NOTE: This disposition is nonprecedential.

United States Court of Appeals 

for the Federal Circuit ______________________

MICROSOFT CORPORATION, INTERNATIONAL 

BUSINESS MACHINES CORPORATION,

Appellants

v.

PARALLEL NETWORKS LICENSING, LLC,

Appellee

______________________

2016-2515, 2016-2517, 2016-2518, 2016-2519, 2016-2642, 

2016-2644, 2016-2645, 2016-2646

______________________

Appeals from the United States Patent and Trademark Office, Patent Trial and Appeal Board in Nos. 

IPR2015-00483, IPR2015-00484, IPR2015-00485, 

IPR2015-00486, IPR2015-01729, IPR2015-01731, 

IPR2015-01732, IPR2015-01734.

______________________

Decided: December 1, 2017

______________________

CONSTANTINE L. TRELA, JR., Sidley Austin LLP, Chicago, IL, argued for appellants. Appellant Microsoft 

Corporation also represented by RICHARD ALAN 

CEDEROTH; MICHAEL D. HATCHER, Dallas, TX; JOSHUA 

JOHN FOUGERE, DANIEL HAY, JOSEPH A. MICALLEF, Washington, DC.
2 MICROSOFT CORP. v. PARALLEL NETWORKS LICENSING

JOHN M. DESMARAIS, Desmarais LLP, New York, NY, 

for appellant International Business Machines Corporation. Also represented by JON TODD HOHENTHANER,

KEVIN KENT MCNISH, JEFFREY SCOTT SEDDON, II.

CHRISTOPHER THOR BOVENKAMP, McKool Smith, PC, 

Dallas, TX, argued for appellee. Also represented by 

DOUGLAS AARON CAWLEY; KEVIN P. HESS, DUSTIN MARK 

HOWELL, Austin, TX.

______________________

Before DYK, SCHALL, and TARANTO, Circuit Judges.

TARANTO, Circuit Judge.

Parallel Networks Licensing, LLC owns U.S. Patents 

5,894,554 and 6,415,335 (the Parallel Patents), which 

describe and claim systems for managing the handling of 

requests for World Wide Web pages having dynamic 

(changing) content. ’554 patent, col. 2, lines 15–19, lines 

20–32; ’335 patent, col. 2, lines 15–19, lines 20–32. Parallel sued Microsoft Corp. and International Business 

Machines (IBM) for infringement. Microsoft and IBM

subsequently filed petitions with the Patent and Trademark Office seeking inter partes reviews of all claims of 

the Parallel Patents under 35 U.S.C. §§ 311–319. The 

Patent Trial and Appeal Board, acting as the delegate of 

the PTO’s Director under 37 C.F.R. § 42.4(a), instituted 

reviews of all challenged claims on anticipation and 

obviousness grounds, and it consolidated the proceedings 

into two, one for each of the Parallel Patents, with Microsoft and IBM both involved as petitioners. After 

conducting the reviews, the Board concluded that the 

petitioners failed to demonstrate anticipation or obviousness.

Microsoft and IBM appeal the Board’s decisions, arguing that the Board erred in construing the claim term 
MICROSOFT CORP. v. PARALLEL NETWORKS LICENSING 3

“request” and in rejecting the arguments for unpatentability. We affirm the Board’s claim construction, but we 

vacate in part the determination regarding anticipation, 

vacate the Board’s determination regarding obviousness, 

and remand for further proceedings.

I

A

The Parallel Patents claim priority to an application 

filed in 1996. By the mid-1990s, the number of Web page 

requests had grown large. See ’554 patent, col. 1, lines 

39–41, col. 4, lines 33–39.1 If many requests came to a 

single-processor server simultaneously, the server could 

be overwhelmed, and the efficiency of fulfilling requests 

could suffer. Id., col. 4, lines 38–51. The Parallel Patents

address the problem of processing numerous dynamic 

Web page generation requests using a partitioned architecture. Id. at col. 4, lines 51–53. The partitioned architecture includes a Web server, interceptor, dispatcher, 

and multiple page servers. Id., fig. 4. The basic method 

recited in the challenged claims is as follows: (1) a Web 

page request is sent to a Web server; (2) the request is 

intercepted; (3) an appropriate page server to process the 

request is determined; and (4) the request is routed to the 

appropriate page server. See id., col. 4, lines 54–60, col. 5, 

lines 38–43 & fig. 4.

