Document ID: s3://data.kl3m.ai/documents/govinfo/USCOURTS/USCOURTS-ca13-09-01372/USCOURTS-ca13-09-01372-5/pdf.json

Parties Involved:
Akamai Technologies, Inc.
Appellant
Limelight Networks, Inc.
Cross-Appellant
Massachusetts Institute of Technology
Appellant

Document Text:

United States Court of Appeals 

for the Federal Circuit ______________________ 

AKAMAI TECHNOLOGIES, INC.,

THE MASSACHUSETTS INSTITUTE OF 

TECHNOLOGY,

Plaintiffs-Appellants

v.

LIMELIGHT NETWORKS, INC.,

Defendant-Cross-Appellant

______________________ 

2009-1372, 2009-1380, 2009-1416, 2009-1417

______________________ 

Appeals from the United States District Court for the 

District of Massachusetts in Nos. 06-CV-11585, 06-CV11109, Judge Rya W. Zobel.

______________________ 

Decided: November 16, 2015

______________________ 

SETH P. WAXMAN, Wilmer Cutler Pickering Hale and 

Dorr LLP, Washington, DC, argued for plaintiffsappellants. Also represented by THOMAS G. SAUNDERS, 

THOMAS G. SPRANKLING; MARK C. FLEMING, ERIC F.

FLETCHER, LAUREN B. FLETCHER, BROOK HOPKINS, Boston, 

MA; DAVID H. JUDSON, Law Offices of David H. Judson, 

Dallas, TX; DONALD R. DUNNER, ELIZABETH D. FERRILL, 

Finnegan, Henderson, Farabow, Garrett & Dunner, LLP, 

Washington, DC; JENNIFER S. SWAN, Palo Alto, CA; 

ROBERT S. FRANK, JR., G. MARK EDGARTON, CARLOS 

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2 AKAMAI TECHNOLOGIES, INC. v. LIMELIGHT NETWORKS, INC. 

PEREZ-ALBUERNE, Choate, Hall & Stewart, LLP, Boston, 

MA. 

AARON M. PANNER, Law Office of Aaron M. Panner, 

P.L.L.C., Washington, DC, argued for defendant-crossappellant. Also represented by JOHN CHRISTOPHER 

ROZENDAAL, MICHAEL E. JOFFRE, Kellogg, Huber, Hansen, 

Todd, Evans & Figel, P.L.L.C., Washington, DC; MICHAEL 

W. DE VRIES, ALLISON W. BUCHNER, Kirkland & Ellis LLP, 

Los Angeles, CA; YOUNG JIN PARK, New York, NY; DION 

D. MESSER, Limelight Networks, Inc., Tempe, AZ. 

JEFFREY I.D. LEWIS, Fried, Frank, Harris, Shriver & 

Jacobson LLP, New York, NY, for amicus curiae American Intellectual Property Law Association. Also represented by KRISTIN M. WHIDBY, Washington, DC; LISA K.

JORGENSON, American Intellectual Property Law Association, Arlington, VA.

SCOTT A.M. CHAMBERS, Porzio, Bromberg & Newman, 

P.C., Washington, DC, for amicus curiae Biotechnology 

Industry Organization. Also represented by CAROLINE 

COOK MAXWELL; HANSJORG SAUER, Biotechnology Industry Organization, Washington, DC.

CHARLES R. MACEDO, Amster Rothstein & Ebenstein 

LLP, New York, NY, for amicus curiae Broadband iTV, 

Inc. Also represented by JESSICA CAPASSO. 

PAUL H. BERGHOFF, McDonnell, Boehnen, Hulbert & 

Berghoff, LLP, Chicago, IL, for amicus curiae Intellectual 

Property Owners Association. Also represented by PHILIP 

S. JOHNSON, Johnson & Johnson, New Brunswick, NJ; 

KEVIN H. RHODES, 3M Innovative Properties Co., St. Paul, 

MN; HERBERT C. WAMSLEY, Intellectual Property Owners 

Association, Washington, DC. 

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AKAMAI TECHNOLOGIES, INC. v. LIMELIGHT NETWORKS, INC. 3

CARTER G. PHILLIPS, Sidley Austin LLP, Washington, 

DC, for amicus curiae Pharmaceutical Research and 

Manufacturers of America. Also represented by JEFFREY 

P. KUSHAN, RYAN C. MORRIS; DAVID E. KORN, Pharmaceutical Research and Manufacturers of America, Washington, DC; DAVID R. MARSH, LISA A. ADELSON, Arnold & 

Porter, LLP, Washington, DC; ROBERT P. TAYLOR, MONTY 

AGARWAL, San Francisco, CA. 

