card 20, or being hidden from the user.” PO Resp.
26.
Based on the totality of the disclosure of Arnold, we disagree with
Patent Owner’s arguments. Specifically, as explained above, Arnold is
explicit in disclosing that the “secured area of the card . . . contains the
public key KPU” (Ex. 1004, 6:51–52) and that “said public key (KPU) is
stored within said secured area.” Ex. 1004, 12:25; see also id. at 12:42
(“means for providing a public key (KPU) within said secure areas”).
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We agree with Petitioner that Arnold’s disclosure that the public key does
not need to be kept secret or that only the private key needs to be kept secret
(Ex. 1004, 6:15–17, 6:33–34) describes the general nature of public and
private keys but does not describe the more specific embodiments disclosed
in Arnold where the public key is expressly described as being within the
secured area of the adapter card. Pet. Reply 7–8. In other words, we
determine that the express disclosure that the secured area contains the
public key and that the public key is stored within said secured area more
specifically describes Arnold’s relied upon embodiments. The general
description of public keys in Arnold that Patent Owner points to do not
undermine these express disclosures.
Patent Owner takes issue with Arnold’s express disclosure that “said
public key (KPU) is stored within said secured area” found in dependent
claim 6 of Arnold because, as Patent Owner argues, it “only describes
storing a public key in secure memory to decrypt encrypted data . . . not to
authenticate a digital signature.” PO Sur-reply 12. First, this argument does
not account for the description in Arnold that the “secured area of the
card . . . contains the public key KPU” and that the KPU is used to verify the
digital signature, which Petitioner also relies on to show that the public key
is contained in the secure area of the adapter card. Pet. 52 (citing Ex. 1004,
6:51–59). Second, we disagree that Arnold’s disclosure in dependent claim
6 is limited only to decrypting encrypted data and does not apply to
authenticating a digital signature. Dependent claim 6 of Arnold depends
from independent claim 1. Ex. 1004, 12:24–25. Claim 1 of Arnold is
directed to “[a] method of transferring data into a secured area” which refers
to Arnold’s method for secure storage and distribution of data in general. Id.
at 11:50–55. This method “us[es] digital signature[s].” Id. at code (54).
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Moreover, every embodiment of Arnold uses digital signatures to verify the
data being loaded. See id. at Figs. 2–5. Thus, we determine that the public
key referred to in Arnold’s dependent claim 6 is not limited to decrypting the
distributed data but is also applies to verification using digital signatures.
Patent Owner argues that Figure 1 does not show the public key to be
contained within the secure area of the adapter card. PO Resp. 25. But
Figure 1 does not show the public key at all, whether within or outside the
secure area. As such, Figure 1 cannot be taken to indicate the location of the
public key one way or another. Figure 2 is a flow diagram that indicates the
public key can be provided from within or from outside the card. As with
the general description of public keys, Figure 2 does not specifically
describe the relied upon embodiments (e.g. the “public key and symmetric
key cryptography” embodiment) of Arnold. We determine that, when taken
in light of Arnold’s explicit disclosures that the public key is contained in
the secure area of the adapter card, Figure 2 is best interpreted as showing
that the public key is provided from within the card.
For the aforementioned reasons, we agree with Petitioner that Arnold
discloses limitation (c) of claim 9.
3. Limitation (d)
Limitation (d) recites “conditionally executing the load module
based at least in part on the results of authenticating step (c).” Ex. 1001,
22:14–15. Petitioner relies on various passages from Arnold that indicate
that Arnold’s data (e.g. software) is loaded if the associated signature is
verified. Pet. 53–55 (citing Ex. 1004, 6:28–32, 6:55–59, 9:57–10:25, 10:37–
38, 11:16; Ex. 1002 ¶¶ 146–149). Patent Owner does not separately dispute
Petitioner’s contentions with regard to limitation (d).
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We are persuaded by Petitioner’s arguments that Arnold discloses
limitation (d). For example, Arnold discloses that, “[i]f the signature
verifies, the data is genuine and it can only have been created by the
manufacturer, who holds the private key KPR. Once the data has been
decrypted and its validity has been determined, the data is applied to the
nonvolatile memory in the adapter card, step 180; otherwise, the information
is discarded, step 170.” Ex. 1004, 6:28–32. Arnold further discloses that,
“[i]f the signature verifies, . . . the data is loaded into the nonvolatile
memory on the adapter card and enabled for use, step 310.” Id. at 6:55–59.