The page server is determined based on dynamic system resource information, e.g., the data sources each page

server can access and the number of requests each page 

server is processing. Id., col. 5, line 49 through col. 6, line 

19. By routing a request to a page server, the Web server 

 

1 The ’335 patent issued from a divisional application that claims priority to the ’554 patent’s underlying 

application; the specifications are nearly identical. Thus, 

we omit duplicate citations to the ’335 patent.
4 MICROSOFT CORP. v. PARALLEL NETWORKS LICENSING

is free to “concurrently process other Web client requests.” 

Id., col. 6, lines 20–25. The partitioned architecture 

allows the page servers and the Web server “to simultaneously process different requests, thus increasing the 

efficiency of the Web site.” Id., col. 6, lines 24–28.

In July 2012, the PTO issued ex parte reexamination 

certificates for both of the Parallel Patents.2 All of the 

original claims in the ’554 patent were canceled and new 

claims 12–49 were added. J.A. 67. Similarly, all of the 

original claims in the ’335 patent were canceled and new 

claims 30–85 were added. J.A. 88. For present purposes, 

claim 12 of the ’554 patent is representative. It reads: 

A computer-implemented method for managing a 

dynamic Web page generation request to a Web 

server, said computer-implemented method 

comprising the steps of:

routing said request from said Web server to a selected page server, said selected page server receiving said request and releasing said Web 

server to process other requests, wherein said 

routing step further includes the steps of intercepting said request at said Web server, routing 

said request from said Web server to a dispatcher, and dispatching, by said dispatcher, said request to said selected page server;

processing said request, said processing being performed by said selected page server while said 

Web server concurrently processes said other 

requests; and

 

2 The ’335 patent’s ex parte reexamination certificate issued on July 17, 2012, and the ’554 patent’s ex 

parte reexamination certificate issued on July 24, 2012. 

Corresponding certificates of correction issued on those 

same days. J.A. 66–74, J.A. 87–97.
MICROSOFT CORP. v. PARALLEL NETWORKS LICENSING 5

dynamically generating a Web page by said selected page server in response to said request, 

said Web page including data dynamically retrieved from one or more data sources; and

wherein dispatching includes:

examining said request to make a selection of 

which page server should process said request 

from among a plurality of page servers that 

can each generate said Web page requested by 

said request;

selecting one of said plurality of page servers to 

dynamically generate said Web page;

wherein said selection is based on examining 

dynamic information regarding a load associated with each of said plurality of page servers; and

sending said request to said selected page server 

based on said examination.

J.A. 69 (certificate of correction). The dispatcher may 

reside on the same machine as the Web server or on a 

different machine. ’554 patent, col. 5, lines 8–28. 

B

In December 2014, Microsoft filed four petitions for 

inter partes reviews, together challenging all claims of the 

Parallel Patents under 35 U.S.C. §§ 102 and 103.3 As to 

the ’554 patent, the Board instituted reviews of claims 

12–19, 32, 34, 46 and 48 in IPR2015-00483 (IPR-483) and 

 

3 The Parallel Patents claim priority to a 1996 application and are governed by the versions of §§ 102 and 

103 that were in effect before amendment by the LeahySmith America Invents Act, Pub. L. No. 112-29, § 3(n)(1), 

125 Stat. 284, 293 (2011).
6 MICROSOFT CORP. v. PARALLEL NETWORKS LICENSING

claims 12, 20–31, 33, 35–45, 47 and 49 in IPR2015-00484. 

The Board consolidated those reviews into IPR-483, which 

involves claims 12–49 of the ’554 patent. As to the ’335 

patent, the Board instituted reviews of claims 30–40, 43–

53, and 56–85 in IPR2015-00485 (IPR-485) and claims 32, 

33, 35–42, 45, 46, 48–55, 65, 69, 80, and 84 in IPR2015-

00486. The Board consolidated those reviews in IPR-485, 

which involves claims 30–85 of the ’335 patent. In August 

2015, IBM filed four petitions for inter partes reviews, all 

substantially similar to the Microsoft petitions. The 

Board instituted reviews on the IBM petitions and joined 

IBM as a petitioner to IPR-483 and IPR-485. 

