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`UNITED STATES PATENT AND TRADEMARK OFFICE
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`BEFORE THE PATENT TRIAL AND APPEAL BOARD
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`NETAPP, INC., LENOVO (UNITED STATES) INC., and EMC CORP.,
`Petitioners
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`v.
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`INTELLECTUAL VENTURES II LLC
`Patent Owner
`____________________
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`IPR2017-00467
`Patent 6,968,459
`____________________
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`PATENT OWNER INTELLECTUAL VENTURES II LLC’S
`PRELIMINARY RESPONSE TO PETITION
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`Mail Stop PATENT BOARD
`Patent Trial and Appeal Board
`U.S. Patent & Trademark Office
`P.O. Box 1450
`Alexandria, VA 22313-1450
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`I.
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`II.
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`IPR2017-00467
`Patent No. 6,968,459
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`TABLE OF CONTENTS
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`Introduction. ..................................................................................................... 1
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`The ’459 patent solved the important problem of preventing authorized users
`from copying sensitive data to unsecured removable storage devices. ........... 2
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`III. Claim construction. .......................................................................................... 5
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`IV. The Board should exercise its discretion under 35 U.S.C. § 325(d) to deny
`the Petition because it presents a substantially similar argument that the
`Board denied in a previous IPR petition against the ’388 patent. ................... 6
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`V. Ground 1: The Board should deny institution because Petitioners have not
`established a reasonable likelihood that the combination of Blakley and
`Bramhill renders claims 15, 18, 24, and 25 obvious. ...................................... 8
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`A. Overview of Blakley. ............................................................................ 8
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`B.
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`C.
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`Overview of Bramhill. .........................................................................12
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`Petitioners have not established a reasonable likelihood that the
`combination of Blakley and Bramhill renders independent claim 15
`obvious. ...............................................................................................13
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`1.
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`2.
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`Petitioners have not established a reasonable likelihood of
`showing that the combination discloses the “sensing” element
`of claim 15. ...............................................................................13
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`Petitioners have not established a reasonable likelihood of
`showing that the combination discloses “providing restricted-
`access to the storage device” as recited in claim 15. ................23
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`D.
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`Petitioners have not established a reasonable likelihood that the
`combination of Blakley and Bramhill renders claims 18, 24, and 25
`obvious. ...............................................................................................27
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`VI. Ground 2: The Board should deny institution because Petitioners have not
`established a reasonable likelihood that the combination of Uchida and
`Bramhill renders claims 15, 18, 24, and 25 obvious. ....................................28
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`IPR2017-00467
`Patent No. 6,968,459
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`A.
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`B.
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`Petitioners have not established a reasonable likelihood that the
`combination of Uchida and Bramhill renders independent claim 15
`obvious. ...............................................................................................28
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`Petitioners have not established a reasonable likelihood that the
`combination of Uchida and Bramhill renders claims 18, 24, and 25
`obvious. ...............................................................................................32
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`VII. The Board should deny at least one of the grounds due to redundancy. .......35
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`VIII. Conclusion. ....................................................................................................36
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`Table of Authorities
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`IPR2017-00467
`Patent No. 6,968,459
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`Cases
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`Corning Inc. v. DSM IP Assets B.V.,
`IPR2013-00048, Paper 94 (PTAB May 9, 2014) .................................................... 22
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`Conopco dba Unilever v. Procter & Gamble Co.,
`IPR2014-00628, Paper 21 (PTAB October 20, 2014) ............................................... 6
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`Conopco, Inc. v. Procter & Gamble Co.,
`IPR2013-00505, Paper 9 (PTAB Feb. 12, 2014) ..................................................... 35
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`D-Link Systems, Inc. v. Chrimar Systems, Inc.,
`IPR2016-01426, Paper 13 (PTAB Jan. 12, 2017) ................................................... 21
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`In re Gordon,
`733 F.2d 900 (Fed. Cir. 1984) .................................................................................. 16
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`In re Nuvasive,
`842 F.3d 1376 (Fed. Cir. 2016)................................................................................ 21
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`KSR Int’l Co. v. Teleflex Inc.,
`550 U.S. 398 (2007) ........................................................................................... 19, 20
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`Los Angeles Biomedical Research Inst. at Harbor-UCLA Med. Ctr. v.