For the reasons provided by Petitioner in its Petition (Pet. 53–55), we
are persuaded Arnold discloses limitation (d).
4. Conclusion as to Anticipation over Arnold
For the reasons explained above, we determine that Petitioner has
shown that Arnold discloses each limitation of claim 9 and claim 29 of the
ʼ721 patent. Accordingly, we conclude that Petitioner has shown by a
preponderance of the evidence the unpatentability of claims 9 and 29 as
anticipated by Arnold.
F. Obviousness over Arnold
As explained above, Petitioner contends that Arnold anticipates
claims 9 and 29, but nevertheless presents an alternative ground, arguing that
even if Arnold does not explicitly meet limitation (c) (“a tamper resistant
barrier and therefore hidden from the user”), a POSITA would have been
motivated to apply the teachings of the related prior art disclosed in Arnold,
including Double, to the secured area of Arnold’s adapter card so that this
secured area would be tamper resistant and would keep the data stored
within, “hidden from the user.” Pet. 57–59. Petitioner argues that Arnold
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“expressly provides, it was well-known and desirable to house cryptographic
functions, including keys, within a tamper-resistant module.” Pet. 58 (citing
Ex. 1004, 4:16–21, 3:21–24). According to Petitioner, such a tamper-
resistant module is disclosed in Double, which is incorporated by reference
in Arnold. Id. (citing Ex. 1004, 4:16–21; Ex. 1015, 3:38–42; Ex. 1002
¶¶ 164–165).
As before, Patent Owner argues that Arnold’s public key is described
as being public and not hidden from the user, and that Arnold’s discussions
of securing the key in tamper-resistant modules apply only to private keys.
PO Resp. 28–29 (citing Ex. 2027 ¶¶ 83–85); PO Sur-reply 11. Thus,
according to Patent Owner, these portions of Arnold cannot be used as
motivation to combine with the other cited references to provide a tamper
resistant barrier that keeps the public key hidden from the user. PO Resp.
30. With respect to the embodiment in which Arnold explicitly discloses
that the “secured area of the card . . . contains the public key KPU,” Patent
Owner argues that this embodiment does not disclose securing the public
key at all times, but rather is more concerned with keeping the private key
KS secret. Id. at 30–31 (citing Ex. 2027 ¶¶ 91–93).
Having considered the arguments and evidence presented by both
parties, we are persuaded by Petitioner that Arnold along with its
incorporated prior art, Double, teach limitation (c) of claim 9.6 Double
discloses key store 14 that stores encryption keys, and a scheme for
detecting and “preventing unauthorized interrogation” of the stored
encryption keys in the key store. Ex. 1015, 3:38–42. We agree with

6 As explained above, we have already determined that Arnold discloses the
preamble and limitations (a) (b) and (d) of claim 9. See supra Section II.E.1
and 3.
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Petitioner that, by preventing interrogation of stored keys, Double teaches a
tamper-resistant barrier that prevents read access and, therefore, keeps keys
hidden from the user. When the teachings of Double’s key store 14 are
applied to the secured area of Arnold’s adapter card 20, which Arnold
discloses as containing and storing the public key, we agree with Petitioner
that Arnold, and the incorporated disclosure of Double, teach a “public key
secured behind a tamper resistant barrier and therefore hidden from the
user.”
We disagree with Patent Owner’s argument that Arnold’s discussion
of the desirability of a tamper-resistant barrier (Ex. 1004, 4:18–21) and its
discussion of keeping cryptographic functions and data secure (Ex. 1004,
3:21–24) would not apply to Arnold’s public key. As explained above in
our analysis of anticipation by Arnold, Arnold explicitly discloses that the
public key is contained and stored within the secured area of its adapter card
20. See supra §§ II.E.2 (citing Ex. 1004, 1004, 6:51–52, 12:25, 12:42).
Thus, a POSITA would have been motivated to secure the public key of
Arnold just as they would have been motivated to secure other data stored in
the secured area of Arnold’s adapter card 20.
1. Objective Indicia of NonObviousness
In its Response, Patent Owner contends that there is evidence of long-
felt need, failure of others, industry praise, commercial success, and copying
which should be considered as objective indicia of nonobviousness.
PO Resp. 42–45.