In its August 2016 Final Written Decision for IPR483, the Board concluded that Microsoft and IBM (hereafter collectively “Microsoft”) failed to demonstrate the 

unpatentability of claims 12–49 of the ’554 patent over 

the cited prior art. Microsoft Corp. v. Parallel Networks 

Licensing, LLC, IPR2015-00483, 2016 WL 8944632, at *11 

(P.T.A.B. Aug. 11, 2016) (IPR-483 Final Decision). The 

Board reached the same conclusion in IPR-485 for claims 

30–85 of the ’335 patent. Microsoft Corp. v. Parallel 

Networks Licensing, LLC, IPR2015-00485, 2016 WL 

8999702, at *10 (P.T.A.B. Aug. 11, 2016) (IPR-485 Final 

Decision).4

Microsoft appeals the Board’s Final Written Decisions 

under 35 U.S.C. §§ 141(c) and 319. We have jurisdiction 

under 28 U.S.C. § 1295(a)(4)(A).

II

The main prior-art reference considered by the Board 

for both anticipation and obviousness is a 1995 publica-

 

4 The Board’s Final Written Decisions in IPR-483 

and IPR-485 are substantially similar. We will refer only 

to the decision in IPR-483, but our conclusions apply to 

both.
MICROSOFT CORP. v. PARALLEL NETWORKS LICENSING 7

tion by Daniel Andresen and others: SWEB: Towards a 

Scalable World Wide Web Server on Multicomputers, 

Dept. of Computer Sci. Tech. Report TRCS95-17, U.C. 

Santa Barbara (Sept. 1995) (SWEB). The publication 

discloses a “scalable Web server” implemented on a “cluster of workstations and parallel machines” for the efficient 

processing of relatively large numbers of simultaneous 

Web page requests. Id. at 1–2. The system includes a 

number of distributed Web servers that can either (a) 

themselves act as a page server when appropriate or (b), 

based on dynamic system load information, identify 

another Web server that can more efficiently get the 

client the desired information and take steps to have that 

server do so. Id. SWEB states that its preferred process 

for the latter is “URL redirection,” which refers to the 

Uniform Resource Locator tool for finding Web resources. 

Id. at 10. Figure 6 in SWEB, reproduced below, illustrates that process. Id. at 11.

The Web client (C) sends a Website host name, determined from a URL, to a domain name server (DNS),

asking for an Internet Protocol (IP) address for a Web 

server (S?) hosting the site. Id. at 5. In the figure, the 

initial server to which the DNS directs the client is server 

S0. That server, like others in the system, contains a 
8 MICROSOFT CORP. v. PARALLEL NETWORKS LICENSING

scheduler (dispatcher) that communicates with all other 

Web servers to exchange system load information. Id. at 

9. When the client sends request r to server S0, the 

scheduler determines whether S0 or some other server 

should supply the client the desired information. Id. 

If, at the time, server S1 is preferable to S0 as a 

source for the client to get the desired information, “URL 

Redirection” is used to bring about a connection between 

the client and S1. Id. at 10. “[W]hen client C sends a 

request [r] to server S0, S0 returns a rewritten URL r'

and a response code indicating the information is located 

at r'. C then follows r' to retrieve the resulting file f.” Id. 

The client computer can take the needed steps without a 

new action by, or even the knowledge of, the human user 

of client C: “Most Net browsers and clients automatically

query the new location, so redirection is virtually transparent to the user.” Id.

This URL redirection process, while preferred by 

SWEB, is not the only process described in SWEB for 

changing the server that will actually supply the clientdesired information. Before describing URL redirection, 

SWEB states that, where a server other than the initially 

contacted one would be better for serving the client at the 

time, “[t]he best situation would be to modify the UNIX 

sockets package” so that the initially contacted server 

sends the request directly to the desired Web server. Id.

at 10. SWEB explains, however, that such modification 

“is difficult since it requires a substantial modification of 

the UNIX operating system kernel.” Id. It then explains 

the advantages of URL redirection and also the disadvantages, which it indicates are small. Id. at 10–11.

The primary advantages of URL redirection, SWEB 

states, are simplicity and universal compatibility. Id. at 

10. “The primary disadvantage of URL redirection in 

practice is the added overhead of an additional connect/pass request/parse/respond cycle after the redirection 
MICROSOFT CORP. v. PARALLEL NETWORKS LICENSING 9

occurs.” Id. at 11. SWEB evaluates the magnitude of the 

disadvantage. It sets forth a mathematical model based 

on “a very short reply going back to the client browser, 

who then automatically issues another request to the new 

server address.” Id. at 14. It reports experimental results

showing added overhead of URL redirection on the order 

of a few milliseconds in an overall process that took 

multiple seconds to complete. Id. at 21. SWEB characterizes this added overhead as “insignificant.” Id. at 23.