`Eli Lilly & Co.,
`__ F.3d __, 2017 WL 765812 (Fed. Cir. February 28, 2017) ................................. 20
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`Phillips v. AWH Corp.,
`415 F.3d 1303 (Fed. Cir. 2005).................................................................................. 5
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`Unified Patents v. Intellectual Ventures II LLC,
`IPR2016-01404, Paper 9 (PTAB January 11, 2017) ................................................. 6
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`Vivid Techs. v. Amer. Science,
`200 F.3d 795 (Fed. Cir. 2000) .................................................................................... 5
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`Statute
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`IPR2017-00467
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`IPR2017-00467
`Patent No. 6,968,459
`Patent No. 6,968,459
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`Statute
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`35 U.S.C. § 325(d) ................................................................................................ 6, 8
`35 U.S.C. § 325(d) .............................................................................................. ..6, 8
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`I.
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`Introduction.
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`IPR2017-00467
`Patent No. 6,968,459
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`The Board should not institute trial on either of the grounds asserted by
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`Petitioners because both grounds contain fundamental deficiencies that Petitioners
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`cannot fix with a trial. The ’459 patent addresses an important technological issue:
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`preventing an authorized user from copying secure information to an unsecured
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`removable device. The claims of the ’459 patent reflect this innovation, requiring
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`that the computer prevents writing to devices when security information is not
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`sensed. Petitioners’ cited references do not address this issue and significantly
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`differ from the challenged claims.
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`This Preliminary Response lays out the facts that show Petitioners have not
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`met their burden. In Section II, Patent Owner provides a roadmap of the ’459
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`patent, showing how the patent solved the problem of preventing authorized users
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`from copying sensitive data to unsecured removable storage devices. Section III
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`sets forth Patent Owner’s position why no explicit claim construction is necessary
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`to resolve this dispute, and Sections IV–V each address Petitioners’ failure to meet
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`their burden for the two asserted grounds. For example, Ground 1 fails because
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`Petitioners do not show that the combination of Blakley and Bramhill discloses the
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`“sensing” elements recited in independent claims 15 and 18. Ground 2 fails
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`because Petitioners do not show that the combination of Uchida and Bramhill
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`IPR2017-00467
`Patent No. 6,968,459
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`discloses the “providing restricted-access” and “sensing” elements of independent
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`claims 15 and 18.
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`This Preliminary Response will show that Petitioners have not met their
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`burden to establish a reasonable likelihood of prevailing against any challenged
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`claim. The Board should therefore deny all of Petitioners’ proposed grounds.
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`II. The ’459 patent solved the important problem of preventing authorized
`users from copying sensitive data to unsecured removable storage
`devices.
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`In 1999, engineers at Imation Corporation recognized that “[o]ne of the
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`greatest challenges” in creating a secure computing environment is “preventing the
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`authorized user from using sensitive data in an unauthorized manner.” (Ex. 1001,
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`’459 patent, 1:13–23.) For example, prior to the ’459 patent, after a user
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`successfully entered a password, the user was able to access and handle
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`information without technology-imposed limitations. The lack of access control
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`meant that an authorized user could “simply copy[] the sensitive data to a
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`removable storage device such as floppy diskette.” (’459 patent, 1:23–26.)
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`To address this critical security flaw, the inventors of the ’459 patent
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`developed a computing environment using secure storage devices where, for
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`example, “a computer automatically operates in a secure ‘full-access’ data storage
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`mode when the computer detects the presence of a secure removable storage
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`device.” (’459 patent, 1:36–40.) Conversely, “[i]f the computer senses a non-
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`secure removable storage device then the computer automatically operates in a
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`‘restricted-access’ mode.” (’459 patent, 1:40–43.) Figure 1, reproduced below,
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`illustrates an embodiment of such a computing environment.