For us to give substantial weight to objective indicia of obviousness or
nonobviousness, a proponent must establish a nexus between the evidence
and the merits of the claimed invention. ClassCo, Inc., v. Apple, Inc., 838
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F.3d 1214, 1220 (Fed. Cir. 2016). “[T]here is no nexus unless the evidence
presented is ‘reasonably commensurate with the scope of the claims.’” Id.
(quoting Rambus Inc. v. Rea, 731 F.3d 1248, 1257 (Fed. Cir. 2013)).
A patentee is entitled to a presumption of nexus “when the patentee
shows that the asserted objective evidence is tied to a specific product and
that product ‘embodies the claimed features, and is coextensive with them.’”
Fox Factory, Inc. v. SRAM, LLC, 944 F.3d 1366, 1373 (Fed. Cir. 2019)
(quoting Polaris Indus., Inc. v. Arctic Cat, Inc., 882 F.3d 1056, 1072 (Fed.
Cir. 2018)). But as Petitioner correctly argues (Pet. Reply 23–25), a
presumption of nexus is inappropriate here because Patent Owner does not
provide an analysis demonstrating that its products are coextensive (or
nearly coextensive) with the challenged claim. See Lectrosonics, Inc. v.
Zaxcom, Inc., IPR2018-01129, Paper 33 at 33 (PTAB Jan. 24, 2020).
But even without the presumption, Patent Owner “is still afforded an
opportunity to prove nexus by showing that the evidence of secondary
considerations is the ‘direct result of the unique characteristics of the
claimed invention.’” Fox Factory, 944 F.3d at 1373–74 (quoting In re
Huang, 100 F.3d 135, 140 (Fed. Cir. 1996)). Also, the nexus must be “to
some aspect of the claim not already in the prior art.” In re Kao, 639 F.3d
1057, 1069 (Fed. Cir. 2011) (emphasis added). “Ultimately, the fact finder
must weigh the [objective indicia] evidence presented in the context of
whether the claimed invention as a whole would have been obvious to a
skilled artisan.” Lectrosonics, IPR2018-01129, Paper 33 at 33 (citing WBIP,
LLC v. Kohler Co., 829 F.3d 1317, 1331–32 (Fed. Cir. 2016)).
As we discuss below, we find that Patent Owner has not shown a
nexus between the claimed invention and long-felt need, failure of others,
industry praise, commercial success, or copying. Moreover, in addition to
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this proceeding, Patent Owner presents nearly the same arguments and
evidence with respect to objective indicia of nonobviousness in at least four
other proceedings involving different patents. See Dolby Laboratories, Inc.
v. Intertrust Techs. Corp., IPR2020-00661, Paper 17 at 63–68 (PTAB Jan.
21, 2021) (Patent Owner Response); Dolby Laboratories, Inc. v. Intertrust
Techs. Corp., IPR2020-00662, Paper 17 at 60–65 (PTAB Jan. 21, 2021)
(Patent Owner Response); Dolby Laboratories, Inc. v. Intertrust Techs.
Corp., IPR2020-00664, Paper 15 at 63–66 (PTAB Mar. 2, 2021) (Patent
Owner Response); Dolby Laboratories, Inc. v. Intertrust Techs. Corp.,
IPR2020-00665, Paper 19 at 62–66 (PTAB June 16, 2021) (Patent Owner
Response). Patent Owner, however, does not explain adequately how the
same evidence of objective indicia of nonobviousness can be attributable to
each particular claimed invention. See Fox Factory, 944 F.3d at 1378 (“The
same evidence of secondary considerations cannot be presumed to be
attributable to two different combinations of features. In such situations, the
patentee retains the burden of proving the degree to which evidence of
secondary considerations tied to a product is attributable to a particular
claimed invention.” (citation omitted)).
a) Long-Felt Need and Failure of Others
In order to show a long-felt but unmet need for the claimed invention,
the objective evidence must show that the need was a persistent one that was
recognized by those of ordinary skill in the art at the time of the invention.
In re Gershon, 372 F.2d 535, 538 (CCPA 1967). As evidence of long-felt
need and failure of others, Patent Owner submits three articles from the Wall
Street Journal which, according to Patent Owner, suggest a need for a way
to distribute digital content in a secure manner that would “(1) ensure the
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digital content would only be used in an authorized manner, (2) ensure that
the digital content creator would be compensated for use of the digital
content, and (3) allow for such distribution to client devices that were not
under the control of the distributor.” PO Resp. 42–43 (citing Ex. 2030, 1;
Ex. 2031, 1; Ex. 2032, 1). Patent Owner also submits another article from
the Wall Street Journal, and an article from the New York Times, describing
work by Xerox PARC, IBM, Microsoft, and other companies in the area of
digital rights management. Id. at 43 (citing Ex. 2033, 3; Ex. 2034, 1).
