Microsoft Corporationv.Proxyconn, Inc.

Patent Trial and Appeal Board

Feb 19, 2014

09398007 (P.T.A.B. Feb. 19, 2014)

Trials@uspto.gov Paper 73
Tel: 571-272-7822 Entered: February 19, 2014
UNITED STATES PATENT AND TRADEMARK OFFICE

BEFORE THE PATENT TRIAL AND APPEAL BOARD

MICROSOFT CORPORATION
Petitioner
v.
PROXYCONN, INC.
Patent Owner

Case IPR2012-00026
Case IPR2013-00109
Patent 6,757,717

Before SALLY C. MEDLEY, THOMAS L. GIANNETTI, and
MITCHELL G. WEATHERLY Administrative Patent Judges.
WEATHERLY, Administrative Patent Judge.
FINAL WRITTEN DECISION
35 U.S.C. § 318(a) and 37 C.F.R. § 42.73
Cases IPR2012-00026 and IPR2013-00109
Patent 6,757,717
2
I. BACKGROUND
A. Introduction
On September 18, 2012, Microsoft Corporation (“Microsoft”), filed a
petition under 35 U.S.C. §§ 311-319 for inter partes review of claims 1, 3,
10–12, 14, and 22–24 of U.S. Patent No. 6,757,717 (“the ’717 Patent”).
IPR2012-00026, Paper 6 (“the ’026 Petition”). We granted the ’026 Petition
as to certain challenges to the patentability of claims 1, 3, 10, and 22–24,
and denied the ’026 Petition as to all challenges to the patentability of claims
11, 12, and 14 on December 21, 2012. IPR2012-00026, Paper 17 (“the ’026
Decision”).
Soon afterward, on January 11, 2013, Microsoft filed a second
petition for inter partes review, this time challenging the patentability of
claims 6, 7, 9, 11, 12, and 14 of the ’717 Patent. IPR2013-00109, Paper 1
(“the ’109 Petition”). Microsoft concurrently filed a motion to join
IPR2013-00109 with IPR2012-00026. IPR2013-00109, Paper 7. We
granted the ’109 Petition as to certain challenges to patentability of claims 6,
7, 9, 11, 12, and 14 of the ’717 Patent. IPR2013-00109, Paper 14 (“the ’109
Decision”). We also granted Microsoft’s motion for joinder and joined
IPR2013-00109 with IPR2012-00026. IPR2013-00109, Paper 15.
After institution and joinder of both trials, Proxyconn, Inc.
(“Proxyconn”) filed its Corrected Patent Owner’s Response (“Resp.”).
Paper 45.1 Proxyconn also filed Patent Owner’s Corrected Motion to
Amend (“Mot. Amend”) in which Proxyconn moved to substitute claims 35–

1 This reference to “Paper” and all other references to “Paper” from this
point forward in this Final Written Decision are to papers filed in the joined
proceeding, which is captioned as IPR2012-00026 and IPR2013-00109.
Cases IPR2012-00026 and IPR2013-00109
Patent 6,757,717
3
41 for claims 1, 3, 6, 10, 11, 22, and 23, respectively, if the Board were to
cancel any of those challenged claims as unpatentable. Paper 44.2 This
Final Written Decision addresses challenges to the patentability of claims 1,
3, 6, 7, 9–12, 14, and 22–24. Because claims 1, 3, 6, 10, 11, 22, and 23 are
found unpatentable, this Decision also addresses the patentability of
proposed substitute claims 35–41.
B. The ’717 Patent
The ʼ717 Patent describes a system for data access in a packet
switched network. Ex. 1002, Abstract. The system has a sender/computer
including an operating unit, a first memory, a permanent storage memory,
and a processor. The system also has a remote receiver/computer including
an operating unit, a first memory, a permanent storage memory, and a
processor. The sender/computer and receiver/computer communicate
through the network. Id. The sender/computer further includes a device for
calculating digital digests on data; the receiver/computer further includes a
network cache memory and a device for calculating digital digests on data in
the network cache memory; and the receiver/computer and/or the
sender/computer includes a device for comparison between digital digests.
Id.
As described in the ’026 Petition, the ʼ717 Patent provides a way to
reduce the amount of redundant data transmitted over a network. ’026
Petition, 4. The processes described in the ’717 Patent check for the identity

2 Proxyconn filed Patent Owner’s Motion to Amend under 37 C.F.R.
§ 42.121 on May 21, 2013. Paper 37. In an Order entered June 20, 2013,
Proxyconn was granted permission to file its Corrected Motion to Amend to
address typographical errors and file corrected exhibits. Paper 43.
Proxyconn filed its Corrected Motion to Amend later that same day.
Cases IPR2012-00026 and IPR2013-00109
Patent 6,757,717
4
between two sets of data by comparing respective digital fingerprints of that
data. Id. As described in the Summary of the Invention:
If a sender/computer in the network is required to send
data to another receiver/computer, and the receiver/computer
has data with the same digital digest as that of the data to be
sent, it can be assumed with sufficient probability for most
practical applications that the receiver/computer has data which
is exactly the same as the data being sent. Then, the
receiver/computer can use the data immediately without its
actual transfer through the network. In the present invention,
this idea is used in a variety of ways.
Ex. 1002, col. 2, ll. 16-24.
The patent discloses several embodiments. In one, a sender/computer
required to send data to a receiver/computer initially sends a digital digest of
the data. If the receiver/computer already has data with the same digital
digest, it uses this data as if it were actually transmitted from the
sender/computer. Id. at col. 2, ll. 26-31. This embodiment is illustrated in
Figures 5-7. Figure 5 is reproduced below:
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Cases IPR2012-00026 and IPR2013-00109
Patent 6,757,717
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In this embodiment the sender/computer sends the principal and
auxiliary (e.g., of a previous version of the data requested) digests to the
receiver/computer. Upon receiving a message with these digital digests
from the sender/computer, the receiver/computer searches its network cache
memory for data having the same principal digest. If such data is found, the
receiver/computer uses the data as if the data were received from the
sender/computer and issues a positive indication signal to the
sender/computer. Otherwise, the receiver/computer searches its network
cache memory for data with the auxiliary digests. If it finds data with a
digital digest substantially equal to one of the auxiliary digests, it issues a
partial indication signal to the sender/computer, along with a reference to the
digest. Otherwise it issues a negative indication signal to the
sender/computer. Id. at col. 8, ll. 11-39.
C. Exemplary Claims
Claims 1, 6, 10, 11, and 22 are the independent claims among the
challenged claims of the ’717 Patent. Claims 1, 6, and 10 are directed to
systems, and claims 11 and 22 are directed to methods. The independent
challenged claims, which are illustrative of the claims at issue in this inter
partes review, recite:
1. A system for data access in a packet-switched
network, comprising:
a sender/computer including an operating unit, a first
memory, a permanent storage memory and a processor and a
remote receiver/computer including an operating unit, a first
memory, a permanent storage memory and a processor, said
sender/computer and said receiver/computer communicating
through said network;
Cases IPR2012-00026 and IPR2013-00109
Patent 6,757,717
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said sender/computer further including means for
creating digital digests on data;
said receiver/computer further including a network cache
memory and means for creating digital digests on data in said
network cache memory; and
said receiver/computer including means for comparison
between digital digests.
6. A system for data access in a packet-switched
network, comprising:
a gateway including an operating unit, a memory and a
processor connected to said packet-switched network in such a
way that network packets sent between at least two other
computers pass through it;
a caching computer connected to said gateway through a
fast local network, wherein said caching computer includes an
operating unit, a first memory, a permanent storage memory
and a processor;
said caching computer further including a network cache
memory in its permanent storage memory, means for
calculating a digital digest and means for comparison between a
digital digest on data in its network cache memory and a digital
digest received from said packet-switched network through said
gateway.
10. A system for data access in a packet-switched
network, comprising:
a sender/computer including an operating unit, a first
memory, a permanent storage memory and a processor and a
remote receiver/computer including an operating unit, a first
memory, a permanent storage memory and a processor, said
sender/computer and said receiver/computer communicating
through a network;
said sender/computer further including means for
creating digital digests on data, and
Cases IPR2012-00026 and IPR2013-00109
Patent 6,757,717
9
said receiver/computer further including a network cache
memory, means for storing a digital digest received from said
network in its permanent storage memory and means for
comparison between digital digests.
11. A method performed by a sender/computer in a
packet-switched network for increasing data access, said
sender/computer including an operating unit, a first memory, a
permanent storage memory and a processor and said
sender/computer being operative to transmit data to a
receiver/computer, the method comprising the steps of:
creating and transmitting a digital digest of said data
from said sender/computer to said receiver/computer;
receiving a response signal from said receiver/computer
at said sender/computer, said response signal containing a
positive, partial or negative indication signal for said digital
digest, and
if a negative indication signal is received, transmitting
said data from said sender/computer to said receiver/computer.
22. A method for increased data access performed by a
receiver/computer in a packet-switched network, said
receiver/computer including an operating unit, a first memory, a
permanent storage memory, a processor and a network cache
memory, said method comprising the steps of:
receiving a message containing a digital digest from said
network;
searching for data with the same digital digest in said
network cache memory,
if data having the same digital digest as the digital digest
received is not uncovered, forming a negative indication signal
and transmitting it back through said network; and
creating a digital digest for data received from said
network cache memory.
Cases IPR2012-00026 and IPR2013-00109
Patent 6,757,717
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Ex. 1002, col. 10, l. 31 to col. 12, l. 45.
D. Remaining Challenges to the Patentability of Claims
We instituted this inter partes review in connection with the following
challenges to the patentability of claims in the ’717 Patent:3
1. Anticipation by Perlman: claims 1, 3, and 22-24;
2. Anticipation by Yohe: claims 1, 3, 6, 7, 10, 22, and 23;
3. Anticipation by Santos: claims 1, 3, 10, 22, and 23;
4. Anticipation by DRP: claims 6, 7, 9, 11, 12, and 14;
5. Obviousness over the combination of Perlman and Yohe: claims 1, 3,
10, and 22-24; and
6. Obviousness over the combination of Mattis and DRP: claims 6, 7, 9,
11, 12, and 14.
’026 Decision 25–26; ’109 Decision 20.
II. ANALYSIS
A. Claim Interpretation
We interpret patent claim language in an inter partes review by
ascribing to that language its broadest reasonable meaning in light of the
specification of the patent. 37 C.F.R. § 42.100(b); Office Patent Trial