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`In secure full-access mode, the system “uses a cryptographic key to encrypt
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`and decrypt the data stream between the computer and the removable storage
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`device.” (’459 patent, 1:44–47.) The key can be generated by a combination of
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`various types of information such as “(1) device-specific information derived of
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`the removable storage device, (2) manufacturing information that has been etched
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`onto the storage device, (3) drive-specific information…, and (4) user-specific
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`information such as a password.” (’459 patent, 1:47–55.) Figure 2, reproduced
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`below, illustrates an exemplary method requiring the four types of information
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`identified in the figure (204, 206, 208, 210) are required for a storage device to be
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`deemed secure and have “full access.”
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`The patent contemplates two situations: where the storage device is secure
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`and where the storage device is unsecured. When the storage device is secure, the
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`computing environment uses the “secure storage device as a secure ‘access card’”
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`to gain access to sensitive data of the organization. (’459 patent, 1:56–58.) For
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`Patent No. 6,968,459
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`example, the computer allows the user to access sensitive information from other
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`sources after plugging in a secure storage device. (See ’459 patent, 1:58–62.)
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`Sensitive information written to the secure storage device can be encrypted. (See
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`’459 patent, 1:44–47.) Conversely, if the storage device is unsecured, the computer
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`operates such that the user cannot write to the device, preventing the removal of
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`sensitive information from the computer when using an unsecured device. (See
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`’459 patent, 1:63–66.)
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`III. Claim construction.
`Petitioners propose constructions for four terms— “device-specific security
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`information,” “[device/user]-specific information,” “security information,” and
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`“detecting a storage device within a storage drive.” (See Petition, pp. 9–16.)
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`The Board should not adopt constructions for any of these terms for two
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`reasons. First, construction is not “necessary to resolve the controversy” in this
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`proceeding. Vivid Techs. v. Amer. Science, 200 F.3d 795, 803 (Fed. Cir. 2000).
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`Second, the meaning of each claim term is clear and therefore no further
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`construction is required. Phillips v. AWH Corp., 415 F.3d 1303, 1312 (Fed. Cir.
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`2005).
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`IV. The Board should exercise its discretion under 35 U.S.C. § 325(d) to
`deny the Petition because it presents a substantially similar argument
`that the Board denied in a previous IPR petition against the ’388 patent.
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`Congress gave the Board discretion to “reject the petition or request because,
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`the same or substantially the same prior art or arguments previously were
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`presented to the Office.” 35 U.S.C. § 325(d). “[S]ubstantial similarity of argument,
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`standing alone, is sufficient for a denial under § 325(d).” Conopco dba Unilever v.
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`Proctor and Gamble Co., IPR2014-00628, Decision Denying Institution at p. 10
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`(Paper 21, Oct. 20, 2014).
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`The Board should exercise this discretion to deny institution of the present
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`proceeding. The Board has already considered and rejected a challenge to the
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`claims based on an argument that comparison of two values constitutes “sensing
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`whether the storage device has security information.” Here, Petitioners repackage
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`that argument already rejected by the Board, relying on substantially similar
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`disclosures of its asserted art for the same claim elements.
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`In January 2017, the Board denied grounds against claims 15 and 18 of the
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`’388 patent. Unified Patents Inc. v. Intellectual Ventures II, LLC, IPR2016-01404,
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`Institution Decision at pp. 17–20 (Paper 9, Jan. 11, 2017). In its decision, the
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`Board rejected the petitioner’s assertion that comparison of a security code with
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`another security code constitutes “sensing whether the storage device has security
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`information generated from a combination of device-specific information
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`associated with the storage device and user-specific information associated with a
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`user” as recited in claim 18. Id. at 18. Specifically, the Board such a comparison
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`“does not address sensing whether [the storage device] contains [the alleged
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`security information].” Id. at 19. The Board therefore found that the petitioner did
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`not meet its burden of establishing that obviousness of claim 18 of the ’388 patent.
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`Here, Petitioners make the same argument based on Blakley’s bit strings and
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`Uchida’s passwords in lieu of the security code of the first petition. In both
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`Grounds, Petitioners argue that the alleged security information is stored on the
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`storage device, and that comparing the stored information to an entered value
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`satisfies the “sensing” elements of independent claims 15 and 18. For Ground 1, in
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`the only sentence addressing the art’s disclosure of the claim 15 “sensing” element,
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`Petitioners argue that “Blakely teaches that a… bit string is generated and stored
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`on the storage device during installation, and later checked against a
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`pseudorandom bit string generated when a user logs on.” (Petition, p. 28
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`(emphasis added).) Petitioners rely on the same disclosure for claim 18. (Petition,
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`p. 37.) Like the argument the Board rejected in the first petition, Petitioners only
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`cite to a comparison for alleged disclosure of the “sensing” elements, and the
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`Board should exercise its discretion to deny Ground 1 for that reason.