Patent Owner contends that “most, if not all, systems developed by
others were either not commercially successful, were not adopted by digital
content industries, copied the claimed invention or have been licensed under
the claimed invention.” PO Resp. 43. But Patent Owner does not cite any
evidence supporting this argument.
We assign this evidence little weight, because Patent Owner has not
identified anything in the cited articles that ascribes any long-felt need to the
merits of the claimed invention of the ’721 patent, and has not pointed to any
evidence that others had failed to achieve a solution to any technical
problem for which the invention of ʼ721 patent is also a solution.
b) Significance Recognized by the Industry
As evidence of industry recognition, Patent Owner submits an article
published in Fortune. PO Resp. 44 (citing Ex. 2035). Patent Owner argues
that the article praises Patent Owner’s technology for “wrap[ping] the file in
a secure digital container and tag[ging] it with rules describing how it could
be used,” and where, “[t]o play or read the . . . file, recipients would need
special software or hardware that could be trusted by the content originator
to enforce the rules.” Id. (alterations and omission in original) (emphasis
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omitted) (quoting Ex. 2035, 2). According to Patent Owner, “the use of
special software or hardware to govern access to digital content is the thrust
of the subject claims of the ʼ721 patent.” Id. (citing Ex. 1001, 4:61–7:28).
In its Reply, Petitioner contends the Fortune article merely provides a
high level summary of Patent Owner’s technology. Pet. Reply 24.
Petitioner argues that the mention of a “‘secure digital container’ and ‘rules’
in the article has nothing to do with the subject matter in claims 9 and 29
that is directed to a method of ‘distinguishing between trusted and untrusted
load modules.’” Pet. Reply 24 (citing Ex. 2035, 2).
We determine that the Fortune article fails to provide a nexus to the
claimed invention. We agree with Petitioner that the Fortune article
provides only a high level summary of Patent Owner’s technology and that
the mention of a “secure digital container” and “rules” have a tenuous
connection with the claimed subject matter of the ʼ721 patent, which does
not mention a “secure digital container” or “rules” that apply to such a
container.
Thus, we find that Patent Owner has not shown that there is a nexus
between the evidence of industry recognition and the merits of the claimed
invention. Absent a nexus, we assign little weight to the evidence of
industry praise.
c) Commercial Success and Copying
As evidence of commercial success and copying, Patent Owner argues
that over two dozen companies have licensed the claimed invention, and that
Patent Owner “has received more than $1 billion in patent licensing revenue
in return for granting licensees the right to practice the claimed invention
and [Patent Owner’s] remaining patent portfolio.” PO Resp. 45.
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But Patent Owner does not cite any evidence to support its contention,
such as the mentioned licenses themselves, or any testimony by someone
who was familiar with the circumstances of the licenses to Patent Owner’s
portfolio. Absent such evidence, we cannot assess whether the licenses have
any nexus to the limitations of the challenged claims. Thus, we assign little
weight to Patent Owner unsupported arguments on commercial success and
copying.
2. Conclusion as to Obviousness over Arnold
For the reasons explained above we give little weight to Patent
Owner’s evidence of nonobviousness. On the other hand, based on the
arguments and evidence presented in the Petition, we determine that
Petitioner has shown that Arnold along with Double, incorporated by
reference in Arnold, teach the limitations of claims 9 and 29 of the ʼ721
patent. Weighing all of the evidence of obviousness and nonobviousness,
we conclude that Petitioner has shown by a preponderance of the evidence
the unpatentability of claims 9 and 29 as obvious over Arnold.
G. Obviousness over Chang and Stefik
Petitioner contends the combination of Chang and Stefik teaches the
limitations of claims 9 and 29. Pet. 59–80. As before, Petitioner’s
contentions regarding claims 9 and 29 are nearly identical (compare Pet. 65–
79, with Pet. 79–80), as are Patent Owner’s arguments against Petitioner’s
contentions for these two claims (PO Resp. 30–42).