DEMETRIUS TENNELL LOCKETT, Townsend & Lockett, 

LLC, Atlanta, GA, for amici curiae Nokia Technologies 

Oy, Nokia USA Inc.

DONALD R. WARE, Foley Hoag LLP, Boston, MA, for 

amicus curiae The Coalition for 21st Century Medicine. 

Also represented by MARCO J. QUINA, SARAH S. BURG. 

______________________ 

Before PROST, Chief Judge, LINN and MOORE, Circuit 

Judges.

LINN, Circuit Judge. 

This case first came to this court after, inter alia, a jury verdict finding Akamai’s U.S. Pat. No. 6,108,703 (“’703 

patent”) not invalid and directly infringed by Limelight, 

followed by the entry of judgment as a matter of law 

(“JMOL”) overturning the jury’s infringement verdict on 

the basis of divided infringement. Akamai Techs., Inc. v. 

Limelight Networks, Inc. (Akamai II), 614 F. Supp. 2d 90 

(D. Mass. 2009). After several rounds of appeals and 

remands, culminating with the en banc court’s reversal of

the district court’s JMOL determination on the divided 

infringement issue, the case returns to this panel, which

is tasked with resolving “all residual issues” in the appeal 

and cross-appeal. Akamai Techs., Inc. v. Limelight Networks, Inc. (Akamai IV), 797 F.3d 1020, 1025 (Fed. Cir. 

2015) (en banc).

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4 AKAMAI TECHNOLOGIES, INC. v. LIMELIGHT NETWORKS, INC. 

On this record, the only issues remaining stem from 

Limelight’s cross-appeal, which argued alternative 

grounds for overturning the jury’s verdict of infringement 

and challenged the damages award. Specifically, three 

issues remain to be adjudicated. First, whether the 

district court erred in construing the claim term “tagging.”1 Second, whether the district court properly constructed the term “optimal,” and properly instructed the 

jury on the construction.2 Third, whether the district 

court erred in allowing Akamai to present a lost profits 

theory based on the testimony of its expert. 

Because the district court did not err in its claim constructions and appropriately instructed the jury, and 

because we find no error in the district court’s allowance 

of Akamai’s lost profits expert, we decline Limelight’s 

invitation to find an alternate basis to overturn the jury 

verdict on infringement and its damages award. Accordingly, we reiterate the en banc court’s reversal of the 

district court’s grant of JMOL of non-infringement and 

remand with instructions to reinstitute the jury’s original 

verdict and damages award. We also confirm our previously reinstated affirmance of the district court’s judgment of non-infringement of U.S. Patent Nos. 6,553,413 

(the “’413 patent”) and 7,103,645 (the “’645 patent”).

1 Limelight argues that the district court erred in 

its construction, and that the jury lacked sufficient evidence to find infringement in light of the correct construction.

2 Limelight argues both that the claim construction 

was erroneous, and that the subsequent jury instruction 

improperly left claim construction to the jury.

 

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I. BACKGROUND

A. The Technology and the Nature of the Dispute

A detailed description of the technology and the 

claims at issue in this case is set forth in the prior reported opinions of this court and the Supreme Court and will 

not be repeated except to the extent germane hereto. See

Akamai IV, 797 F.3d 1020; Limelight Networks, Inc. v. 

Akamai Techs., Inc., 134 S. Ct. 2111 (2014); Akamai 

Techs., Inc. v. Limelight Networks, Inc. (Akamai III), 629 

F.3d 1311 (Fed. Cir. 2010). 

B. Prior Proceedings

In 2006, Akamai sued Limelight in the United States 

District Court for the District of Massachusetts asserting 

infringement of claims 19–21 and 34 of the ’703 patent, 

along with certain claims of the ’413 and ’645 patents. 

After the district court’s first claim construction order, 

Akamai Techs., Inc. v. Limelight Networks, Inc., 494 F.