III

A

Microsoft first argues that the Board, when evaluating anticipation and obviousness, erroneously modified its 

otherwise-proper claim construction. The only claim term 

at issue on appeal is “request” in the required “dynamic 

Web page generation request.” The Board expressly 

adopted the construction of “request” that the parties 

agreed on during the pending district court litigation: “a 

message that asks for a Web page.” IPR-483 Final Decision, 2016 WL 8944632, at *4.

When conducting its analysis of the alleged anticipation by SWEB, the Board explained that the claims of the 

Parallel Patents “are directed to the routing and processing of a single request.” Id. at *5. That conclusion is 

not meaningfully in dispute here. And in any event, we 

see no error in it.

What Microsoft argues is that, in its anticipation 

analysis of whether SWEB teaches the claim-required 

steps involving a single request, the Board changed the 

agreed-to simple construction of “request.” Microsoft 

contends that the Board imposed requirements on what 

can be a “request” based on what Microsoft describes as

(1) the particular route the request travels; (2) the particular URL or destination specified; and (3) who or what 

the request contacts along its route. But the Board did 
10 MICROSOFT CORP. v. PARALLEL NETWORKS LICENSING

none of those things. Instead, it determined that, under 

the agreed-on construction, each time the client computer 

sends a message asking for a Web page, it has made a 

new request. IPR-483 Final Decision, 2016 WL 8944632, 

at *6. The Board stated “that it is the act of asking—an 

action taken by the client computer—that defines a 

request.” Id. (emphasis omitted). Contrary to Microsoft’s 

contention, that conclusion does not turn on the route 

taken, destination, or intermediate contacts.

Microsoft’s core complaint seems to be that the Board 

should have focused on what the client is asking for, not 

each individual act of asking, and with that focus should 

have treated even multiple acts of asking as a single 

“request” as long as the content is the same. We have two 

difficulties with this position.

First, at best (for Microsoft’s purposes), there is ambiguity in the agreed-on construction’s term “message”—

whether it refers to substantive communicative content or 

to a discrete act of utterance to convey communicative 

content. But if there is such ambiguity even in the present computer context, it is apparent on the face of the 

term. Yet Microsoft agreed to the term “message” as the 

defining construction in district court, leaving it to the 

fact finder to apply it. And in the present proceedings, 

Microsoft never presented to the Board a request for 

further claim construction. 

Second, we agree with the Board as to the best construction in the context of this patent. This patent concerns computers sending out communications that other 

machines must process, with both the sending and the 

processing requiring expenditure of precious time and 

scarce resources. In this context, the more natural understanding of “request,” as of “message,” is one denoting 

each discrete act of communicating, not one that equates 
MICROSOFT CORP. v. PARALLEL NETWORKS LICENSING 11

discrete utterances when they convey the same content. 

IPR-483 Final Decision, 2016 WL 8944632, at *6–8.5

Accordingly, we reject Microsoft’s assertion that the 

Board committed a claim-construction error.

B

“[T]he dispositive question regarding anticipation is 

whether one skilled in the art would reasonably understand or infer from the prior art reference’s teaching that 

every claim element was disclosed in that single reference.” Dayco Prods., Inc. v. Total Containment, Inc., 329 

F.3d 1358, 1368 (Fed. Cir. 2003) (internal quotation 

marks, alterations, and citation omitted). Anticipation is 

a question of fact, subject to review for substantial evidence. In re Rambus, 753 F.3d 1253, 1256 (Fed. Cir. 

2014).

Microsoft challenged the Parallel Patents as anticipated by two separate methods disclosed in SWEB: (1) 

URL redirection; and (2) modifying the UNIX sockets 

package. We affirm the Board’s finding that SWEB’s 

URL redirection method does not anticipate the claims of 

the Parallel Patents. But the Board failed to address the 

allegation of anticipation by the UNIX sockets modification method. We therefore vacate the Board’s rejection of 

anticipation in part and remand for the Board to consider 

that ground of anticipation in the first instance.

 

5 Because the Parallel Patents expired on April 23, 

2016, before the Board issued its Final Written Decisions, 

the Board properly applied judicial claim-construction 

principles to identify the best construction, rather than 

seeking to identify the broadest reasonable construction. 