3 The challenges to patentability are based upon five prior art references: US
5,742,820, issued Apr. 21, 1998 (Ex. 1003) (“Perlman”); US 5,835,943,
issued Nov. 10, 1998 (Ex. 1005) (“Yohe”); Santos and Wetherall,
INCREASING EFFECTIVE LINK BANDWIDTH BY SUPPRESSING REPLICATED
DATA (June 1998) (Ex. 1004 ) (“Santos”); THE HTTP DISTRIBUTION AND
REPLICATION PROTOCOL, W3C Note (August 25, 1997), retrieved from
http://www.www3.org/TR/NOTE-drp-19970825 (IPR2013-00109,
Ex. 1003) (“DRP”); US 6,292,880 B1, issued Sep. 18, 2001 (IPR2013-
00109, Ex. 1004) (“Mattis”).
Cases IPR2012-00026 and IPR2013-00109
Patent 6,757,717
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Practice Guide, 77 Fed. Reg. 48,756, 48,766 (Aug. 14, 2012). We also
interpret claim language according to its ordinary and customary meaning to
one of ordinary skill in the art in the context of the entire disclosure. In re
Translogic Tech., Inc., 504 F.3d 1249, 1257 (Fed. Cir. 2007).
We expressly interpret below only those claim terms that require
analysis to resolve arguments related to the patentability of the challenged
claims. Except as otherwise stated, we interpret the remaining claim terms
as set forth in the ’026 Decision and the ’109 Decision.
1. Data Access
Each contested claim recites “data access.” Ex. 1002, col. 10, l. 31
(claims 1, 3), col. 10, l. 64 (claims 6, 7, and 9), col. 11, l. 20 (claim 10),
col. 11, l. 35 (claims 11, 12, and 14), col. 12, l. 30 (claims 22–24).
Proxyconn urges that “data access” means “obtaining data . . . on a remote
computer on a network, in response to a request from a client.” Resp. 11
(citing Ex. 1002, col. 1, ll. 18–26; id. at col. 7, ll. 65–67). In support,
Proxyconn cites portions of the Specification of the ’717 Patent that describe
exemplary data transmission sessions in which a network client “requests”
data from a server. The first cited portion describes such interactions
between a client and server as “prior art.” Ex. 1002, col. 1, ll. 18–26. The
second cited portion states: “This transaction begins with a
receiver/computer sending a request to the sender/computer.” Id. at col. 7,
ll. 65–67. The phrase “[t]his transaction” refers to the interaction between
the receiver/computer and the sender computer depicted in Figures 5–7 of
the ’717 Patent. Id. at col. 7, ll. 51–67.
By contrast, Microsoft contends that “data access” means “data
acquisition.” Microsoft Corporation’s Reply to Patent Owner’s Corrected
Cases IPR2012-00026 and IPR2013-00109
Patent 6,757,717
12
Response (“MS Reply”), 2 (Paper 46). Microsoft dismisses the portions of
the Specification that Proxyconn cites as neither mentioning “data access”
nor narrowly defining “data access.” Id. Microsoft argues that other
portions of the Specification imply that the step of the receiver/computer
requesting data is merely optional. Id. (citing Ex. 1002, 8:37–39).
Proxyconn’s expert, Dr. Konchitsky, testified that the Specification
describes scenarios in which a sender transmits data to a receiver without a
request from the receiver. See Ex. 1024, 69:1–24, 71:8–22 (describing the
data communication method illustrated in Figure 8 of the ’717 Patent).
Microsoft also points out that claim 32, which is not challenged, explicitly
recites a method in which a client sends a request for data to a server. Paper
72, Final Hearing Transcript 10:9-12, 79:22–80:9 (“Tr.”).
Both parties’ interpretations of “data access” are too narrow. Neither
the challenged claims nor the Specification expressly limits “data access” to
require a “request from the client” as proposed by Proxyconn. The claims
merely recite “data access.” Even though the Specification describes
examples in which the client requests data from a server, the Specification
does not require that the client request data in all described embodiments of
the claimed systems and methods. For example, the Specification expressly
describes an embodiment in which “a sender/computer required to send data
to a receiver/computer . . . initially sends a digital digest of the data.”
Ex. 1002, col. 2, ll. 26–28. “[L]imitations are not to be read into the claims
from the specification.” In re Van Geuns, 988 F.2d 1181, 1184 (Fed. Cir.
1993) (citing In re Zletz, 893 F.2d 319, 321(Fed. Cir. 1989)). We decline to
do so here.
Cases IPR2012-00026 and IPR2013-00109
Patent 6,757,717
13
Microsoft’s position is similarly unsupported by the claims
themselves or the Specification. None of the challenged independent claims
affirmatively recites that the receiver/computer acquires data from the
sender/computer. Microsoft cites no portion of the Specification, and we
find no support for the proposition that the Specification equates “data
access” with “data acquisition.”
We determine that the plain meaning of “data access” is clear.
Independent challenged claims 1, 6, 10, 11, and 22 recite “access” as a noun
modified by “data.” Ex. 1002, col. 10, l. 31 (claims 1, 3), col. 10, l. 64
(claims 6, 7, and 9), col. 11, l. 20 (claim 10), col. 11, l. 35 (claims 11, 12,
and 14), col. 12, l. 30 (claims 22–24). “Access” plainly means the “freedom
or ability to obtain or make use of.” MERRIAM WEBSTER’S COLLEGIATE
DICTIONARY 6 (10th ed. 1999). We conclude, therefore, that the claimed
systems and methods recite “data access” to refer to the freedom or ability to
obtain or use data. Although obtaining or acquiring data requires access to
that data, access to the data need not involve acquisition of that data.
2. Permanent Storage Memory
Claims 1, 3, 6, 7, 9, 10, and 22–24 recite “permanent storage
memory.” Ex. 1002, col. 10, l. 31 – col. 13, l. 8. Proxyconn argues that
“permanent storage memory” means non-volatile memory that can be used
for writing and reading data and does not refer to read-only memory
(“ROM”). Resp. 12. The Specification states “an example of a permanent
storage memory may be a disk drive, a flash RAM or a bubble memory.”
Ex. 1002, col. 7, ll. 38–40. In support of its proffered definition of
“permanent storage memory,” Proxyconn also cites Yohe’s statement that
“‘[p]ermanent storage memory,’ as used herein, includes but is not limited
Cases IPR2012-00026 and IPR2013-00109
Patent 6,757,717
14
to, disk drive, flash RAM or bubble memory, for example.” Resp. 12
(quoting Ex. 1005, col. 3, ll. 5–7).
Microsoft counters that “permanent storage memory” is not restricted
to non-volatile memory that permits multiple write operations, but may also
include storage that is write-once, read-many (“WORM”) memory. MS
Reply 2. Microsoft contends that a CD optical storage disc, a type of non-
volatile WORM memory, would constitute permanent storage memory. See
id. (citing Ex. 1024, 88:7–89:12). Thus, the dispute centers on whether
“permanent storage memory” encompasses ROM and other types of WORM
types of non-volatile memory.
The testimony of both experts persuades us that a skilled artisan
would interpret “permanent storage memory” to cover non-volatile memory
that supports multiple write operations. Dr. Long equated the “permanent
storage” described in the ’717 Patent with a “disk” or “flash” memory.
Ex. 1026, 97:15–98:10. Dr. Konchitsky testified that a skilled artisan would
have considered “permanent storage memory,” which enables writing or
storing of information, to differ from “permanent memory,” which can only
be read after being written one time “in factory.” Ex. 2002 ¶ 21. The ability
to write data many times to permanent storage memory is consistent with the
way that “permanent storage memory” is used in the context of at least claim
6. Claim 6 recites a “caching computer further including a network cache
memory in its permanent storage memory.” The presence of cache memory,
which is likely to be written many times, in the “permanent storage
memory” implies a capability to write data many times to the claimed
“permanent storage memory.” Because claim terms are normally used
consistently throughout the patent, the usage of a term in one claim may
Cases IPR2012-00026 and IPR2013-00109
Patent 6,757,717
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illuminate the meaning of the same term in other claims. Phillips v. AWH
Corp., 415 F.3d 1303, 1314 (Fed. Cir. 2005). Therefore, we interpret
“permanent storage memory” to mean any non-volatile memory that
supports multiple write operations.
3. Sender/Computer and Receiver/Computer
Challenged claims 1, 3, 10, 11, 12, 14, and 22–24 recite either a
“sender/computer” or “receiver/computer” or both. Ex. 1002, col. 10, l. 31 –
col. 13, l. 8. Previously, we interpreted “sender/computer” to mean a
computer that sends data and “receiver/computer” to mean a computer that
receives data. ’026 Decision 14. We also concluded that each of these
respective computers can encompass multiple devices including
intermediaries. Id.
Proxyconn argues that our interpretation is “inconsistent with the ’717
Patent, is not the broadest reasonable interpretation of the claim terms, and
should be revised to exclude separate intermediate computers such as
gateways, proxies, routers, and caching computers.” Resp. 13. Proxyconn
contends that the Specification consistently refers to the sender and receiver
computers as separate devices.
Microsoft contends that we correctly interpreted the computers to
encompass multiple devices including intermediate devices. The
Specification represents the receiver and sender computers (46, 42
respectively) in decidedly schematic form, as shown in Figures 4, 11, and
14, reproduced below.
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Figure 4 illustrates receiver/computer 46 as a collection of functionally
defined subsystems 48, 52, and 54, which are described as follows: “[T]he
receiver/computer has calculating means 52 for calculating a digital digest
on data stored in its network cache memory 48. The receiver/computer also
has comparison means 54 for comparing between such a calculated digital
digest and a digital digest received from the network.” Ex. 1002, col. 7,
ll. 32–37.
The Specification appears to have one instance in which a computer is
described as being separate from or integral with another computer. The
Specification implies that gateway 60 and caching computer 62 may be
separate devices, but only by noting that “gateway computer 60 may be
integrally formed with the caching computer.” Ex. 1002, col. 9, ll. 6–8. The
Specification, along with the above figures, conveys to a skilled artisan that
the described computers, including the receiver/computer and the
sender/computer, may or may not be located in separate housings.
Accordingly, Proxyconn has not persuaded us to modify the original
interpretation of “receiver/computer” and “sender/computer.”
4. Gateway . . . Between at Least Two Other Computers
Independent claims 6 recites a “gateway . . . connected to said packet-
switched network in such a way that network packets sent between at least
two other computers pass through it.” Ex. 1002, col. 10, l. 66 – col. 11, l. 2.
Claims 7 and 9, which depend upon claim 6, also include the “gateway” and
“two other computers.” Id. at col. 11, ll. 13–20. Proxyconn asserts that
“two other computers” refers to “the sender/computer and the
receiver/computer.” Resp. 15 (citing Ex. 1002, col. 2, ll. 44–47). The cited
portion of the Specification, however, merely recites verbatim the language
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of claim 6 relating to the gateway and two other computers. Therefore, the
cited portion has not been shown to support Proxyconn’s contention.
Microsoft contends that no such limitation exists on the “two other
computers” and that these computers may be any two other computers
connected on the network to the gateway. See ’109 Petition 13–14,
Appendix A 5–6.
We agree with Microsoft. Claim 6 plainly and unambiguously recites
“two other computers” as a limitation on the manner in which the “gateway”
is “connected to said packet switched network.” That is, the gateway is
connected to the network so that “network packets sent between at least two
other computers pass through it [i.e., the gateway].” Applying the broadest
reasonable interpretation, we conclude that claim 6 does not limit which
computers may constitute the “two other computers” between which the
gateway is connected.
5. Means for comparison between digital digests
a. Claims 1 and 3
Claim 1 recites “means for comparison between digital digests.”
Resolution of the parties’ arguments relating to whether Yohe anticipates
claims 1, 3, and 10 requires that we interpret “digital digests” as recited in
the comparison means. We interpret “digital digests” by reading claim 1 in
its entirety. Claim 1 recites that both the sender and receiver include “means
for creating digital digests on data.” We conclude that the “digital digests”
recited in the means for comparison refers to the “digital digests on data”
that are recited earlier in claim 1 in the “means for creating.”
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b. Claim 10
Claim 10, like claim 1, recites that the receiver includes “means for
comparison between digital digests.” Also like claim 1, claim 10 recites that
the sender includes a “means for creating digital digests on data.” By
contrast to claim 1, claim 10 does not recite a “means for creating” in the
receiver. Ex. 1002, col. 11, ll. 20–33. Instead, the receiver includes a
“means for storing a digital digest received from said network.” Id. at
col. 11, ll. 31–32 (emphasis added). The reference to “a digital digest”
rather than “the digital digest on data” in the storing means implies that the
receiver can store any type of digital digest received from the network.
Therefore, the “digests” that are compared in the “means for
comparison” recited in claim 10 need not be the two digests on data created
by the sender and receiver. Instead, the “means for comparison between
digital digests” recited in claim 10 refers to structure that can compare any
digital digest received from the network with any other digital digest.
6. Searching for Data with the Same Digital Digest
Claims 22–24 recite a step of “searching for data with the same digital
digest.” Proxyconn argues that the “searching” step requires the capability
to identify particular data “with the same digital digest” from among a set of
data that potentially contains multiple items. See Resp. 6, 20–21 (attempting
to distinguish claims 22–24 from Perlman), 27–28 (attempting to distinguish
claims 22 and 23 from Yohe), 35–36 (attempting to distinguish claim 23
from Santos). Microsoft contends that the ’717 Patent equates “search” with
“check for” and that the Specification never describes any “search” method
other than “comparing two digest values for a match.” MS Reply 4.
Microsoft asserts that the recited step of “searching for data with the same
Cases IPR2012-00026 and IPR2013-00109
Patent 6,757,717
20
digital digest,” merely requires comparing a digest for a data object received
from the network with a digest of the receiver’s copy of that data object. Id.
at 5.
The Specification never expressly defines “search.” Nonetheless, the
plain meaning of “search” is: “to look into or over carefully or thoroughly in
an effort to find or discover something.” MERRIAM WEBSTER’S COLLEGIATE
DICTIONARY 1053 (10th ed. 1999). Two dictionaries in the relevant field of
computing technology define “search” as it would be understood by a skilled
artisan as follows:
1. “To scan one or more data elements of a set in order to find elements
that have a certain property,” IBM DICTIONARY OF COMPUTING 600
(10th ed. 1993); and
2. “(information processing). To examine a set of items for those that
have a desired property,” IEEE STANDARD DICTIONARY OF
ELECTRICAL AND ELECTRONICS TERMS 808 (3d ed. 1984).
These dictionary definitions reflect that a skilled artisan would have
understood “search” to involve analyzing a set of items to identify one
particular item from among a set of items. A “set” refers to “a number of
things of the same kind that belong or are used together,” MERRIAM
WEBSTER’S COLLEGIATE DICTIONARY 1071 (10th ed. 1999), or “[a] finite or
infinite number of objects of any kind, of entities, or of concepts that have a
given property or properties in common,” IBM DICTIONARY OF
COMPUTING 618 (10th ed. 1993). While a set can contain one item, a
“search” for a desired member of a “set” requires a capability to examine
more than one item to identify a particular item within that set. Therefore,
we conclude that “searching for data with the same digital digest in said
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Cases IPR2012-00026 and IPR2013-00109
Patent 6,757,717
22
include “storage locations typically composed of random access memory
(RAM) devices.” Id. at col. 5, ll. 40–47.
Packetized data is transmitted across the network with each packet
having the address of its final destination and the address of the next node to
which it will travel along the route to the final destination. Id. at col. 5, l. 65
– col. 6., l. 1. The final destination address remains constant, but the “next
destination” address changes as the packet moves from node to node in the
network. Id. at col. 6, ll. 1–4. Upon arrival of a packet to a router, the router
determines the next destination address of the packet based on algorithms to
calculate a path to the final destination. Id. at col. 6, ll. 5–24. For this mode
of transmission to work, every router must determine and communicate its
location in the network to other nodes on the network. Id. at col. 6, ll. 25–
45. These network “maps” must be synchronized to ensure that data packets
arrive at the correct final destination. Id. at col. 6, ll. 46–53.
Perlman synchronizes these network maps by having one designated
router (e.g., R4) periodically calculate and send a digest of that map (called a
“complete sequence numbers packet” or CSNP) to all other routers on the
network. Id. at col. 6, l. 47 – col. 7, l. 55. When each of the other routers
receives the CSNP digest from R4, each of those routers compares that
received CSNP digest to a digest of the network topology calculated locally
by the receiving router. Id. at col. 7, ll. 56–63.
Perlman also describes an “alternate embodiment” in which “high-
level and low-level identifiers are bundled within the same hello message
that is periodically broadcast by the designated router, R4 to the other
routers.” Id. at col. 8, ll. 25–28. For this embodiment, the receiving router
first compares its locally generated high-level digest with received high-
Cases IPR2012-00026 and IPR2013-00109
Patent 6,757,717
23
level digest 710. Id. at col. 8, ll. 32–35. If the two digests are not the same,
then the receiving router calculates low-level digests for fragments of its
database and compares each of these low-level digests with corresponding
received low-level digests 725a–c. Id. at col. 8, ll. 36–39. Based on these
comparisons, the receiving router determines which fragments of its
database require updating. Id. at col. 8, ll. 39–42.
2. Yohe
Yohe generally describes an “apparatus for increased data access in a
network [that] includes a file server computer having a permanent storage
memory, [and] a cache verifying computer operably connected to the file
server computer in a manner to form a network for rapidly transferring
data.” Ex. 1005, Abstract. Yohe’s Figure 2, reproduced below,
schematically illustrates the configuration of the data access network.
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Similarly, Yohe’s file server computer also expressly includes a
processor, operating system, memory, and permanent storage memory. Id.
at col. 3, ll. 22–24. The file server computer is “operably connected” to
cache verifying computer 14, which includes “means for performing an
operation on data stored in the permanent storage memory of the file server
computer to produce a signature of the data characteristic of one of a file and
directory.” Id. at col. 2, ll. 43–51. Yohe describes two means for producing
a signature, or digest, block signature generator 56 and directory signature
generator 57. Id. at col. 5, ll. 14–17.
Yohe describes cache verifying computer 14 as having an operating
system, a first memory, and a processor. Id. at col. 2, ll. 46–47. Cache
verifying computer 14 incorporates cache verifying agent 54 consisting of
block signature generator 56, directory signature generator 57, and
comparator 58. Id. at col. 5, ll. 14–17. The cache verifying computer is also
“operably connected” to the file server computer so that block signature
generator 56 can create digests for data files stored in permanent storage 80.
Id. at col. 2, ll. 43–51.
Yohe’s client computer and the cache verifying computer thus each
have capability to generate digests for data stored on the client and file
server respectively. When Yohe’s client computer requests data (e.g., to
read a file stored in permanent storage on the file server), it generates a read
request with an embedded digest and sends that request to the cache
verifying computer. The cache verifying computer generates a digest for the
requested file as that file exists in the permanent storage memory of the file
server. The cache verifying computer then compares the two digests to
determine whether the files stored on the remote client and file server are the
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same. If not, the file server’s version is sent to the remote client. If so, the
remote client uses its locally stored version of the file. Id. at col. 6, ll. 22–
37; figs. 6 and 7.
Yohe does not compare any particular received digest with more than
one locally generated digest. Yohe describes two types of comparators for
analyzing two versions of a digest. The first is comparator 58 in cache
verifying computer 14, which compares digests for data files. Id. The
second is directory signature comparator 46 in remote client 12, which
compares one-by-one a series of digests for directory sub-objects that are
received from the cache verifying computer with the locally generated
digests for corresponding directory sub-objects. Id. at col. 7, l. 6 – col. 8,
l. 25 (describing steps performed in DIRECTORY REQUEST function as
shown in Figures 15 and 16).
3. Santos
Santos describes a compression architecture that prevents
transmission of replicated data to increase bandwidth in a packet switched
environment such as the Internet. Ex. 1004, 2. The bandwidth savings is
achieved by transmitting repeated data as a short dictionary token, using
caches of recently-seen data at both ends of the link to maintain the
dictionary, and encode and decode the tokens. Id. at 5. The approach of
Santos is based on the insight that the “fingerprint” of a data segment is an
inexpensive name for the data itself, both in terms of space and time. Id.
Santos uses the MD5 hash algorithm for his implementation, but states that
other “fingerprints” could be used. Id. Figure 4 of Santos is reproduced
below:
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Cases IPR2012-00026 and IPR2013-00109
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machines with 128 MB of RAM and a cache of 200 MB running a Linux
operating system. Id. at 9.
4. DRP
DRP describes a protocol for improving the efficiency and reliability
of data distribution over HTTP. DRP, 2, ll. 12–13. One of the goals is to
avoid downloading the same data more than once. Id. at 2, ll. 29–30. The
protocol described in DRP makes use of content identifiers based on
checksum technology. Id. at 2, ll. 37–39. A content identifier can be used
uniquely to identify each piece of data or content and to determine whether
two pieces of content are identical. An example of a checksum algorithm
that can be used for this purpose is the MD5 message digest algorithm. Id.
at 3, ll. 24–25.
To describe the exact state of a set of data files, DRP uses a data
structure called an index. Id. at 4, l. 37. An index is a snapshot of the state
of a set of files at a particular moment in time. It is typically stored in
memory as a data tree structure, but to enable clients and servers to
communicate this information over HTTP, an index can be described using
XML. Id. at 4, ll. 39–42.
A DRP index is retrieved by giving a uniform resource locator
(“URL”) to the index. Id. at 5, l. 22. The index can be stored in any file and
can be retrieved using a normal HTTP GET request. Id. at 5, ll. 22–23.
Once the initial download is complete, a client can update content by
downloading a new version of the index and comparing it against the
previous versions of the index. Because each file entry in the index has a
content identifier, the client can determine which files have changed and,
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thus, determine the minimal set of files that need to be downloaded in order
to bring the client up to date. Id. at 5, ll. 31–33.
An HTTP header field called Content-ID is used to specify the current
correct version of the file that is requested by the client. The server can use
the content identifier in the Content-ID field to determine if the requested
version of the file can be delivered to the client. Id. at 7, ll. 30–32. If no
content identifier is specified in the HTTP GET request, the server returns
the current version of the file. Id. at 7, ll. 37–38. When a file is updated on
the server, it will be downloaded by each of the clients that needs the new
version. Id. at 8, ll. 3–4.
DRP notes that updates to files very often affect only small portions of
the file, and it would therefore be much more efficient if the server could
reply with only the parts of the file that have changed. Id. at 8, ll. 4–5. This
is achieved using a “differential” GET request. When a file is modified, the
client can issue a differential GET request for the file, which includes not
only the content identifier of the desired version of the file, but also the
content identifier of the current version of the file on the client. Id. at 8,
ll. 11–13. In a differential GET request the content identifier of the file as it
exists on the client is specified using the Differential–ID field in the HTTP
header. Id. at 8, ll. 14–15. When the server receives a GET request that
includes a Differential–ID field, it can look in its file cache for both versions
of the requested file, using the content identifiers specified in the Content–
ID field and the Differential–ID field. If both versions of the file are found,
the server can compute the difference between the two files and return the