Supp. 2d 34 (D. Mass. 2007), Akamai stipulated that it 

could not prove infringement of the ’645 patent under the 

district court’s construction. The district court thus 

entered judgment of non-infringement. The district court

subsequently entered summary judgment of noninfringement of the asserted claims of the ’413 patent. 

As relates to the ’703 patent, the parties stipulated to 

a construction of “tagging” in claims 17, 19, and 34 of 

the ’703 patent as “providing a ‘pointer’ or ‘hook’ so that 

the object resolves to a domain other than the content 

provider domain.” Akamai Techs., Inc. v. Limelight 

Networks, Inc. (Akamai I), No. 06-11109, 2008 WL 

697707, at *1 (D. Mass. Feb. 8, 2008). The meaning of 

this term was not disputed until Limelight requested a 

jury instruction explaining that tagging could only be 

accomplished by “either prepending or inserting a virtual 

server hostname into the URL,” and filed Rule 50 motions 

for judgment of non-infringement because the accused 

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6 AKAMAI TECHNOLOGIES, INC. v. LIMELIGHT NETWORKS, INC. 

products did not tag in this way. The district court denied 

the requested jury instruction and the Rule 50 motions. 

The parties also stipulated that “to resolve to a domain other than the content provider domain” in claims 

17, 19, and 34 of the ’703 patent should be construed as 

“to specify a particular group of computers that does not 

include the content provider from which an optimal server

is to be selected.” Akamai I, 2008 WL 697707 at *1 (emphasis added). However, the parties disagreed on the 

meaning of the word “optimal” in the construction, with 

Limelight arguing that a single optimal server must be 

selected, and Akamai arguing that several servers could 

be “optimal” if they each met some criteria. Id. The 

district court construed “optimal server” as “requir[ing]

the selection of a content server that is better than other 

possible choices in terms of the criteria established by the 

specification.” Id. at *3.

Akamai’s claim that Limelight infringed the ’703 patent proceeded to a jury trial. The district court instructed the jury on “tagging” per the stipulation discussed 

above, and added the following gloss for “an optimal 

server”:

one or more content servers that are better than 

other possible choices considering some or all of 

the following criteria: (1) being close to end users;

(2) not overloaded; (3) tailored to viewers in a particular location; (4) most likely to already have a 

current version of the required file; and (5) dependent on network conditions. 

To prove damages, Akamai relied heavily on the testimony of its expert, Dr. Keith Ugone’s calculation of 

Akamai’s lost-profits. Dr. Ugone considered the elasticity 

of the market for content delivery network services, the 

competition between Akamai and Limelight, and the price 

disparity between Akamai’s and Limelight’s products. 

Ultimately, Dr. Ugone concluded that but-for Limelight’s 

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infringement, Akamai would have collected about $74 

million. 

The jury returned a verdict of infringement and 

awarded Akamai approximately $40 million in lost profits, $1.4 million in reasonable royalty damages, and $4 

million in price erosion damages. As noted, supra, the 

district court did not let the verdict stand and, instead, 

granted JMOL of no infringement. Akamai II, 614 F. 

Supp. 2d at 96.

Akamai appealed the district court’s rulings regarding 

all three patents-in-suit and Limelight cross-appealed. 

This court rejected Akamai’s argument that Limelight’s 

cross-appeal was improper, Akamai Techs., Inc. v. Limelight Networks, Inc., No. 2009-1372, 2010 WL 331770 

(Fed. Cir. Jan. 27, 2010) (Order), and subsequently affirmed the district court’s rulings regarding the ’413 

and ’645 patents. Akamai III, 629 F.3d at 1322–31. The 

portion of this court’s Akamai III opinion dealing with 

the ’645 and ’413 patents, though initially vacated upon 

grant of en banc rehearing, Akamai Techs., Inc. v. Limelight Networks, Inc., 419 F. Appx 989 (Fed. Cir. 2011), 

was later reinstated, see Akamai Techs., Inc. v. Limelight 

Networks, Inc., 786 F.3d 899, 903-904 (Fed. Cir. May 13, 

2015) (explaining procedural history), overruled en banc 

on other grounds by Akamai IV, 797 F.3d 1020. As noted, 

supra, this court reversed the non-infringement judgment 

and returned the case to this panel for resolution of all 

residual issues. Akamai IV, 797 F.3d at 1025. 

This court has jurisdiction pursuant to 28 U.S.C. § 

1295(a)(1).