See In re Rambus Inc., 694 F.3d 42, 46 (Fed. Cir. 2012)

(inter partes reexamination); Black & Decker, Inc. v. 

Positec USA, Inc., 646 F. App’x 1019, 1024 (Fed. Cir. 

2016) (inter partes review). 
12 MICROSOFT CORP. v. PARALLEL NETWORKS LICENSING

1

Substantial evidence supports the Board’s finding 

that the Web client in the URL redirection disclosure in

SWEB makes two separate requests as that term is used 

in the Parallel Patents. One is made when the initial 

request (r) is sent to the Web server selected by the DNS 

server. Another is made when the request (r') is sent to 

the second Web server identified by the scheduler. IPR483 Final Decision, 2016 WL 8944632, at *8.

Putting aside Microsoft’s claim-construction argument, which we have already rejected, Microsoft makes 

only one response. It accepts the Board’s focus on the 

redirection from one server to another. But it points out 

that the client computer’s human user makes only one 

communication—gives the client computer an instruction 

only once—in the SWEB URL redirection method in that 

circumstance. Microsoft’s Opening Br. 44–45; Microsoft’s

Reply Br. 13. But that is irrelevant under the Parallel 

Patents. The patents refer interchangeably (for these 

purposes) to a request, Web client request, Web browser 

request, and URL request. And, more generally, the 

patents make clear that the requesting entity is the user’s 

computer, i.e., the Web client, not the client’s human user. 

’554 patent, col. 4, line 55 (“Web client 200 issues a URL 

request”), col. 6, lines 29–30 (“Web page is . . . transmitted 

back to requesting Web client 200”).

We find no error in the Board’s determination that 

SWEB’s URL redirection method fails to anticipate the

challenged claims of the Parallel Patents.

2

Microsoft challenges the Board’s rejection of anticipation by SWEB on a separate ground. It observes, correctly, that the Board failed to address Microsoft’s argument 

for anticipation based on SWEB’s disclosure—as an 

alternative to URL redirection—of modifying the UNIX 
MICROSOFT CORP. v. PARALLEL NETWORKS LICENSING 13

sockets package of a server that has received a request so 

that the server forwards the request to a second server 

without, as in URL redirection, involving the client in 

initiating contact with the second server. Such a process 

is a form of what Microsoft’s expert (and the Board) called

“request forwarding” as a name for what the Parallel 

Patents require. See IPR-483 Final Decision, 2016 WL 

8944632, at *9 (quoting J.A. 11449). We agree with 

Microsoft that the Board erred in not addressing this 

argument.

Parallel could not show that the Board actually did 

address this separate basis of alleged anticipation. It 

argues, however, that Microsoft waived this ground of 

anticipation. We cannot so find. Microsoft stated in its 

petitions that SWEB discloses two methods for routing 

requests: URL redirection and UNIX socket modification. 

J.A. 228. Microsoft also clearly argued UNIX socket 

modification as an alternative ground for anticipation of 

the Parallel Patents’ routing limitation. J.A. 231. The 

Board did not find that those clear statements were 

insufficient to entitle Microsoft to a decision on the issue, 

and Parallel has not identified a regulatory or comparable 

requirement for preservation that Microsoft failed to 

meet. We see no basis for Parallel’s argument for finding 

a complete waiver of the issue.

We vacate the rejection of anticipation in part and 

remand for the Board to consider the issue of anticipation 

by SWEB’s disclosure of modifying the UNIX sockets 

package. The Board may consider whether Microsoft 

committed a waiver and, if so, the scope of the waiver. If 

the Board finds no waiver, it should consider whether 

Microsoft has met the required elements of anticipation—

“disclosure of all elements of [the] claimed invention 

arranged as in the claim.” Connell v. Sears, Roebuck & 

Co., 722 F.2d 1542, 1548 (Fed. Cir. 1983). And, if necessary, the Board should address Parallel’s contention that 

this disclosure in SWEB is not enabled—applying our law 
14 MICROSOFT CORP. v. PARALLEL NETWORKS LICENSING

that generally accords a presumption of enablement to 

printed-publication and patent prior art. In re Antor 

Media Corp., 689 F.3d 1282, 1289, 1292 (Fed. Cir. 2012) 

(printed publications); Amgen Inc. v. Hoechst Marion 

Roussel, Inc., 314 F.3d 1313, 1355 (Fed. Cir. 2003) (patents).