1. Combination of Chang and Stefik
Petitioner relies on Chang to teach most of the limitations of claims 9
and 29, but relies on Stefik primarily to teach a public key stored behind a
tamper resistant barrier (i.e. Stefik’s master repository). Pet. 64, 75 (citing
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Ex. 1006, 14:16–18, 27:11–15, 42:30–60). Petitioner argues that a POSITA
would have been motivated to apply Stefik’s teaching of storing public keys
behind a tamper resistant barrier in implementing Chang’s method of
distributing software where a public key is stored on Chang’s hardware
platform. Id. at 64. A POSITA would do so because a tamper resistant
barrier would enhance security ensuring that the keys are safeguarded. Id.
As support for its proposed motivation to combine, Petitioner relies on
Stefik’s teaching that “[k]ey management and security is instrumental in the
success of a public key encryption system.” Id. (quoting Ex. 1006, 27:11–
15). According to Petitioner, combining Stefik’s tamper resistant barrier
with Chang would further Chang’s goal of “allow[ing] only authorized code
to be executed” on its platform. Id. (citing Ex. 1005, 8:55–59; Ex. 1002
¶ 175).
Patent Owner argues that it would not have been obvious to combine
Chang and Stefik. PO Resp. 34–42. Specifically, Patent Owner argues that
Stefik involves “two-way communications” and, thus, it is important for
Stefik to prevent access to keys by third parties. Id. at 34–35 (citing
Ex. 1006, 27:2–28:7). Chang, on the other hand, involves only one-way
communication from a software distributor to a user of the software (but not
from the user to the software distributor); thus, according to Patent Owner,
keeping the public key hidden would be of no benefit because there are no
encrypted communications from the user to the software publisher. Id. at
35–36 (citing Ex. 2027 ¶¶ 105–112). Patent Owner also argues Stefik’s
tamper resistant barrier does not keep keys hidden from the user and, thus, a
POSITA would not have been motivated to combine Stefik with Chang for
that purpose. Id. at 36–39 (citing Ex. 2027 ¶¶ 113–115). Furthermore,
Patent Owner argues that Petitioner’s motivation of enhancing security is a
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general motivation that does not provide a specific reason to combine Stefik
with Chang in the way argued by Petitioner. Id. at 37. According to Patent
Owner, Petitioner’s allegations are conclusory and tainted by impermissible
hindsight reconstruction. Id. at 38–42.
Petitioner responds that that alleged difference between one-way and
two-way communications of Chang and Stefik, respectively, are irrelevant to
their asserted obviousness ground, which only relies on Stefik’s teaching of
securing keys behind a tamper resistant barrier. Pet. Reply 18.
Additionally, Petitioner argues Chang’s disclosure that platform producers
often desire to allow only authorized code on their platform would have
motivated a POSITA to secure Chang’s public key behind a tamper resistant
barrier “to prevent a user from replacing the key.” Id. at 19 (citing Ex. 1005,
8:55–59).
Having considered the evidence and arguments from both parties, we
do not agree with Petitioner that it would have been obvious to combine
Stefik’s tamper resistant barrier with Chang. Petitioner argues that a tamper
resistant barrier would enhance security and would further Chang’s goal of
allowing only authorized code to be executed on its platform. Pet. 64 (citing
Ex. 1005, 8:55–59; Ex. 1006, 27:11–15). We agree with Patent Owner that
this reason to combine is too general and conclusory to explain how the
specific modification of securing Chang’s public keys behind a tamper
resistant barrier would have provided a relevant benefit to the combination
beyond Chang’s own secure distribution system that provides security,
without placing the public key behind a tamper resistant barrier.
We determine that such a generalized and conclusory reason for combining
Chang and Stefik is insufficient. Magnum, 829 F.3d at 1380 (“To satisfy its
burden of proving obviousness, a petitioner cannot employ mere conclusory
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statements. The petitioner must instead articulate specific reasoning, based
on evidence of record, to support the legal conclusion of obviousness.”).
Specifically, Chang discloses that platform producers desire to allow only
authorized code to be executed on their platform. Ex. 1005, 8:55–59. This
is done by identifying the software that will execute on their platform. Id. at
8:60–62. Chang provides a solution to this problem by using software
passports that include digital signatures. Id. at 8:65–9:48. Chang’s solution
involves using a public key which is not kept behind a tamper resistant
barrier. Id. Thus, Petitioner’s proposed motivation to combine to “enhance
security” (Pet. 64) and to allow only authorized code to be executed on a
platform does not explain why the public key would have to be kept behind
a tamper resistant barrier.