II. DISCUSSION

A. Standard of Review

The “ultimate interpretation” of a claim term, as well 

as interpretations of “evidence intrinsic to the patent (the 

patent claims and specifications, along with the patent’s 

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prosecution history),” are legal conclusions, which this 

court reviews de novo. Teva Pharms. USA, Inc. v. Sandoz, 

Inc., 135 S. Ct. 831, 841 (2015). Review of the district 

court’s interpretation of the parties’ pre-trial stipulations 

is “much like” review of any contract interpretation, see

Scanner Techs. Corp. v. ICOS Vision Sys. Corp. N.V., 528 

F.3d 1365, 1383 (Fed. Cir. 2008): this court reviews underlying factual findings for clear error and reviews the 

ultimate interpretation of the stipulation de novo, see

Teva, 135 S. Ct. at 837–38.

This court reviews challenges to jury instructions, 

grants or denials of motions for JMOL, and questions of 

judicial estoppel under the law of the regional circuit 

where the district court sits. See AbbVie Deutschland 

GmbH & Co., KG v. Janssen Biotech, Inc., 759 F.3d 1285, 

1295 (Fed. Cir. 2014); Source Search Techs., LLC v. 

LendingTree, LLC, 588 F.3d 1063, 1071 (Fed. Cir. 2009). 

“When examining preserved claims of instructional error, 

[the First Circuit] afford[s] de novo review to questions as 

to whether jury instructions capture the essence of the 

applicable law, while reviewing for abuse of discretion the 

court’s choice of phraseology.” Ira Green, Inc. v. Military 

Sales & Servs. Co., 775 F.3d 12, 18 (1st Cir. 2015) (citations omitted). The First Circuit “review[s] the district 

court’s grant or denial of judgment as a matter of law de 

novo . . . viewing the evidence in the light most favorable 

to the verdict-winner, and vacating the jury verdict only if 

it lacks a sufficient evidentiary basis.” Kennedy v. Town 

of Billerica, 617 F.3d 520, 537 (1st Cir. 2010). The First 

Circuit “review[s] the district court’s decision not to 

invoke judicial estoppel for abuse of discretion . . . accept[ing] the trial court’s findings of fact unless they are 

clearly erroneous, and evaluat[ing] its answers to abstract 

questions of law de novo.” Knowlton v. Shaw, 704 F.3d 1, 

9–10 (1st Cir. 2013) (citations omitted). 

“Whether lost profits are legally compensable in a 

particular situation is a question of law that we review de 

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novo.” Siemens Med. Solutions USA, Inc. v. Saint-Gobain 

Ceramics & Plastics, Inc., 637 F.3d 1269, 1287 (Fed. Cir. 

2011).

B. Claim Construction

1. “[T]agging”

In a prior litigation relating to the ’703 patent, the 

district court construed “tagging” as “providing a ‘pointer’ 

or ‘hook’ so that the object resolves to a domain other than 

the content provider domain.” Akamai Techs., Inc. v. 

Digital Island, No. 00-11851-RWZ, 2001 WL 36172136, at 

*1 (D. Mass. Nov. 8, 2001). The district court defined “to 

resolve to a domain other than the content provider 

domain” as “to specify a particular group of computers 

that does not include the content provider from which an 

optimal server is to be selected.” Id. (emphasis added). 

The parties accepted these constructions by stipulation in 

the instant case. Akamai I, 2008 WL 697707 at *1. This 

construction was not disputed during the Markman

hearing, and was first challenged by Limelight in attempting to re-craft the construction for the jury instructions. 

Limelight argues that: 1) in the context of the ’703 patent, “tagging” is necessarily limited to using a “pointer” 

or “hook” that either prepends or inserts a virtual server 

hostname into the URL because the ’703 patent discloses 

no other way to “tag” to achieve the goals of the invention; 

and 2) that “alphanumeric string” as used in the ’645 

patent (and which this court has construed to necessarily 

include prepending or inserting a virtual server hostname 

in the URL) is the product of tagging in the ’703 patent, 

which necessarily means that the ’703 patent incorporates 

the same limitations as the ’645 patent. Akamai counters 

that: 1) Limelight waived the argument by failing to 

assert it during Markman and again failing to assert it 

after the jury instructions were read; 2) the stipulation to 

which Limelight agreed was made without further limitaCase: 09-1372 Document: 404-1 Page: 9 Filed: 11/16/2015
10 AKAMAI TECHNOLOGIES, INC. v. LIMELIGHT NETWORKS, INC. 