difference, rather than the entire file. Id. at 8, ll. 25–28. If the server does
not have access to the version of the file that is indicated by the differential
Cases IPR2012-00026 and IPR2013-00109
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content identifier, it can ignore the differential content identifier and return
the entire requested file. Id. at 8, ll. 32–33.
DRP also describes the use of proxy caching. In this application, an
HTTP proxy can be made aware of the Content–ID and Differential–ID
fields in HTTP requests and replies. Id. at 9, ll. 38–39. Because the content
identifier is included in each GET request, the proxy can avoid accidentally
returning the wrong version of the requested file. Id. at 9, ll. 39–40. The
proxy can use the content identifier field to identify uniquely the content
being transferred as the same content is likely to have the same content
identifier, even when downloaded from multiple locations. The proxy can
thus use this information to avoid multiple downloads. Id. at 9, ll. 43–45.
The proxy can also use the Differential–ID header field to reply to
differential GET requests. If both versions of the file are in the proxy’s
cache, the proxy can provide the differential reply. Id. at 10, ll. 1–2.
5. Mattis
According to Mattis, a key factor limiting the performance of the
World Wide Web is the speed with which servers can supply information to
clients via the Internet. Mattis, col. 1, ll. 53–55. Accordingly, client
transaction time can be reduced by storing replicas of popular information
objects in repositories geographically dispersed from the server. Each local
repository for object replicas is generally referred to as a cache. Id. at col. 1,
ll. 58–62. In some arrangements, the cache is located in a proxy server that
is logically interposed between clients and the server. The proxy server is a
“middleman gateway,” acting as a server to the client, and the client to the
server. Id. at col. 1. 66 to col. 2, l. 3. A proxy server equipped with a cache
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is called a “caching proxy server,” or just a “proxy cache.” Id. at col. 2,
ll. 3–5.
The proxy cache intercepts requests for resources that are directed
from clients to the server. When the cache in the proxy has a replica of the
requested resource that meet certain constraints, the proxy responds to the
clients and serves the resources directly. Id. at col 2, ll. 6–11. In this
arrangement, the number and volume of data transfers along the links are
greatly reduced. As a result, network resources or objects are provided more
rapidly to the clients. Id. at col. 2, ll. 11–14.
Mattis uses a “fingerprint” of the content that makes up the object
itself to locate the object. Id. at col. 8, ll. 18–21. Specifically, the object key
is a unique “fingerprint” or compressed representation of the contents of the
object. A copy of the object is provided as an input to a hash function (e.g.,
MD5) and its output is the object key. Given a content fingerprint key, the
content can easily be found in the cache. Id. at col. 8, ll. 23–36. In some
embodiments of Mattis, for each of the objects, the cache also creates a
name object key. The name key is created by applying a hash function to
the name of the object. Id. at col. 8, ll. 55–58. Mattis recognizes that
requests for objects typically identify requested objects by name, such as a
URL, file system name, or network address. Id. at col. 9, l. 65 to col. 10,
l. 4.
In one embodiment of Mattis, a lookup operation is used to determine
whether a particular object identified by particular name is stored currently
in the cache. See id. at fig. 9A. When the process is applied in the context
of the World Wide Web, the name is a URL. Id. at col. 27, ll. 61–62. The
cache converts the name of the object to a key value by passing the object
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name or URL to hash function such as MD5. Id. at col. 27, ll. 63–67. The
key is checked against a directory, and if the requested object is found, it is
retrieved from storage and sent to the client. Id. at col. 28, ll. 10–14. If the
object is not found in storage, the cache obtains a copy of the object from the
appropriate server. Id. at col. 28, ll. 43–47.
C. Patentability of Original Claims
To prevail in its challenges to the patentability of claims, the
petitioner must establish facts supporting its challenges by a preponderance
of the evidence. 35 U.S.C. § 316(e); 37 C.F.R. § 42.1(d).
1. Anticipation
The Court of Appeals for the Federal Circuit summarized the
analytical framework for determining whether prior art anticipates a claim as
follows:
If the claimed invention was “described in a printed
publication” either before the date of invention, 35 U.S.C.
§ 102(a), or more than one year before the U.S. patent
application was filed, 35 U.S.C. § 102(b), then that prior art
anticipates the patent. Although § 102 refers to “the invention”
generally, the anticipation inquiry proceeds on a claim-by-claim
basis. See Hakim v. Cannon Avent Group, PLC, 479 F.3d 1313,
1319 (Fed. Cir. 2007). To anticipate a claim, a single prior art
reference must expressly or inherently disclose each claim
limitation. Celeritas Techs., Ltd. v. Rockwell Int’l Corp., 150
F.3d 1354, 1361 (Fed. Cir. 1998). But disclosure of each
element is not quite enough—this court has long held that
“[a]nticipation requires the presence in a single prior art
disclosure of all elements of a claimed invention arranged as in
the claim.” Connell v. Sears, Roebuck & Co., 722 F.2d 1542,
1548 (Fed. Cir. 1983) (citing Soundscriber Corp. v. United
States, 175 Ct.Cl. 644, 360 F.2d 954, 960 (1966) (emphasis
added)).
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Finisar Corp. v. DirecTV Grp., Inc., 523 F.3d 1323, 1334–35 (Fed. Cir.
2008). We must analyze prior art references as a skilled artisan would. See
Scripps Clinic & Res. Found. v. Genentech, Inc., 927 F.2d 1565, 1576 (Fed.
Cir. 1991) (to anticipate, “[t]here must be no difference between the claimed
invention and the reference disclosure, as viewed by a person of ordinary
skill in the field of the invention”).
For the reasons expressed below, Microsoft has demonstrated by a
preponderance of evidence that Yohe anticipates claim 10; Santos
anticipates claims 1, 3, 22, and 23; and DRP anticipates claims 6, 7, 9, 11,
12, and 14. Microsoft has failed to establish by a preponderance of evidence
that Perlman and Yohe anticipate any of the remaining challenged claims.
a. Perlman
(1) Claims 1 and 3
Proxyconn argues that Perlman does not anticipate claims 1 and 3
because Perlman fails to disclose “permanent storage memory,” but instead
uses random access memory (“RAM”). Resp. 18 (citing Ex. 1003, col. 5,
ll. 46–48)). Microsoft counters that Perlman describes permanent storage
memory in the form of memory for storing an operating system. ’026
Petition 17 (citing Ex. 1002, col. 5, ll. 41–52, fig. 2). We see no express
statement in the cited portion of Perlman that its computers include any type
of memory other than RAM. ’026 Petition 17 (citing Ex. 1007, 12:5–17).
Microsoft relies upon the Declaration of Darrell D. E. Long, Ph.D. Dr. Long
opines, without explanation, that a skilled artisan would understand Perlman
to disclose an “illustrative-embodiment router [that] is a ‘general-purpose’
computer . . . having, among other things, a hard disk or the like for storing
Cases IPR2012-00026 and IPR2013-00109
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persistently data and application programs.” Ex. 1007, 12:7–12 (citing
Perlman, Ex. 1003, col. 5:41–52, fig. 2). However, Dr. Long also testified:
Q. So your testimony is that each and every limitation of
claim one is disclosed in Perlman, correct?
A. We’ve got a computer — there may be — I’d have to
go back and study Perlman. Maybe we don’t mention
permanent storage, whatever that means.
Q. Okay.
A. Okay. Although, certainly that’s — I would consider
that a triviality.
Q. Okay.
A. Okay. Digest, that’s there. That’s there.
Comparisons are there. Maybe permanent memory is missing.
Ex. 1026, 172:10–22. When asked specifically how Perlman describes
“permanent storage memory,” Dr. Long responded, “I thought [Perlman]
talked about flash in here. Certainly, it’s something that a router can have
and router[s] can and do have.” Ex. 1026, 149:4–9. However, Dr. Long
failed to identify how Perlman expressly discloses permanent storage
memory. Based on his testimony, we conclude that a skilled artisan would
understand Perlman to disclose routers that may or may not have permanent
storage memory.
A finding of anticipation by inherency requires more than
probabilities or possibilities. Motorola Mobility LLC v. Int’l Trade Comm’n,
737 F.3d 1345, 1350 (Fed. Cir. 2013). Based on the evidence discussed
above, it is possible to infer that Perlman describes such permanent storage
memory. However, Microsoft has not presented evidence that the computers
or routers described by Perlman necessarily use permanent storage memory
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as recited in claims 1 and 3. Therefore, Microsoft has failed to establish by a
preponderance of evidence that Perlman describes a receiver/computer or
sender/computer necessarily having “permanent storage memory.” Without
such evidence, we cannot conclude that Perlman anticipates claims 1 and 3.
(2) Claims 22–24
Proxyconn contends that Perlman fails to disclose the step recited in
independent claim 22 of “searching for data with the same digital digest in
said network cache memory.” Resp. 20. Instead, Proxyconn urges that
Perlman stores “one database identifier” that is merely “compared to the
identifier received from the designated router.” Id.; see also Ex. 2007, 13
(citing Ex. 1003, col. 8, ll. 32–42). Dr. Konchitsky testified, without citing
any particular portion of Perlman, that Perlman’s “receiving routers receive
an identifier and each simply compares the received identifier with its
existing identifier. The receiving routers are not searching for data files
using the identifier as the key, or among multiple identifiers.”
Ex. 2002, ¶ 23.
Microsoft cites numerous passages from Perlman as meeting the
recited “searching” step. ’026 Petition, App’x. A, 17. All but one of the
cited passages from Perlman describes the comparison of a received high-
level database digest with a locally calculated high-level database identifier.
The other cited passage (Ex. 1003, col. 8, ll. 22–49) describes an alternate
embodiment in which received low-level digests are compared to locally
generated low-level digests, if the received and locally generated high-level
digests do not match. See part II.B.1 above (describing Perlman’s use of
high-level and low-level digests).
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We conclude that Microsoft has failed to establish by a preponderance
of evidence that Perlman meets the “searching” step recited in claim 22.
Every portion of Perlman upon which Microsoft relies involves comparing
one received digest to a corresponding locally calculated digest. These one-
to-one comparisons cannot identify a particular data object from among a set
of data objects as required by the “searching” step. Rather, the comparisons
reveal whether a locally stored data object is synchronized with the
corresponding remotely stored data object. Claims 23 and 24 depend from
claim 22. We therefore, conclude that Perlman does not anticipate claims
22–24.
b. Yohe
(1) Claims 1, 3, and 10
Proxyconn first argues that Yohe fails to describe a sender/computer
having permanent storage memory and means for creating digital digests of
data. Resp. 21–23. Microsoft counters that the combination of Yohe’s
cache verifying computer 14 and file server 18 constitutes the claimed
sender/computer. ’026 Petition 16, App’x. A, 3; MS Reply 5–6; see also
Ex. 1028, 16 (regarding annotated version of Yohe, Figure 2). We reject
Proxyconn’s argument because claims 1, 3, and 10 do not limit
“sender/computer” to hardware residing in one housing. We have concluded
that “sender/computer” may broadly encompass “multiple devices,” and
Proxyconn has directed us to no persuasive evidence that our interpretation
is incorrect.
Proxyconn next argues that Yohe fails to describe a
“receiver/computer” with means for creating digital digests on data.
Resp. 23–24. Microsoft identifies Yohe’s block signature generator 44 in
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remote client computer 12 as the recited “means for creating digital digests
on data.” ’026 Petition 20, App’x. A, 9; see also Ex. 1028, 13 (regarding
annotated version of Yohe, Figure 2). We agree with Microsoft that Yohe’s
block signature generator 44 creates digests on data stored in Yohe’s cache.
Ex. 1005, col. 6, ll. 22–23.
Proxyconn also argues that Yohe fails to describe a
“receiver/computer” with means for comparing received and locally
generated digital digests on data. Resp. 24; see also Ex. 2007, 18–19
(regarding annotated version of Yohe, Figure 2). Proxyconn contends that
comparator 58, which is part of cache verifying computer 14 and not remote
client 12, compares the digests generated by block signature generators 44
and 56. Ex. 2007, 19 (annotating Yohe’s Figure 2); see also Tr. 55:1–8
(identifying Ex. 1005, Yohe, col. 6, ll. 22 to col. 7, ll. 16 as confirming
annotations on Yohe’s Figure 2). Microsoft identifies Yohe’s directory
signature comparator 46 in remote client computer 12 as the recited “means
for comparison between digital digests” that compares the digital digests on
data that were separately created by the sender and receiver computers. ’026
Petition 21, App’x. A, 10; see also Ex. 1028, 13 (regarding annotated
version of Yohe, Figure 2).
We agree with Proxyconn that Yohe fails to describe a
“receiver/computer including means for comparison of digital digests” as
recited in claims 1 and 3. The two versions of digests on data that Yohe
generates via block signature generators 44 and 56 are compared by
comparator 58, which is not a component of remote client 12. For this
reason, we conclude that Microsoft has not established by a preponderance
of evidence that Yohe anticipates claims 1 and 3.
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However, claim 10 does not require that the “means for comparison
between digital digests” refers to comparing a digest generated by the
receiver to a digest generated by the sender. See Part II.A.5.b above.
Instead, we have concluded that the “means for comparison between digital
digests” recited in claim 10 refers to structure that can compare any digital
digest received from the network with another digital digest. Yohe’s remote
client 12 includes directory signature comparator 46 that compares a
directory signature received from the cache verifying agent 54 (i.e., a portion
of a sender/computer), with a directory signature retrieved from the remote
client’s cache. Ex. 1005, col. 8, ll. 5–11. Therefore, we agree with
Microsoft that Yohe’s directory signature comparator 46 is a “means for
comparison between digital digests” as recited in claim 10. We determine
that Microsoft has established by a preponderance of evidence that Yohe
anticipates claim 10.
(2) Claims 6 and 7
Proxyconn argues that Yohe fails to describe a caching computer
having network cache memory in its permanent storage memory as required
in claims 6 and 7. Microsoft contends that permanent storage device 80,
shown as part of Yohe’s file server 18, constitutes the “permanent storage
memory” of the claimed caching computer. ’109 Petition 17, App’x. A,10.
Essentially, Microsoft argues that the combination of Yohe’s cache verifying
computer 14 and file server 18 meet all the recited limitations for the
caching computer of claim 6. Proxyconn contends that even if we were to
agree that cache verifying computer 14, file server 18, and permanent
storage device 80 were the claimed “caching computer,” this combination
still fails to describe network cache memory in the permanent storage
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memory. Resp. 26–27. Microsoft fails to address this argument in its reply.
See MS Reply 9. Our review of Yohe fails to identify any description of a
network cache memory in permanent storage device 80. For this reason, we
conclude that Microsoft has not established by a preponderance of evidence
that Yohe anticipates claim 6 or its dependent claim 7.
(3) Claims 22 and 23
Proxyconn argues that Yohe fails to disclose the step recited in
independent claim 22 of “searching for data with the same digital digest in
said network cache memory.” Resp. 27–28. Proxyconn contends that the
only analysis of digests performed by Yohe’s receiver (i.e., the remote
client) is performed by Yohe’s directory signature comparator 46, which
compares one directory digest with a digest received from the cache
verifying computer. Id. at 27. Proxyconn argues that such one-to-one
comparisons are not “searching” as recited in claim 22. Id. at 27–28.
Microsoft does not dispute Proxyconn’s characterization of the
manner in which Yohe’s directory signature comparator operates. MS
Reply 11. Rather, Microsoft contends that Proxyconn’s position is
predicated on a flawed interpretation of “search” that requires more than a
“single-comparison search.” Id.
Based on our review of Yohe, the directory signature comparator 46
performs, at most, a series of one-to-one comparisons of received digests to
locally generated digests for directory sub-objects. Ex. 1005, col. 7, l. 6 –
col. 8, l. 25 (describing steps performed in DIRECTORY REQUEST
function as shown in Figures 15 and 16). We conclude that such one-to-one
comparisons do not identify a particular directory sub-object from among a
set of directory sub-objects as required by the “searching” step. Rather, the
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comparisons simply reveal whether a locally stored directory sub-object is
synchronized with the corresponding remotely stored directory sub-object.
Claim 23 depends from claim 22. We therefore conclude that Microsoft has
not established by a preponderance of evidence that Yohe anticipates claims
22 and 23.
c. Santos
(1) Claims 1 and 3
Proxyconn raises two arguments allegedly distinguishing claims 1 and
3. We address each in turn below.
First, Proxyconn argues that Santos fails to describe a
receiver/computer. Resp. 33–34. Proxyconn contends that Santos describes
“a compressor and a decompressor, which are intermediate computers.” Id.
at 33. Microsoft counters that Proxyconn’s argument rests upon an incorrect
interpretation of “receiver/computer.” We agree. We have interpreted
“receiver/computer” to refer to “a computer that receives data.” Santos’s
two computers on opposite ends of the communication channel can send and
receive data. See Ex. 1004, 6 (stating that “[b]idirectional compression is
achieved by using two instances of the protocol, one for each direction.”)
Thus, Santos uses “compressor” and “decompressor” to denote the function
performed by each of two computers during transmission of specific data in
a specific direction across the communication channel between them.
Because data can move in both directions across that channel, both machines
may function as a compressor (i.e., sender) or a decompressor (i.e.,
receiver). In the context of claims 1 and 3, the decompressor is acting as a
“receiver/computer.” We therefore reject Proxyconn’s first argument.
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Second, Proxyconn argues that Santos fails to describe “means for
creating a digital digest on data in the network cache memory.” Resp. 35.
Proxyconn contends that because Santos’s compressor and decompressor
calculate the digest for data after the data is received but before the data is
stored, the calculation of the digest is not on data in the network cache
memory. Id. Proxyconn’s argument rests upon an inferred interpretation of
the creating means that requires a specific order of operations. More
specifically, Proxyconn argues that “creating a digital digest on data in the
network cache memory” implicitly requires that the receiver first read data
from the network cache memory and then create a digest for that data.
Microsoft counters that claims 1 and 3 “do not require that the
receiver first read the data from the cache and then and only then calculate a
digest on it.” MS Reply 8. Microsoft’s argument also rests upon an inferred
interpretation of the creating means. More specifically, Microsoft infers that
the receiver’s creating means need only be capable of creating a digest
corresponding to data that is or will be stored in the network cache memory.
We conclude that Microsoft’s interpretation is more consistent with
the broadest reasonable interpretation of “means for creating digital digests
on data in said network cache memory.” Claim 1 and its dependent claim 3
recite systems, not methods, with hardware having recited functional
capabilities. The functional language in claim 1 is not limited to a particular
order of operations. “[A]pparatus claims cover what a device is, not what a
device does. An invention need not operate differently than the prior art to
be patentable, but need only be different.” Hewlett-Packard Co. v. Bausch
& Lomb Inc., 909 F.2d 1464, 1468 (Fed. Cir. 1990); see also Roberts v.
Ryer, 91 U.S. 150, 157 (1875) (“The inventor of a machine is entitled to the
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benefit of all the uses to which it can be put, no matter whether he had
conceived the idea of the use or not.”). Here, the receiver/computer must be
capable of creating a digest on data that is “in” the receiver’s network cache
memory.
We find that Santos describes a computer that can calculate a digest
on data corresponding to data that will be stored in the receiver’s network
cache. When data not yet in Santos’s compressor’s cache is to be sent across
the communication channel, Santos’s compressor sends that data to the
decompressor. Ex. 1004, 7. Santos’s decompressor, upon receiving the data
also creates a digest for that data and stores the digest and the data in the
decompressor’s cache. Id. Santos describes this case as follows:
When the compressor receives a packet {HdrA, X} [i.e.,
data] to be forwarded over the link, where HdrA is the TCP/IP
header and X is the data payload, it first computes H(X) [i.e., a
digest], the fingerprint of X. If it finds that no entry indexed by
H(X) [digest] exists in its cache, it stores X in its cache,
indexed by H(X) [digest]. It then forwards the TCP/IP packet
across the link. Upon receiving a TCP/IP packet forwarded
over the channel, the decompressor also computes H(X)
[digest], and stores X in its cache, indexed by H(X) [digest].
The TCP/IP packet is then output from the system.
Ex. 1004, 7, Figure 4.
Santos’s decompressor thus calculates a digest for every data payload
that it receives from the compressor and stores that data payload and its
digest in its network cache memory. Ex. 1004, 7–8. We therefore reject
Proxyconn’s second argument and find that Santos describes a
receiver/computer that includes “means for creating digital digests on data in
said network cache memory.” We determine that Microsoft has established
by a preponderance of evidence that Santos anticipates claims 1 and 3.
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(2) Claim 10
Proxyconn contends that Microsoft never challenged the patentability
of claim 10 as anticipated by Santos and that our decision to institute a trial
on this ground was “a mistake.” Resp. 32–33, n.5. For this reason,
Proxyconn never substantively addresses Santos as it relates to claim 10. Id.
at 32–33. However, Microsoft’s claim charts compared claim 10 to Santos.
’026 Petition, App’x. A 11–13. That claim chart is part of Microsoft’s
petition, and we instituted review of claim 10 as anticipated by Santos on the
grounds raised in the claim chart. Microsoft has thus proffered evidence to
establish that Santos describes every limitation of claim 10. Proxyconn fails
to rebut Microsoft’s evidence. In the absence of countervailing evidence
and argument, we determine that Microsoft has established by a
preponderance of evidence that Santos anticipates claim 10.
(3) Claim 22
Claim 22 is directed to a method “performed by a receiver/computer.”
Ex. 1002, col. 12, ll. 30–31. Just as with claims 1 and 3, Proxyconn argues
that Santos fails to describe a “receiver/computer.” Resp. 33–34. For the
same reasons described above in connection with claims 1 and 3, we find
that Santos describes the claimed receiver/computer. Microsoft has
proffered evidence to establish that Santos meets every other limitation of
claim 22, and Proxyconn fails otherwise to rebut that evidence. Therefore,
we determine that Microsoft has established by a preponderance of evidence
that Santos anticipates claim 22.
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(4) Claim 23
Proxyconn argues that Santos fails to describe “searching in
predetermined locations of said permanent storage memory for data” for two
reasons. Resp. 35–36. First, Proxyconn argues that Santos “lacks
permanent storage memory,” which is evident from the loss of “fingerprints
H(X) and associated data” when Santos’s computers are reset. Id. at 35
(citing “Ex. 1004 at § 3.2.1”).4 Proxyconn contends “[i]f either the data
payload or fingerprints H(x) were stored in permanent storage memory, the
data and fingerprint H(x) would be retained in memory, following either a
reset or power cycle.” Resp. 35–36.
In response, Microsoft characterizes Santos’s compressor and
decompressor as “general-purpose” computers that “necessarily” have ROM
and a hard disk. MS Reply 11. Microsoft also contends that Santos’
description of a 200 MB cache in a system with only 128 MB RAM implies
that some cache must be in non-volatile memory. Id. (citing Ex. 1004, 7–9
and Figures 4 and 5). Microsoft does not directly address Proxyconn’s
contention that the loss of data in Santos’s cache upon a reset demonstrates
that Santos’s cache does not reside in permanent storage memory.
Based on our own review of Santos, we reject Proxyconn’s argument
as not being supported by the evidence. Santos’s only description of a reset
relates to a “reset message” rather than a system reset or power interruption.
Ex. 1004, 7 and 9. Santos describes using a reset message sent from the
compressor to the decompressor or vice versa as a mechanism for handling a