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`For Ground 2, Petitioners cite to Uchida’s alleged disclosure of “permitting
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`full access to a storage medium if a password for the medium is consistent with the
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`stored password(s)” for the “sensing” elements. (Petition, p. 52 (citing Uchida,
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`3:20–30).) Petitioners further argue that the “passwords are stored… and must
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`coincide with a separate user entered password” (Petition, p. 54) and that “access is
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`restricted depending on whether the user-inputted password coincides with one of
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`the predetermined passwords.” (Petition, p. 62.) Thus, Petitioners argument is
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`substantially similar to the argument the Board denied in the first petition in that it
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`equates a comparison of a stored password to a user-entered password with the
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`“sensing” elements recited in claims 15 and 18.
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`The Board has already considered and rejected substantially similar
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`arguments as those Petitioners present in the instant Petition. Accordingly, the
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`Board should exercise its discretion to deny institution under § 325(d).
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`V. Ground 1: The Board should deny institution because Petitioners have
`not established a reasonable likelihood that the combination of Blakley
`and Bramhill renders claims 15, 18, 24, and 25 obvious.
`A. Overview of Blakley.
`Blakley discloses a method “to protect the confidentiality of information
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`stored on a storage device of a computer, even if the computer is stolen or
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`otherwise accessed without the owner’s consent or knowledge.” (Blakley, 1:44–
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`47.) Blakley accomplishes this goal using software that operates in two stages: an
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`installation stage (see Blakley, 5:41 to 6:12) and an access stage (see Blakley,
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`6:13–47.) The figure below illustrates the installation process described in Blakley,
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`Patent No. 6,968,459
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`with annotations to corresponding disclosures of Blakley. (See Blakley, 5:41 to
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`6:12.)
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`Figure A – Block Diagram of Blakley
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`During the first step of the installation process, a user enters a password.
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`Blakley uses this user-entered password for two separate functions: 1) user
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`verification during subsequent logon attempts, and 2) generation of the
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`pseudorandom bit string for data encryption. (See Blakley, 5:42–44.) In both
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`functions, the password is masked to create a secret key: “Information dependent
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`on the user password is then combined with (non-secret) information (e.g., a
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`mask…) to determine a secret key, 𝑎, for the user.” (Blakley, 5:44–48.) For the
`user verification function, the secret key 𝑎 is processed through a one-way function
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`to produce a result that can be stored “on the mass storage device to allow the key
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`processing unit to distinguish correct and incorrect passwords.” (Blakley, 5:66 to
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`6:2.) Because a one-way function is applied, the secret key cannot be derived from
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`the stored value. Blakley stores the result of the one-way function in storage. (See
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`Blakley, 5:66 to 6:2.) Importantly, security is maintained because neither the
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`password nor the secret key is stored on the disk. (See Blakley, 2:25–32 and 6:2–
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`3.)
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`Blakley’s installation process also performs encryption of data stored on the
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`drive. During the installation process, data is read from each sector of interest,
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`encrypted, and written back to the same sector. (See Blakley, 6:4–11.) The cipher
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`used by Blakley for encryption (also referred to as a pseudorandom bit string) is a
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`function of a secret key and an index specifying the data’s position on the storage
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`device. Because of the computational overhead associated with any cryptographic
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`operation, Blakley performs pre-processing on the secret key. Specifically, for the
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`Blakley, 5:61–63; see also 2:33–35 and 8:8–10.) Pre-processing the secret key in
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`this manner, before it is used in an encryption operation, allows the pseudorandom
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`data encryption function, the secret key is pre-processed to form a cipher 𝑓𝑎. (See
`bit string cipher to be efficiently computed in real-time for each sector index 𝑖
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`every time a sector is accessed. (Blakley, 2:35–42, 6:29–32.) The computed cipher
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`is used to encrypt the information stored on the disk in plaintext that “the user
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`wishes to have [ ] kept private.” (Blakley, 6:4–6.) Specifically, “[w]hen the string 𝑥
`at position 𝑖 of the disk is read, the value 𝑓𝑎(𝑖) is computed by the computing
`system.” (Blakley, 6:6–8.) The data is encrypted when “[a] value 𝑦 is computed by
`XORing or otherwise combining 𝑥 and 𝑓𝑎(𝑖),” and the encrypted data “𝑦 replaces
`the previous value 𝑥 for the contents of the sector.” (Blakley, 6:8–12.)