tion of the types of “hook” or “pointer” to use, and is thus 

binding on Limelight; 3) “tagging” in the ’703 patent is not 

equivalent to “alphanumeric string” in the ’645 patent; 

4) certain claims in the ’703 patent specifically require 

prepending while others don’t, and claim differentiation 

requires that the broader term “tagging” thus not be 

limited to prepending; 5) prepending is merely a preferred 

embodiment and Limelight is improperly attempting to 

limit the claim scope to a preferred embodiment; and 

6) Limelight argued that the asserted claims lacked 

written description because the specification taught that 

the only way to tag was to prepend a virtual hostname 

into an existing URL – but the jury rejected this argument.

Limelight’s attempt to import a “prepending” limitation into the claims fails. “[O]ur cases recognize that the 

specification may reveal a special definition given to a 

claim term by the patentee that differs from the meaning 

it would otherwise possess. In such cases, the inventor’s 

lexicography governs.” Phillips v. AWH Corp., 415 F.3d 

1303, 1316 (Fed. Cir. 2005) (en banc). However, a claim 

term is only given a special definition different from the 

term’s plain and ordinary meaning if the “patentee . . . 

clearly set[s] forth a definition of the disputed claim term 

other than its plain and ordinary meaning.” Thorner v. 

Sony Comput. Entm’t Am. LLC, 669 F.3d 1362, 1365 (Fed. 

Cir. 2012) (citations omitted). A patentee can also disavow claim scope, but the standard “is similarly exacting.” 

Id. at 1366. “[C]laims are not necessarily and not usually 

limited in scope simply to the preferred embodiment.” RF 

Del. v. Pac. Keystone Techs., Inc., 326 F.3d 1255, 1263 

(Fed. Cir. 2003).

The ’703 patent describes prepending as a “prefer[ence].” ’703 patent, col.4 ll.2–3. Figure 4 describes 

“prepend[ing a] virtual server host name,” but the patent 

likewise describes Figure 4 as showing the “preferred” 

method. Id. at col.6 ll.44–45. The patent’s reference to 

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preferred embodiments where the virtual server hostname is prepended does not provide the clarity necessary 

to find that the patentees intended to limit the term 

tagging to the preferred embodiment. Moreover, claim 17 

of the ’703 patent expressly recites “tagging . . . by prepending,” suggesting that the term “tagging”—without 

modification and as recited in the asserted claims—is not 

so limited. See Ancora Techs., Inc. v. Apple, Inc., 744 F.3d 

732, 735 (Fed. Cir. 2014) (explaining that using the 

phrase “application software program” in one claim, and 

“program” alone in another “tends to reinforce . . . adoption of the broad ordinary meaning of ‘program’ by itself”).

The prosecution history cited by Limelight also fails to 

provide the necessary clarity to limit “tagging” to the 

preferred embodiment. During prosecution, Akamai 

amended what is now claim 17 to require tagging “by 

prepending” and amended claim 19 to require that the 

content provider “serv[e] the given page” and that the

Content Delivery Network serve the embedded image. In 

their remarks, the applicants stated that “the embedded 

object URL is modified . . . to prepend given data to the 

domain name and path normally used to retrieve the 

embedded object.” In view of the amendment now requiring claim 17 to tag “by prepending,” a person of skill in 

the art could reasonably understand the applicants’ 

description of prepending the data as referring only to 

claim 17. This statement therefore does not provide the 

necessary clarity required for disavowal in claim 19. 

Limelight claims that the only method of tagging described in the ’703 patent involves prepending a virtual 

server hostname. However, as this court has held, “even 

where a patent describes only a single embodiment, 

claims will not be read restrictively unless the patentee 

has demonstrated a clear intention to limit the claim 

scope using words or expressions of manifest exclusion or 

restriction.” Innova/Pure Water, Inc. v. Safari Water 

Filtration Sys., 381 F.3d 1111, 1117 (Fed. Cir. 2004) 

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(internal citations omitted). As explained above, no such 

indication of exclusion appears in the patent specification 

or prosecution history.

We note that the district court read to the jury the 

construction of “tagging” to which Limelight stipulated. 

Though Limelight points to O2 Micro International Ltd. v. 