4 The cited portion of Santos does not address the effect of a “reset.”
Nonetheless, Santos describes a reset process elsewhere. Ex. 1004, 9 (in
§ 3.3).
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lack of synchronization between the caches in each machine. Id. at 9. We
understand these reset messages to be sent intentionally to reset the other
cache to a known state in the event that the stored information about “illegal
fingerprints” is lost (e.g., due to a compressor restart). Id. Santos does not
describe where or how the compressor stores information relating to illegal
fingerprints. Thus, we find Proxyconn’s cited evidence to be inconclusive
regarding the character of the cache memory.
Microsoft’s evidence on the nature of the cache memory is more
persuasive. Santos describes its compressor and decompressor in some
detail as being “Intel-based Pentium II 300 MHz machines running Linux
2.0.31 with 128 MB of RAM.” Ex. 1004, 9. Santos also states: “we limited
the amount of memory available for the caches, . . . , to 200 MB each.” Id.
Santos also expressly describes repeated and numerous write operations to
the cache. Ex. 1004, Figures 4 and 5 and accompanying text at 7–8.
We are persuaded that a skilled artisan would understand that Santos’s
200 MB cache, which exceeds the available RAM in each machine, referred
to a non-volatile memory that supports multiple write operations, which
satisfies our interpretation of “permanent storage memory.” We therefore
reject Proxyconn’s argument that Santos does not describe “permanent
storage memory.”
Second, Proxyconn argues that Santos fails to “search in
predetermined locations” within the permanent storage memory. Resp. 36.
Proxyconn asserts that “[s]earching in an index or files stored in memory is
far different than searching at a predetermined location in memory, much
less in predetermined locations in permanent storage memory.” Id. The sole
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support that Proxyconn provides for this assertion is the following testimony
of Dr. Konchitsky.
51. I understand Santos to disclose that the fingerprints
are not stored in permanent storage memory. Santos states that
upon reset, such as through a power cycle or restart, the
fingerprints H(x) and associated data is lost. [EX1004] at §3.3.
This indicates to me, as it would to any person of ordinary skill
in the art[,] that the fingerprints are not stored in permanent
storage memory, and thus Santos could not logically teach
searching permanent storage memory for fingerprints.
Ex. 2002 ¶ 51, Resp. 36. Dr. Konchitsky’s testimony does not support
Proxyconn’s assertion that Santos searches “in predetermined locations” in
memory. Rather, Dr. Konchitshy’s testimony relates to whether Santos
describes “permanent storage memory.”
Microsoft responds that Santos “looks in at least two predetermined
locations: it looks at H(X) and then, to identify any collisions, it looks at the
stored payload associated with the H(X) and compares that to the argument
payload.” MS Reply 11 (citing Ex. 1004, 7–9, Figures 4 and 5). We
determine that the evidence cited by Microsoft is persuasive and, therefore,
reject Proxyconn’s argument that Santos does not perform “searching in
predetermined locations.”
For the foregoing reasons, we conclude that Microsoft has established
by a preponderance of evidence that Santos anticipates claim 23.
d. DRP
(1) Claims 6, 7, and 9
Proxyconn argues that DRP does not anticipate claims 6, 7, and 9
because it fails to describe the following three limitations on the caching
computer recited in claim 6: (i) a “permanent storage memory;” (ii) “means
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for comparison;” and (iii) “means for calculating a digital digest” as recited
in claim 6. Resp. 37–38. Proxyconn argues that DRP also fails to describe
additional limitations on the caching computer that are recited in dependent
claims 7 and 9.5 However, those arguments rely upon Proxyconn’s
contention that DRP fails to disclose a network cache in permanent storage
memory. Resp. 38–39. Microsoft contends that DRP describes the claimed
caching computer as any of its client and server computers, all of which
have “permanent storage memory,” “means for comparison,” and “means for
calculating a digital digest.” MS Reply 8–9. Microsoft also contends that
DRP’s client and server computers meet each of the additional limitations on
the caching computer that are recited in dependent claims 7 and 9.
Proxyconn’s argument rests upon Proxyconn’s interpretation of “two
other computers” as excluding the “caching computer.” We have rejected
Proxyconn’s interpretation as explained in Part II.A.4 above. Proxyconn
does not otherwise dispute Microsoft’s characterization of DRP’s client or
server computers as meeting all the limitations on the “caching computer”
that are recited in claims 6, 7, and 9. Therefore, we determine that Microsoft
has established by a preponderance of evidence that DRP anticipates claims
6, 7, and 9.