C

Microsoft challenged the claims of the Parallel Patents as unpatentable for obviousness over SWEB (and 

other prior art) even if SWEB did not anticipate the 

“request forwarding” required by the claims. In rejecting 

the obviousness challenge, the Board relied on its determination that Microsoft and its expert had “not articulated a sufficient reason why a person of ordinary skill in the 

art would have modified SWEB to include request forwarding.” IPR-483 Final Decision, 2016 WL 8944632, at 

*9–10. Microsoft argues on appeal that the Board failed 

to give proper effect to the testimony of its expert under 

the legal standards for obviousness. We agree to this 

extent: the Board provided insufficient explanation to 

justify rejecting the challenge. We vacate the rejection of 

the obviousness challenge and remand for further proceedings on that challenge. See, e.g., In re Nuvasive, Inc., 

842 F.3d 1376, 1383 (Fed. Cir. 2016); Synopsys, Inc. v. 

Mentor Graphics Corp., 814 F.3d 1309, 1322 (Fed. Cir. 

2016), overruled on other grounds by Aqua Prod., Inc. v. 

Matal, 872 F.3d 1290 (Fed. Cir. 2017); In re Sang Su Lee, 

277 F.3d 1338, 1346 (Fed. Cir. 2002).

An obviousness challenger “must demonstrate . . . 

that a skilled artisan would have had reason to combine 

[or modify] the teaching of the prior art references to 

achieve the claimed invention, and that the skilled artisan would have had a reasonable expectation of success 

from doing so.” Redline Detection, LLC v. Star Envirotech, Inc., 811 F.3d 435, 449 (Fed. Cir. 2015) (quoting PAR 

Pharm., Inc. v. TWI Pharm., Inc., 773 F.3d 1186, 1193 
MICROSOFT CORP. v. PARALLEL NETWORKS LICENSING 15

(Fed. Cir. 2014)). A reason “to modify a reference can 

come from the knowledge of those skilled in the art, from 

the prior art reference itself, or from the nature of the 

problem to be solved.” SIBIA Neurosciences, Inc. v. Cadus 

Pharm. Corp., 225 F.3d 1349, 1356 (Fed. Cir. 2000).

Those standards can and must be understood to follow 

the Supreme Court’s various formulations in KSR Int’l 

Co. v. Teleflex, Inc., 550 U.S. 398 (2007). The KSR formulations include those referring to the “combination of 

familiar elements according to known methods” that “does 

no more than yield predictable results,” id. at 416; “a 

structure already known in the prior art that is altered by 

the mere substitution of one element for another known in 

the field,” requiring more than “a predictable result” for 

patentability, id.; “‘simply arrang[ing] old elements with 

each performing the same function it had been known to 

perform,’ and yield[ing] no more than one would expect 

from such an arrangement,” id. at 417; “a technique [that] 

has been used to improve one device,” where “a person of 

ordinary skill in the art would recognize that it would 

improve similar devices in the same way” and that application is not beyond the ordinary skilled artisan’s skill, 

id.; “the simple substitution of one known element for 

another or the mere application of a known technique to a 

piece of prior art ready for the improvement,” id.; circumstances in which “there is a design need or market pressure to solve a problem and there are a finite number of 

identified, predictable solutions” and “the known options 

[are] within [an ordinary skilled artisan’s] technical 

grasp” and pursuing those options “leads to the anticipated success,” in which case the options are “obvious to try” 

and “might” be obvious, id. at 421. That enumeration is 

not exhaustive, and we are not identifying what aspects of 

KSR are ultimately important in this case.

Microsoft’s expert, Dr. Mitzenmacher, stated in his initial declaration:
16 MICROSOFT CORP. v. PARALLEL NETWORKS LICENSING

214. To the extent Patent Owner may argue 

that SWEB 95 does not disclose “routing said request from said Web server to a selected page server” considering either disclosed method of sending 

requests to other servers, it would have been obvious to include that functionality in the scheme of 

SWEB 95. It was known in the prior art to route 

requests from one machine to another via request

forwarding based upon a determination of which 

server should be used to process such a request. 

See, e.g., Berson, Client/Server Architecture (2d. 

ed. 1996) (published by April 11, 1996 per U.S. 