Beyond Innovation Technology Co., 521 F.3d 1351, 1361 

(Fed. Cir. 2008), for the proposition that its stipulation 

did not “give up any right to argue that further construction or interpretation of tagging would be needed,” that 

case is inapposite. In O2 Micro, the Court was clearly 

aware of the parties’ disagreement about the claim term 

“only if,” and the Court refused to construe it beyond its 

ordinary meaning. Id. at 1357 (“The parties agreed, for 

the most part, that a previously issued claim construction 

order . . . controlled in this case. . . . However, the parties 

presented a handful of additional terms for the court to 

construe [of which “only if” was one].”); id. at 1361 (“The 

parties presented a dispute to the district court regarding 

the scope of the asserted claims.”). See also id. at 1361 

(“[T]he parties disputed not the meaning of the words 

themselves, but the scope that should be encompassed by 

this claim language.” (emphasis in original)). Here, the 

parties agreed in the stipulation as to both the meaning 

and the scope of the term during claim construction: 

“tagging” means “providing a ‘pointer’ or ‘hook’ so that the 

object resolves to a domain other than the content provider domain.” This meaning was agreed-upon with no 

further limitations. The lack of further limitations was 

itself a characteristic of the construction to which both 

parties agreed. Limelight cannot argue at the jury instruction stage – after the bulk of the trial was framed 

and directed by the Markman construction to which it 

agreed – that the construction was somehow too broad. 

Limelight stipulated to a construction of “tagging,” and it 

is bound by that stipulation.

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We find no error in the district court’s claim construction of “tagging” or the jury instruction pursuant thereto. 

The parties do not assert that there is any remaining 

issue of fact as to whether Limelight performs “tagging” 

(apart from the “optimal server” issue addressed below).

2. “[A]n optimal server”

The second remaining dispute is whether “an optimal 

server” is necessarily limited to a single “best” server, or 

can refer to several potentially optimal servers from 

which content is retrieved.

The phrase “optimal server” does not appear in the 

patent. Instead, it is nested within the parties’ stipulated 

claim constructions as follows. “Tagging” was stipulated 

to mean “providing a ‘pointer’ or ‘hook’ so that the object 

resolves to a domain other than the content provider

domain.” The phrase “to resolve to a domain other than 

the content provider domain” was stipulated to mean “to 

specify a particular group of computers that does not 

include the content provider from which an optimal server

is to be selected.” Substituting the stipulated constructions into claim 19 results in the following, with emphasis 

added: 

19 [substituted]. A content delivery service, 

comprising . . . .

for a given page normally served from the 

content provider domain, providing a 

‘pointer’ or ‘hook’ to embedded objects 

on the page so that requests for those 

objects specify a particular group of 

computers that does not include the 

content provider from which an optimal server is to be selected

. . . . 

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serving at least one embedded object of 

the given page from a given content 

server in the domain instead of from 

the content provider domain.

During the Markman hearing, the parties disputed 

the meaning of “an optimal server.” The district court 

construed claim 19 to require “the content delivery system 

to serve an embedded object from one or more content 

servers which are ‘[m]ost favorable or desirable,’ that is, 

servers which meet some or all of the criteria described in 

the specification.” In the jury instruction, the district 

court elaborated on the criteria, explaining that “an 

optimal server” was: “one or more content servers that are 

better than other possible choices considering some or all 

of the following criteria: (1) being close to end users; (2) 

not overloaded; (3) tailored to viewers in a particular 

location; (4) most likely to already have a current version 

of the required file; and (5) depend[e]nt on network conditions.”

Limelight argues that: 1) the unambiguous meaning 

of “optimal” is necessarily restricted to a single aggregate 

“best” server; 2) the court’s ambiguous construction improperly left a claim construction issue for the jury; and 

3) Akamai is judicially estopped from arguing that “optimal” does not require a single “best” server by its statements equating “optimal” to “best.”