5 Claim 7 depends upon claim 6 and further recites “said caching computer
further includes means for calculating a digital digest for data in its network
cache memory.” Ex. 1002, col. 11, ll. 13–15. Claim 9 also depends upon
claim 6 and further recites “said caching computer further includes means
for storing said digital digest in said permanent storage memory.” Id. at
col. 11, ll. 18–20.
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(2) Claims 11, 12, and 14
Microsoft identifies in great detail how DRP’s clients and servers
communicate according to the methods of claims 11, 12, and 14. ’109
Petition, Appendix A 16–22; MS Reply 9–10 (citing DRP. 4:37–5:19, 5:22–
32, 6:40–7:1, 7:20–29, 7:31–35, 7:37–39, 8:11–13, 8:29–31, 9:22–32;
Konchitsky Tr. 91:18–94:7, 98:5–11, 108:11–109:18). Proxyconn argues
that DRP fails to describe the step of “receiving a response signal from said
receiver/computer at said sender/computer, said response signal containing a
positive, partial or negative indication signal for said digital digest, and if a
negative indication signal is received, transmitting said data from said
sender/computer to said receiver/computer” as recited in independent claim
11. Resp. 40. Proxyconn contends that DRP’s statement that the “client can
use the index to automatically download the files that are specified” means
that the client downloads specific files without ever sending a response
signal to the server. Id. Proxyconn also argues that DRP fails to describe
the requirement in claim 14 of “a response signal is sent containing a
separate indication signal for each of said data objects.” Id. at 41.
We reject Proxyconn’s arguments regarding both claims. DRP
describes that the client, after comparing the received digest of files with the
digest for its cached versions, sends a GET request (when none of the
digests for files match), a differential GET request (when some, but not all,
of the digests for files in the cache match), or no request (when all digests
for the files in the cache match). DRP, 5:22–32, 6:44, 7:20–28, 8:11–13.
Dr. Konchitsky confirms the accuracy of Microsoft’s position regarding the
GET and differential GET requests that the client might send to the server.
Konchitsky Tr. 108:11–109:18. The three types of responses that the client
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sends to the server after receiving the index from the server and comparing it
to the local index constitute the claimed “response signal containing a
positive, partial or negative indication signal” of claim 11. These types of
responses also correlate to the “separate indication signal” of claim 14.
Proxyconn proffers no argument independently distinguishing claim 12 from
DRP. Therefore, we conclude that DRP anticipates claims 11, 12, and 14.
2. Obviousness
“Section 103 [of 35 U.S.C.] forbids issuance of a patent when ‘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). To establish obviousness of a claimed invention, all the
claim limitations must be taught or suggested by the prior art. See CFMT,
Inc. v. Yieldup Int’l Corp., 349 F.3d 1333, 1342 (Fed. Cir. 2003); In re
Royka, 490 F.2d 981, 985 (CCPA 1974).
a. Yohe and Perlman
Microsoft contends that the combination of Yohe and Perlman renders
claims 1, 3, 10, and 22–24 obvious under 35 U.S.C. § 103(a). Dr. Long
testified that a skilled artisan would have considered Yohe and Perlman to
be closely related technologies that are natural to combine because both
references address the same problem and use the same algorithm in similar
applications. Ex. 1007, 9:12–10:13. Dr. Long also testified that Perlman
expressly suggests that its technology is suited for use in any type of node in
a network for which synchronization of data is important. Id. at 11:1–7.
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Proxyconn does not address the sufficiency of the combined teachings
of Yohe and Perlman regarding the subject matter of claims 1, 3, 10, and 22–
24. Instead, Proxyconn first argues that Perlman is not a proper reference to
consider in an obviousness analysis because a skilled artisan would not
consider Perlman to be analogous art to the claimed invention. Resp. 28–31.
Dr. Konchitsky testified that the ’717 Patent addresses increasing data access
speed by conserving bandwidth while Perlman uses additional bandwidth to
keep its nodes synchronized. Ex. 2002, 6. Dr. Konchitsky concluded that a
skilled artisan would not consider Perlman to describe a viable way of
increasing data access.
Dr. Long testified that Perlman, Yohe, and the ’717 Patent all address
the same problem: “the desire to reduce redundancy in network data
transmissions where dynamic data previously sent over the network has been
stored by the receiver for possible later reuse.” Ex. 1007, 9:13–15. We find
Dr. Long’s statement of the problem addressed by the ’717 Patent, Perlman,
and Yohe to be persuasive. The ’717 Patent states: “The performance gains
realized by the present invention are derived from the fact that computers in
common wide-area networks tend to repetitively transmit the same data over
the network.” Ex. 1002, col. 6, ll. 17–20. Both Perlman and Yohe describe
reducing the use of bandwidth for data transmission as a way of improving
network performance. Ex. 1007, 9:19–10:4 (citing Ex. 1003, col. 3, ll. 52–
55; Ex. 1005, col. 4, ll. 32–40). Therefore, we reject Proxyconn’s argument
that a skilled artisan would not consider Perlman’s teachings to be pertinent
to the invention.
Proxyconn also argues that it would not have been obvious to
incorporate Yohe’s permanent storage memory into Perlman’s router
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because such memory would serve no function in Perlman’s router. Resp.
31–32. “The test for obviousness is not whether the features of a secondary
reference may be bodily incorporated into the structure of the primary
reference. . . . Rather, the test is what the combined teachings of the
references would have suggested to those of ordinary skill in the art.” In re
Keller, 642 F.2d 413, 425 (CCPA 1981) (citations omitted). Dr. Long
testified at length about the reasons why a skilled artisan would have used
permanent storage memory as taught by Yohe for the cache in Perlman.
Ex. 1007, 12:4–15:9. Proxyconn proffers no persuasive evidence in support
of its position. Therefore, we reject Proxyconn’s argument that a skilled
artisan would not have found it obvious to use permanent storage memory in
the receiver/computer and sender/computer.
For the combination of Yohe and Perlman to render claims 1, 3, 10,
and 22–24 obvious, the combination still must describe or suggest all
limitations of the claims. Therefore, we analyze the teachings and the
differences, if any, between the combination of Yohe and Perlman and the
claims below.
(1) Claims 1, 3, and 10
As discussed in Part II.C.1 above, we determine that Yohe anticipates
claim 10, but that neither Yohe nor Perlman anticipates claims 1 and 3. The
only limitation recited in claims 1 and 3 not described by Yohe is the
“means for comparison of digital digests on data” located in the
receiver/computer. See Part II.C.1.b(1) above. However, Yohe describes
comparator 58 in cache verifying computer 14 that would, if located in the
remote client, meet the recited “means for comparison of digital digests.”
Additionally, Perlman describes performing the comparison of digital
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digests on data in the receiver because Perlman’s receiving router compares
a received digest with a locally generated and stored digest.
Ex. 1003, col. 7, ll. 56–63.
Thus, we must decide whether a skilled artisan would have found it
obvious to incorporate Perlman’s comparing means into Yohe’s remote
client or to move or add Yohe’s comparator 58 from cache verifying
computer 14 into remote client 12. Both Perlman and Yohe describe devices
that compare digital digests on data. Ex. 1003, col. 7, ll. 56–63; Ex. 1005,
col. 6, ll. 22–37, Figures 6 and 7. Yohe suggests that “[i]t is recognized that
other locations for the comparator [58] may exist.” Ex. 1005, col. 13, ll. 32–
34. Proxyconn has not suggested that Yohe’s comparator would not be
capable of performing the recited function of “comparison of digital digests
on data.” Incorporating Perlman’s comparing means into Yohe’s remote
client or moving Yohe’s comparator 58 into the remote client would have
involved nothing more than ordinary skill and would have been using known
devices to perform known functions to yield predictable results. We
conclude that a skilled artisan would have found it obvious to include the
recited “means for comparison of digital digests on data” in a
receiver/computer. For these reasons, we conclude that Microsoft has
established by a preponderance of evidence that the combination of Yohe
and Perlman renders claims 1, 3, and 10 unpatentable as obvious under 35
U.S.C. § 103(a).
(2) Claims 22–24
As explained in Parts II.C.1.a(2) and II.C.1.b(3) above, neither
Perlman nor Yohe describes, “searching” as required by claim 22. We
cannot conclude that a claim would have been obvious when the prior art
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does not describe every element recited in the claim. Claims 23 and 24
depend from claim 22. Therefore, we conclude that Microsoft has not
established by a preponderance of evidence that claims 22–24 are
unpatentable as obvious under 35 U.S.C. § 103(a).
b. Mattis and DRP
For the reasons expressed in Part II.C.1.d above, we determine that
DRP anticipates claims 6, 7, 9, 11, 12, and 14. Because we cancel these
claims based on DRP alone, we determine that Microsoft’s challenge to the
patentability of claims 6, 7, 9, 11, 12, and 14 as being obvious in light of
Mattis combined with DRP is moot and do not address this challenge.
D. Proxyconn’s Motion to Amend
Proxyconn moved to substitute claims 35–416 for challenged claims 1,
3, 6, 10, 11, 22, and 23, respectively, if the Board were to cancel any of
those challenged claims as unpatentable. Mot. Amend 1. Proxyconn also
requests that we enter claims 35–41 “in addition to the original claims.” Id.
Proxyconn may not add a proposed claim while retaining the original claim
for which the proposed claim is substituted. 35 U.S.C. § 316(d)(1)(B) and
37 C.F.R. § 42.121(a)(3). Therefore, to the extent that Proxyconn’s Motion
to Amend requests entry of substitute claims in addition to the original
claims, we deny the Motion.