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`After installation, during the access process, a user logs onto the machine by
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`inputting the password. (See Blakley, 6:13–16.) Similar to installation, the
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`password is verified by creating a secret key, passing the secret key through a one-
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`way function, and checking the result “against information stored in the computing
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`process. (See Blakley, 6:16–21.) At this point, whenever the user wants to read
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`device” (i.e., the one-way function of 𝑎 stored during installation). (Blakley, 6:21–
`25.) The system also creates the cipher 𝑓𝑎 in a similar manner as the installation
`encrypted information from the 𝑖-th sector of the disk, “the software computes
`𝑓𝑎(𝑖)” and “retrieves the contents of the 𝑖-th sector of the disk.” (Blakley, 6:29–
`33.) The retrieved encrypted value “is XORed with 𝑓𝑎(𝑖) to determine the
`‘plaintext’ 𝑥.” (Blakley, 6:34–36.) When the user wants to write information to the
`𝑖-th sector, Blakley again calculates 𝑓𝑎(𝑖) and XORs the unencrypted information
`with 𝑓𝑎(𝑖) to form the encrypted version 𝑦. The resulting encrypted data is then
`stored on the 𝑖-th sector of the disk. (See Blakley, 6:39–47.)
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`B. Overview of Bramhill.
`Bramhill appears to be a technical article titled “Challenges for Copyright in
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`a Digital Age.” As the title suggests, the article is concerned with copyright
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`protection, “propos[ing] an initial model of a software-based system that provides
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`copyright protection of multimedia information when delivered by Internet-based
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`services.” (Bramhill, p. 63, Abstract.)
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`Bramhill argues for a “strong one-to-one binding between the software of a
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`user, and the user.” (Bramhill, p. 67, § 3.1 ¶ 2.) For the purposes of this
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`proceeding, Petitioners focus primarily on the binding described in Section 3.2,
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`which is titled “Binding software to a machine.” (Bramhill, p. 67, § 3.2.) This
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`section discusses “a number of characteristics of a computer [that] can be
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`measured to achieve a similar level of probability of its identity,” termed
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`“cybermetrics” by Bramhill. (Bramhill, p. 67, § 3.2 ¶ 1.) Bramhill lists nine
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`examples of cybermetrics including size of memory, the presence of a CD drive,
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`“operational characteristics,” manufacturer of physical components, logical
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`directory and file structures, or files specifically created to identify the machine.
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`(See Bramhill, p. 67, § 3.2.)
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`Bramhill discloses that a fraudster “would have to recreate both the logical
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`and physical characteristics of” a machine belonging to another user in order “to
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`make use of a software decryption processing belonging to” that user. (Bramhill,
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`p. 67.) However, Bramhill provides no details as to how its “cybermetrics”—a
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`term Bramhill only uses once—could be used to thwart copyright infringement.
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`C.
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`Petitioners have not established a reasonable likelihood that the
`combination of Blakley and Bramhill renders independent claim
`15 obvious.
`1.
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`Petitioners have not established a reasonable likelihood of
`showing that the combination discloses the “sensing”
`element of claim 15.
`Claim 15 recites “sensing whether a storage device has device-specific
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`security information stored thereon.” Petitioners address this claim element by
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`parsing it into two parts, “device-specific security information” and “sensing.”
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`Petitioners’ piecemeal approach is fatal to its arguments. As Patent Owner
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`demonstrates below, Petitioners fail to establish that the combination of Blakley
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`and Bramhill teach or suggest this claim element.
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`Petitioners present three different arguments regarding whether the
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`combination teaches or suggests “device-specific security information” in isolation.