In response to the argument that its motivation is too conclusory,
Petitioner further explains that its proposed motivation to combine (a
platform producer’s desire to allow only authorized code on their platforms)
would have motivated a POSITA to secure Chang’s public key behind a
tamper resistant barrier to prevent a user from replacing the key. Pet. Reply
19 (citing Ex. 1005, 8:55–59). We agree with Patent Owner that this
motivation suffers from hindsight bias as it is the same motivation disclosed
in the ʼ721 patent itself for securing public keys behind a tamper resistant
barrier. Ex. 1001, 14:23–28 (“In addition, maintaining the ‘public’ key
within a tamper resistant environment forecloses the significant threat that
the owner of protected processing environment 108 may himself attack the
environment.”). Petitioner does not provide evidence that the motivation of
preventing the user themselves from replacing the public key was a known
problem in the industry or that it stems from either Chang or Stefik. Without
such evidence, we conclude that Petitioner’s articulated reason for
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combining Chang and Stefik is tainted by impermissible hindsight
reconstruction. Sci. Plastic Prod., Inc. v. Biotage AB, 766 F.3d 1355, 1359
(Fed. Cir. 2014) (“The pertinence of the reference as a source of solution to
the inventor’s problem must be recognizable with the foresight of a person
of ordinary skill, not with the hindsight of the inventor’s successful
achievement.”).
Because we determine Petitioner has not provided a sufficient
motivation to combine Chang with Stefik we need not further analyze its
contentions regarding how this proposed combination teaches all the
limitations of claims 9 and 29.
2. Conclusion as to Obviousness over Chang and Stefik
For the reasons stated above, Petitioner’s arguments and evidence
that a POSITA would have combined Chang and Stefik in the manner
alleged by Petitioner are not sufficient to justify a conclusion of
obviousness. Accordingly, we conclude Petitioner has not shown by a
preponderance of the evidence that claims 9 and 29 would have been
obvious over Chang and Stefik.
III. CONCLUSION7
Weighing all of the evidence of obviousness and nonobviousness
together, including the content of the prior art, the differences between the

7 Should Patent Owner wish to pursue amendment of the challenged claims
in a reissue or reexamination proceeding subsequent to the issuance of this
decision, we draw Patent Owner’s attention to the April 2019 Notice
Regarding Options for Amendments by Patent Owner Through Reissue or
Reexamination During a Pending AIA Trial Proceeding. See 84 Fed. Reg.
16,654 (Apr. 22, 2019). If Patent Owner chooses to file a reissue application
or a request for reexamination of the challenged patent, we remind Patent
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prior art teachings and the claim limitations, and the objective indicia of
nonobviousness, we determine that Petitioner has shown by a preponderance
of the evidence that claims 9 and 29 are anticipated by Arnold and also
would have been obvious over Arnold. We, however, determine that
Petitioner has not shown by a preponderance of the evidence that claims 9
and 29 would have been obvious over Chang and Stefik.
In summary:

IV. ORDER
In consideration of the foregoing, it is hereby:
ORDERED claims 9 and 29 of the ʼ721 patent are held to be
unpatentable; and
FURTHER ORDERED that, because this is a Final Written Decision,
the parties to the proceeding seeking judicial review of the decision must
comply with the notice and service requirements of 37 C.F.R. § 90.2.

Owner of its continuing obligation to notify the Board of any such related
matters in updated mandatory notices. See 37 C.F.R. §§ 42.8(a)(3), (b)(2).
Claims
35
U.S.C. §
Reference(s)/
Basis
Claims
Shown
Unpatentable
Claims
Not Shown
Unpatentable
9, 29 102 Arnold 9, 29
9, 29 103 Arnold 9, 29
9, 29 103 Chang, Stefik 9, 29
Overall
Outcome
9, 29
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FOR PETITIONER:
Scott A. McKeown
Mark Rowland
Keyna Chow
ROPES & GRAY LLP
scott.mckeown@ropesgray.com
mark.rowland@ropesgray.com
keyna.chow@ropesgray.com
Leslie Spencer
DESMARAIS LLP
lspencer@desmaraisllp.com

FOR PATENT OWNER:
Christopher A. Mathews
Razmig Messerian
Tigran Guledjian
Scott Florance
QUINN EMANUEL URQUHART & SULLIVAN LLP
chrismathews@quinnemanuel.com
razmesserian@quinnemanuel.com
tigranguledjian@quinnemanuel.com
scottflorance@quinnemanuel.com