6 Proxyconn mistakenly refers to substitute claims 35–42 in its Motion to
Amend, but proffers only claims 35–41 as substitutes for claims 1, 3, 6, 10,
11, 22, and 23, respectively. Mot. Amend, Appendix A.
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1. Proxyconn’s Burden of Persuasion Relating to Claims 35–
41
Inter partes review is neither examination nor reexamination of a
patent application. We do not enter proposed substitute claims as a matter of
right. Rather, the patent owner must prove its entitlement to the proposed
claims. Rule 42.20(c) states: “(c) Burden of proof. The moving party has
the burden of proof to establish that it is entitled to the requested relief.” 37
C.F.R. § 42.20(c). We set forth the requirements for demonstrating the
prima facie patentability of substitute claims in Idle Free Sys., Inc. v.
Bergstrom, Inc., IPR2012-00027, Paper 26, as follows:
A patent owner should identify specifically the feature or
features added to each substitute claim, as compared to the
challenged claim it replaces, and come forward with technical
facts and reasoning about those feature(s), including
construction of new claim terms, sufficient to persuade the
Board that the proposed substitute claim is patentable over the
prior art of record, and over prior art not of record but known to
the patent owner. The burden is not on the petitioner to show
unpatentability, but on the patent owner to show patentable
distinction over the prior art of record and also prior art known
to the patent owner. Some representation should be made about
the specific technical disclosure of the closest prior art known
to the patent owner, and not just a conclusory remark that no
prior art known to the patent owner renders obvious the
proposed substitute claims.
A showing of patentable distinction can rely on
declaration testimony of a technical expert about the
significance and usefulness of the feature(s) added by the
proposed substitute claim, from the perspective of one with
ordinary skill in the art, and also on the level of ordinary skill,
in terms of ordinary creativity and the basic skill set. A mere
conclusory statement by counsel, in the motion to amend, to the
effect that one or more added features are not described in any
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prior art, and would not have been suggested or rendered
obvious by prior art, is on its face inadequate.
Idle Free Sys., Inc. v. Bergstrom, Inc., IPR2012-00027, slip op. at 7–8
(PTAB June 11, 2013 (Paper 26)); see also Idle Free Sys., Inc. v. Bergstrom,
Inc., IPR2012-00027, slip op. 33–38 (PTAB January 7, 2014 (Paper 66)).
Proxyconn has not proffered sufficient arguments or evidence to
establish a prima facie case for the patentability of claims 35–41. For
example, Proxyconn has not: (i) construed the newly added claim terms; (ii)
addressed the manner in which the claims are patentable generally over the
art; (iii) identified the closest prior art known to it; (iv) addressed the level of
ordinary skill in the art at the time of the invention; or (v) discussed how
such a skilled artisan would have viewed the newly recited elements in
claims 35–41 in light of what was known in the art. Instead, Proxyconn
attempts to distinguish claims 35–41 only from the prior art for which we
instituted review of corresponding claims 1, 3, 6, 10, 11, 22, and 23. Mot.
Amend 4–15. Consequently, Proxyconn has failed to establish a prima facie
case for the patentability of claims 35–41. Proxyconn’s motion to amend in
connection with claims 35–41 is, therefore, denied on these grounds. We
also find Proxyconn’s motion unavailing for additional reasons raised by
Microsoft as described below.
2. Patentability of Claims 35–41 in light of DRP
a. Claims 35, 36, 38, 40, and 41
Microsoft contends that DRP anticipates claims 35, 36, 38, and 40–41
and supports its contentions with detailed citations to DRP. Microsoft
Corporation’s Opposition to Patent Owner’s Corrected Motion to Amend
under 37 C.F.R. § 42.121 (Paper 48) 1–15 (“MS Amend Opp.”). In its
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Motion to Amend, Proxyconn does not compare claims 35, 36, 38, 40, and
41 to DRP. Mot. Amend 4–13. Proxyconn argues that Microsoft
improperly injects a “new ground of review” into the trial by asserting that
DRP would anticipate claims 35, 36, 38, 40, and 41 because these claims are
amended versions of claims 1, 3, 10, 22, and 23 respectively, for which no
challenge based on DRP has been instituted. Mot. Amend Reply 2–3.
Proxyconn’s argument is unpersuasive. “Petitioners may respond to
new issues arising from proposed substitute claims including evidence
responsive to the amendment. 35 U.S.C. 316(a) and 326(a). This includes
the submission of new expert declarations that are directed to the proposed
substitute claims.” Office Patent Trial Practice Guide, 77 Fed. Reg. 48,756,
48,767 (August 14, 2012).7 Microsoft has provided evidence—i.e., specific
citations to portions of DRP—that responds to new issues introduced by
Proxyconn’s proposed substitute claims. Microsoft is entitled to do so.
Proxyconn provides no evidence to counter Microsoft’s contentions that
DRP anticipates claims 35, 36, 38, 40, and 41. Proxyconn carries the burden
of proof with respect to the patentability of its proposed claims. 37 C.F.R.
§ 42.20(c). Because the only evidence of record supports Microsoft’s
position, we conclude that Proxyconn has failed to establish by a
preponderance of evidence that claims 35, 36, 38, 40, and 41 are patentable