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`(See Petition, pp. 26–29.) First, Petitioners argue Blakley’s “pseudorandom bit
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`string” that is used to encrypt data stored on a storage device is “device-specific
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`security information.” (See Petition, pp. 26–27.) Second, Petitioners argue that
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`Blakley’s value identification could be considered “device-specific security
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`information” should the Board adopt a broad claim construction for the term. (See
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`Petition, pp. 27–28.) Third, Petitioners turn to Bramhill, arguing that Bramhill’s
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`“cybermetrics” when combined with Blakley teach or suggest “device-specific
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`security information.” (See Petition, pp. 28–29.)
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`But when Petitioners address the “sensing” part of the claim element,
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`Petitioners only rely on Blakley’s “pseudorandom bit string.” (See Petition, p. 28.)
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`Accordingly, Petitioners’ second and third arguments have not established that the
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`combination of Blakley and Bramhill teach or suggest this claim element.
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`However, for completeness, Patent Owner demonstrates that none of Petitioners’
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`three arguments has a reasonable likelihood of success. The Board should therefore
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`deny institution of Ground 1 for claim 15.
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`a) Petitioners fail to show that Blakley discloses “sensing
`whether a storage device has” the pseudorandom bit string
`“stored thereon.”
`Petitioners’ first argument fails because Petitioners do not and cannot show
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`that Blakley teaches or suggests “sensing whether a storage device has” the
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`pseudorandom bit string “stored thereon.” Petitioners’ argument ignores a key
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`portion of the claim element—that the sensing action determines whether the
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`device-specific security information is stored on the storage device. Petitioners’
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`omission is not surprising because Blakley never stores the pseudorandom bit
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`string on the storage device. Petitioners attempt to obscure this fatal flaw in
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`Blakley by mischaracterizing the teachings of Blakley. But when Petitioners’
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`subterfuge is stripped away, the explicit disclosures of Blakley, as well as the
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`nature of the pseudorandom bit string itself, make clear that Petitioners’ argument
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`fails.
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`In Blakley, “the function that produces the pseudorandom bit string for each
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`sector index, and any other information (e.g., the secret key) useful in encrypting
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`and decrypting disk accesses, is preferably stored in volatile memory when the
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`machine is in use” and is “erased” when “the authorized user logs off, powers off,
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`locks the computer, or when a predetermined timeout occurs.” (Blakley, 6:48–57
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`(emphasis added).) The pseudorandom bit strings are undoubtedly “other
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`information… useful in encrypting and decrypting disk accesses” (Blakley, 6:48–
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`53) because they are “used to encrypt and decrypt data accesses” (Blakley,
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`Abstract). The pseudorandom bit strings are erased and therefore not stored to the
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`storage device.
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`Blakley also discloses that the pseudorandom bit strings are generated each
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`time the system accesses a protected portion of the disk. Describing the installation
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`process, Blakley states that “[w]hen the string 𝑥 at position 𝑖 of the disk is read, the
`value 𝑓𝑎(𝑖) is computed by the computing system.” (Blakley, 6:6–8.) Afterward,
`when “the operating system will attempt to read the 𝑖-th sector from the disk… the
`software computes 𝑓𝑎(𝑖)” again, in order to decrypt the information on the disk.
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`(Blakley, 6:26–32; see 6:32–36.) If it were stored on the disk, the system could
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`simply access that stored value instead of re-computing it. Blakley’s disclosure can
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`lead to only one conclusion—that the pseudorandom bit strings are erased (not
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`stored) and must be regenerated.