Copyright Office) (“Berson”) (Ex. 1036) at 207-208 

[J.A. 13311–12] (“Client/server interactions are 

defined as those in which a client initiates the interaction and requests a particular service from 

its ‘home’ server. This server reacts to the client’s 

request by either performing the desired service 

or routing the request to another server for fulfillment of the request; irrespective of the final location of the service, the original or home server 

sends the response back to the client.”); Pfister, In 

Search of Clusters (1995) (“Pfister”) (Ex. 1037) at 

78 (processing node in a cluster may “dynamically 

move work from one internal node to another to 

better balance the node”), 226-228 [J.A. 13926–

28]; Ex. 1012 [Garland et al., Implementing Distributed Server Groups for the World Wide Web

(1995)] at 8 [J.A. 12427] (“We could also extend 

the dispatcher to support anonymous members. It 

is conceivable that some servers might not want to 

advertise their location to the rest of the world. In 

this case, the dispatcher could serve as an intermediary between the client and the anonymous 

server.”) (emphasis added). And performing such 

routing was known to free up CPU cycles and 

memory resources of the sending device – that is 
MICROSOFT CORP. v. PARALLEL NETWORKS LICENSING 17

why the requests are routed away. See, e.g., Ex. 

1036 [Berson] at 9; Ex. 1037 [Pfister] at 226-228

[J.A. 13926–28]; Ex. 1012 [Garland] at 1 [J.A. 

12420] (“When the volume of requests to a server 

becomes prohibitively high the server tends to 

drop requests and eventually crashes. The service 

provider needs more computing power to meet the 

demands of the clients requesting the service. ... A 

fairly obvious solution to this problem is to implement a distributed Web server which will spread 

incoming request load among several machines.”)

(emphasis added). A person of ordinary skill in the 

art would therefore have been motivated to employ such a technique in the scheme of SWEB 95, 

which is expressly concerned with the efficient use 

of server resources. See Ex. 1009 [SWEB] at 2

(“Several resource constraints affect the performance of the server: the CPU speed and memory 

size of one processing unit, the existing system 

load, the transmission bandwidth between the 

processing unit and its local disk, the network latency and bandwidth between a processing unit 

and a remote disk when the accessed files are not 

stored in the local disk, and disk contention when 

multiple I/O requests access the same disk, can all 

affect the performance. Server scalability is 

achieved by actively monitoring the run time 

CPU, disk IO, and network loads of system resource units, and dynamically scheduling user 

HTTP requests to a proper node for efficient processing.”). Moreover, to do so would have been 

within the level of ordinary skill in the art, as the 

prior art shows, and merely the application of a 

prior art technique for its known purpose to 

achieve a predictable result.

J.A. 11449–51.
18 MICROSOFT CORP. v. PARALLEL NETWORKS LICENSING

The Board, referring to this testimony, concluded that 

Microsoft had not explained why a person of ordinary skill 

in the art would have been motivated to modify SWEB’s 

URL redirection, because, it determined, the stated 

benefits of request forwarding were already provided by 

URL redirection. IPR-483 Final Decision, 2016 WL 

8944632, at *9. This reasoning is inadequate. It does not 

address the legal significance, in light of some of the KSR

formulations, of Dr. Mitzenmacher’s statement, which is 

amply supported by references of record, that request 

forwarding was a well-known technique for a requestreceiving server to use to get another server to provide the 

client the desired information. It does not address the 

statement that an interest in anonymity is a reason for 

request forwarding. It does not address the statements in 

SWEB itself suggesting that the “best situation” might be 

to use a form of request forwarding (by UNIX socket 

modification) and identifying a “disadvantage” of URL 

redirection. SWEB at 10, 11.

In these circumstances, we conclude that the Board 

failed to provide adequate reasoning to support its determination on the component of the obviousness analysis it 

said was decisive. That inadequacy, together with the 

failure to consider the contention that SWEB teaches 

UNIX sockets modification, requires vacatur of all of the 

Board’s obviousness rulings. We remand for reconsideration of obviousness.

IV

For the foregoing reasons, we affirm the Board’s claim 

construction and rejection of anticipation by the URL 

redirection embodiment of SWEB. We vacate the rejection of anticipation based on the UNIX socket modification teaching in SWEB and the rejection of the 

obviousness challenge. We remand for further proceedings consistent with this opinion.

No costs.
MICROSOFT CORP. v. PARALLEL NETWORKS LICENSING 19

AFFIRMED IN PART, VACATED IN PART, AND 

REMANDED