7 Proxyconn’s Motion to Amend was filed after publication of our decision
in Idle Free Sys., Inc. v. Bergstrom, Inc., IPR2012-00027, Paper 26,
discussed above, which set forth the requirements for meeting the burden of
proof on a motion to amend. We also reminded Proxyconn at the oral
hearing of its duty to distinguish the proposed claims from all prior art of
which it is aware, including DRP. Tr. 64:3–13.
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over DRP. Therefore, we deny the Motion to Amend as it relates to claims
35, 36, 38, 40, and 41.
b. Claim 37
Claim 37, which is substituted for claim 6, is reproduced below with
additions indicated by underlining.
37. A system for data access in a packet-switched
network, comprising:
a gateway including an operating unit, a memory and a
processor connected to said packet-switched network in such a
way that network packets sent between at least two other
computers pass through it;
a caching computer connected to said gateway through a
fast local network, wherein said caching computer includes an
operating unit, a first memory, a permanent storage memory
and a processor; said caching computer further including a
network cache memory in its permanent storage memory,
means for calculating a digital digest on data and means for
comparison between a digital digest on data in its network
cache memory and a digital digest received from said packet-
switched network through said gateway, wherein said data
includes a plurality of octet ranges in a file or files.
Mot. Amend, App. A, 1–2.
We have determined that DRP anticipates claim 6. See Part
II.C.1.d(1) above. Proxyconn’s entire argument for distinguishing claim 37
from DRP is: “Substitute claim 37 requires structure to operate a data
including a plurality of octet ranges in a file or files. DRP discloses content
identifier based on information objects . . . . Lacking this additional
element, DRP . . . fail[s] to anticipate and/or render obvious Substitute
Claim 37.” Mot. Amend 8–9. Proxyconn fails to cite any support for its
characterization of DRP. Microsoft responds: “The data processed in DRP
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includes plural files and thus includes a plurality of ranges of octets in plural
files. . . . The ‘data that is distributed . . . can consist of any kind of code or
content.’” MS Amend Opp. 6 (citing DRP, 2:31–32, 2:44–3:2, 3:14–16,
3:28–31) (internal citation omitted). Because we agree with Microsoft, we
determine that Proxyconn has failed to establish by a preponderance of
evidence that claim 37 is patentable over DRP.
c. Claim 39
Claim 39, which is substituted for claim 11, is reproduced below with
additions indicated by underlining and deletions indicated by double square
bracketing.
39. A method performed by a sender/computer in a
packet-switched network for increasing data access, said
sender/computer including an operating unit, a first memory, a
permanent storage memory and a processor and said
sender/computer being operative to transmit data to a
receiver/computer, the method comprising the steps of:
creating a digital digest on data; [[and]]
receiving a request for said data from the
receiver/computer;
in response to the request for data, transmitting said [[a]]
digital digest of said data from said sender/computer to said
receiver/computer;
receiving a response signal from said receiver/computer
at said sender/computer, said response signal containing a
positive, partial or negative indication signal for said digital
digest, and
if a negative indication signal is received, transmitting
said data from said sender/computer to said receiver/computer.
Mot. Amend, App., A 2–3.
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Proxyconn contends, without citing any portion of DRP in support,8
that DRP fails to describe “the step of receiving a request for data, and in
response to the request for data, transmitting a digital digest for the data.”
Mot. Amend 10. In response, Microsoft contends that DRP describes this
missing step being performed by the server responding to a GET request
from the client for an index file with the current version of the index. MS
Amend Opp. 10–11 (citing DRP, 5:22–32, 6:43–7:1, 7:20–31, 7:37–38, 8:8–
13, 9:22–32). We determine that on the evidence before us, Proxyconn has
failed to establish by a preponderance of evidence that claim 39 is patentable
over DRP.
3. Alleged Broadening of Scope in Claims 36, 38, 40, and 41
During inter partes review, a patent owner may not amend a
challenged claim in a manner that enlarges the scope of that claim. 35
U.S.C. § 316(d)(3); 37 C.F.R. § 42.121(a)(2)(ii). Proxyconn states without
further discussion that “the amendments herein do not seek to enlarge the
scope of the claims of the ’717 Patent.” Mot. Amend 1. Microsoft argues
that Proxyconn’s proposed claims 36, 38, 40, and 41 impermissibly enlarge
the scope of challenged claims 3, 10, 22, and 23 respectively. MS Amend
Opp. 4, 7. We address each of these claims in turn below.