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`Furthermore, a person of ordinary skill in the art (“POSITA”) would
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`recognize that Blakley’s pseudorandom bit string is not stored on the storage
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`device for several reasons. First, storing the key used to encrypt/decrypt data with
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`the data would undermine the entire purpose of Blakley, rendering it inoperable for
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`its intended purpose. In re Gordon, 733 F.2d 900, 902 (Fed. Cir. 1984). If Blakley
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`stored the cipher (key) used to encrypt and decrypt the stored data with the
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`encrypted data, an unauthorized user could access the cipher and decrypt the data,
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`defeating Blakley’s purpose of “protect[ing] the confidentiality of information
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`stored on a storage device of a computer.” (Blakley, 1:44–47.) Second, storing the
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`pseudorandom bit strings would take an enormous amount of storage space
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`because each bit string is the same length as the data that it encrypts. (See Blakley,
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`3:49–56 (“[A] pseudorandom bit string [] will have a length equal to the area of the
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`storage device in which the data will be stored. If the storage device is a hard disk
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`drive, the area is a ‘sector.’”).) Thus, under Petitioners’ theory, half of the storage
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`device would have to be devoted to storing pseudorandom bit strings
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`corresponding to each sector of encrypted information. In addition to being
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`counterintuitive, the argument contradicts Blakley, which discusses “encrypting
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`the entire disk,” and makes no mention of being limited to only encrypting half of
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`it. (Blakley, 7:6–10.)
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`Petitioners fail to discuss any of these issues, addressing the storage
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`requirement in a carefully-worded, three-sentence paragraph that mischaracterizes
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`Blakley. Petitioners state that “Blakley teaches that a device-specific…
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`pseudorandom bit string is generated and stored on the storage device during
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`installation, and later checked against a pseudorandom bit string generated when a
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`user logs on or otherwise initiates a request to access secure information.”
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`(Petition, p. 28.) But this is not what Blakley discloses. The value that Petitioners
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`describe as being “stored on the storage device during installation” (Petition, p. 28)
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`is not the “pseudorandom bit string” in Blakley. Rather, Blakley refers to this value
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`as a “one-way function of the secret key.” (Blakley, 5:66 to 6:2.) And the
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`distinction between the two values is critical. The figure below highlights the
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`differences between these two values.
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`Figure B – Annotated Block Diagram of Blakley
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`Blakley’s pseudorandom bit string used as its cryptographic cipher is not
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`“stored on the storage device during installation” and is not “later checked” against
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`a value generated when a user logs on. (Petition, p. 28.) The portion of Blakley
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`cited by Petitioners explicitly states that the result of the “one-way function of the
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`secret key” is stored and later checked during password verification. (See Blakley,
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`5:66–6:2 and 6:21–25 (“A one-way function of the secret key 𝑎 is installed on the
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`mass storage device to allow the key processing unit to distinguish correct and
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`incorrect passwords.”).) As its name implies, the result of the one-way function of
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`the secret key is generated from the secret key. Petitioners do not argue that the
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`result of the one-way function is the “device-specific security information.” Nor
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`can they. Petitioners contend that the dependence on the sector index 𝑖 is what
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`made the pseudorandom bit string used as the cryptographic cipher “device-
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`specific.” (See Petition, pp. 26–27.) The result of the one-way function of the secret
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`key does not utilize or depend in any way on the sector index.
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`The Board should reject Petitioners’ sleight of hand. Petitioners’ identified
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`Blakley’s pseudorandom bit string used as its cryptographic cipher as the recited
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`“device-specific security information” of claim 15. Therefore, to meet their burden
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`of showing that Blakley teaches or suggest the entire claim element, Petitioners
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`must point to some disclosure of sensing whether the pseudorandom bit string used
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`as a cryptographic cipher is stored on the storage device. The Petitioners did not
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`and cannot because Blakley does not store its cryptographic cipher to maintain
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`security of its data. The fact that Blakley stores an entirely different value derived
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`from the secret key in storage is not sufficient or even relevant, regardless of
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`Petitioners’ attempt to improperly place the same label on the values. KSR Int’l Co.
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`v. Teleflex Inc., 550 U.S. 398, 418 (2007).
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`b) Petitioners fail to establish that a POSITA would have
`combined Blakley and Bramhill to meet the “sensing”
`element of claim 15.
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`Petitioners argue that “Bramhill also teaches using ‘device-specific security
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`information’” and that “a POSA would have understood that the disclosures of
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`Blakley in view of Bramhill disclose, teach, or suggest this limitation.” Petitioners’
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`argument fails for two reasons. First, Petitioners provide no articulated reasoning
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`nor rational underpinnings supporting the combination, and never even explain
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`what the combination is. See KSR, 550 U.S. at 418 (“there must be some
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`articulated reasoning with some rational underpinning to support the legal
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`conclusion of obviousness”); Los