8 Proxyconn cites section II.F (sic, II.G) of Proxyconn’s Patent Owner
Response. Mot. Amend 10. However, this section of the Response cites
only ¶¶ 52–61 of Dr. Konchitsky’s Declaration. Resp. 36–41. None of
those paragraphs cites any portion of DRP to support Dr. Konchitsky’s
testimony. See Ex. 2002, Konchitsky Decl. ¶¶ 52–61.
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a. Claim 36
Claim 36, which is substituted for claim 3, is reproduced below with
additions indicated by underlining and deletions indicated using
strikethrough or double square bracketing.
36. A system for data access in a packet-switched
network, comprising[[:]] a sender/computer including an
operating unit, a first memory, a permanent storage memory
and a processor; and a remote receiver/computer including an
operating unit, a first memory, a permanent storage memory
and a processor[[,]]; said sender/computer and said
receiver/computer communicating through said network;
configured to communicate with one another through said
network; said sender/computer further includesing means for
creating digital digests on data[[;]] stored in said permanent
storage memory, and said receiver/computer further including a
network cache memory and, means for creating digital digests
on data in said network cache memory[[;]], and said
receiver/computer including means for comparison comparing
between digital digests created by the sender/computer and
receiver/computer; wherein said receiver/computer further
includes means for storing said created at least one of the digital
digests created by the sender/computer in its first or permanent
storage memory; wherein the data includes at least a range of
octets in a file.
See Mot. Amend, App. A, 1.
Microsoft argues that Proxyconn enlarges claim 36 in two ways.
First, the claim is allegedly enlarged by changing the requirement that the
sender/computer and receiver/computer are “communicating through said
network” to two computers that are “configured to communicate with one
another through said network.” MS Amend Opp. 4. We agree that claim 36
no longer requires that the sender and receiver computers are
communicating through the network, which would necessarily also require
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that the computers be “configured” to so communicate. Claim 36 more
broadly covers sender and receiver computers that are configured to
communicate, but are not necessarily communicating. Doing so
impermissibly enlarges the scope of claim 3. Therefore, we deny
Proxyconn’s motion to amend regarding claim 36, and need not reach
Microsoft’s second argument.
b. Claim 38
Claim 38, which is substituted for claim 10, is reproduced below with
additions indicated by underlining and deletions indicated using
strikethrough or double square bracketing.
38. A system for data access in a packet-switched
network, comprising:
a sender/computer including an operating unit, a first
memory, a permanent storage memory and a processor and a
remote receiver/computer including an operating unit, a first
memory, a permanent storage memory and a processor, said
sender/computer and said receiver/computer communicating
through a network;
said sender/computer further including means for
creating digital digests on data, and
said receiver/computer further including a network cache
memory, means for storing [[a]] at least one of said digital
digest received from said network in its permanent storage
memory, and said receiver/computer configured to search for a
digital digest received from the sender/computer, in response to
receiving the digital digest, means for comparison between
digital digests; wherein said data includes at least a range of
octets in a file.
Mot. Amend, App. A, 2.
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Microsoft argues that “said receiver/computer configured to search for
a digital digest received from the sender/computer, in response to receiving
the digital digest” covers subject matter not covered by the
receiver/computer’s “means for comparison between digital digests” recited
in claim 10. MS Amend Opp. 6–7. Microsoft contends, “[f]or example, the
receiver might check for a given digest by comparing hashes (or other
identifiers) of digital digests not the digital digests themselves.” Id. at 7.
We agree. Claim 38 covers a receiver/computer that can search for a digital
digest in ways other than comparing the digital digests themselves.
Therefore, we deny Proxyconn’s motion to amend regarding claim 38.
c. Claims 40 and 41
Claim 40, which is substituted for claim 22, is reproduced below with
additions indicated by underlining and deletions indicated using
strikethrough or double square bracketing.
40. A method for increased data access performed by a
receiver/computer in a packet-switched network, said
receiver/computer including an operating unit, a first memory, a
permanent storage memory, a processor and a network cache
memory, said method comprising the steps of:
sending a request for data;
receiving a message containing a digital digest for the
requested data from said network;
searching for each received digital digest data with the
same digital digest in said network cache memory,
if data having the same digital digest as the digital digest
received is not uncovered, forming a negative indication signal
and transmitting the negative indication signal [[it]] back
through said network; and
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creating a digital digest for data received from the
sender/computer and stored in said network cache memory.
Mot. Amend, Appendix A 3.
Claim 41, which is substituted for claim 23, is reproduced below with
additions indicated by underlining and deletions indicated using
strikethrough.
41. The method as claimed in claim 22, claim 40,
wherein searching in said network cache memory includes
further comprising searching in predetermined locations in said
permanent storage memory for data with a digital digest
substantially identical to the searched one of the digital digests
received from said network.
Id.
Microsoft argues that the third and fourth changes to claim 22
reflected in proposed claim 40 impermissibly enlarge the scope of claim 22.
Microsoft contends that “[c]laim 40 newly covers methods that look only for
matching digests but not for data having those digests. Claim 22 does not
cover such a method.” MS Amend Opp. 11. Proxyconn responds that
“searching specifically for ‘each received digital digest,’ . . . is narrower
than merely searching generally for data by the digital digest.” Mot. Amend
Reply 5. Proxyconn’s argument mischaracterizes claim 22 as requiring
“searching generally for data by the digital digest.” Claim 22 recites:
“searching for data with the same digital digest” not “by the same digest.”
The question presented by the parties’ arguments is whether it is
possible to search for each received digital digest without searching for data
having the same digital digest. Microsoft does not identify an example of
how one might search for data with the same digest without using the digest.
However, Proxyconn does not provide evidence that it is not possible to
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search for each received digest without searching for data having the same
digest. Without such evidence, we can only evaluate the scope of the claim
based on the plain meaning of the terms. On that basis, we conclude that it
would be possible to search for each received digital digest without
searching for data having the same digital digest. Therefore, it is possible to
practice the method recited in claim 40 without practicing the method recited
in claim 22. For this reason, we conclude that claim 40 is impermissibly
broader than claim 22. The same flaw exists in claim 41, which depends
from claim 40. Therefore, we deny Proxyconn’s Motion to Amend as it
relates to claims 40 and 41.
III. CONCLUSION
Microsoft has established by a preponderance of evidence that claims
1, 3, 6, 7, 9, 10, 11, 12, 14, 22, and 23 are unpatentable as anticipated and
claims 1, 3, and 10 are unpatentable as being directed to obvious subject
matter. Microsoft has not established by a preponderance of evidence that
claim 24 is unpatentable.
IV. ORDER
It is ORDERED that:
Claims 1, 3, 6, 7, 9–12, 14, 22, and 23 are CANCELED; and
Proxyconn’s Motion to Amend Claims is DENIED.
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PATENT OWNER:
Matthew L. Cutler
Bryan K. Wheelock
Douglas A. Robinson
HARNESS, DICKEY & PIERCE, PLC
mcutler@hdp.com
bwheelock@hdp.com
drobinson@hdp.com
PETITIONER:
John D. Vandenberg
Stephen J. Joncus
KLARQUIST SPARKMAN LLP
john.vandenberg@klarquist.com
stephen.joncus@klarquist.com