Limelight’s arguments are unconvincing. First, Limelight fails to appreciate the context of the selection of “an 

optimal server” in the claim. The selection of “an optimal 

server” describes the functionality enabled by the necessary “tagging.” In other words, the embedded objects are 

tagged such that a group of computers is identified, and 

from which an optimal server is chosen. The ’703 patent 

is replete with examples in which conditions or circumstances independent of the tag influence which server 

ultimately serves the embedded object. The tagging 

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described in the ’703 patent thus allows for the tag to 

ultimately lead to service from more than a single possible server. When the browser makes a request for an 

object, then the software on the ghost does the following: 

“If a copy of the file is already stored on the ghost, then 

the data is returned immediately. If, however, no copy of 

the data on the ghost exists, a copy is retrieved from the 

original server or another ghost server.” ’703 patent, 

col.12, ll.31-35. Similarly, the specification explains that 

the tagging allows “a ghost server [to] redirect the user to 

a closer server (or to another virtual address that is likely 

to be resolved to a server that is closer to the client).” Id.

at col.12, ll.44-47. And again, “[p]erformance for long 

downloads can also be improved by dynamically changing 

the server to which a client is connected based on changing network conditions.” Id. at col.12, ll.53-55. 

These examples undermine Limelight’s position in 

two ways. First, the tagging of the embedded objects 

provides the capability to select a server, and then select a 

different server – in other words, tagging enables the 

selection of one of several servers. Second, the criteria for 

server selection are not aggregated during tagging, 

wherein the system only allows serving from the single 

server that is the “winner” of the aggregated criteria. 

Instead, in one instance, a server may be chosen because 

it is closest to the user; in another instance, because 

another server does not have the file; and in yet another 

instance, because of overload of the server or network 

conditions. Choosing based on any of these criteria is 

indicated as a capability of the claimed tagging system – 

not merely choosing a single “aggregate best” server. 

Nothing in the patent limits the functionality of the tag to 

selecting an “aggregate best” – indeed, which criteria is 

ultimately decisive is not a function of the tag, but occurs 

while the objects are served.

This reading is confirmed by dependent claims 21 and 

22, which further limit the serving step in claim 19 to 

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16 AKAMAI TECHNOLOGIES, INC. v. LIMELIGHT NETWORKS, INC. 

“resolving a request to the domain as a function of a 

requesting user’s location,” ’703 patent, cl. 21, or “resolving a request to the domain as a function of a requesting 

user’s location and then-current Internet traffic conditions,” id. at cl. 22. In other words, determining the 

ultimate server from which the embedded object will be 

served using one particular criteria, or two criteria. 

Nothing in the specification or the claims implies that 

these two functionalities would necessarily return the 

aggregate best server, or that the two rules would return 

the same server. Limelight argues that this identification 

of “one or more content servers” is an additional step

identifying the list of all possible content servers from 

which the optimum server is selected. Limelight Supp. 

Opening Br. at 4. Limelight ignores that claim 20 is 

limiting “the serving step,” which occurs after the tagging 

step. 

Limelight’s argument that the “unambiguous” meaning of “optimal” is a single “best” is also unconvincing. As 

discussed above, the intrinsic evidence supports the 

district court’s construction. Moreover, neither the plain 

meaning of “optimal” nor the plain meaning of “best” is as 

limited as Limelight suggests to an “aggregate best” or 

“aggregate optimal.”

The district court’s construction did not improperly 

leave a claim construction issue for the jury by not construing a disputed term. The district court construed 

optimal server during the Markman hearing as described 

above, and elaborated during jury instructions that “an 

optimal server” was: “one or more content servers that are 

better than other possible choices considering some or all 

of the following criteria: (1) being close to end users; (2) 

not overloaded; (3) tailored to viewers in a particular 

location; (4) most likely to already have a current version 

of the required file; and (5) depend[e]nt on network conditions.” Nothing in the construction or the jury instructions requires the jury to construe the term. Limelight 

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AKAMAI TECHNOLOGIES, INC. v. LIMELIGHT NETWORKS, INC. 17

merely disagrees with the construction the district court 

adopted. 

Finally, Akamai’s use of “optimal” and “best” in the 

prior litigation does not estop Akamai from arguing that 

“optimal” allows for serving from other than a single 

composite best server because the point at issue in the 

discussions cited was distinct from the issue here. Limelight points to a colloquy wherein the district court questioned Akamai’s counsel about the functionality and 

sequencing of the tagging step, and Akamai’s counsel 

stated: “at some time during the serving of that object, 

picking the best computer to serve that object, that’s 

during the serving step, identifying the best computer,” 

and also agreed with the district court’s categorization 

that the process “is two steps. It tags to find the best 

domain and then also identifies the best computer or 

server within that domain.” Limelight’s reliance on this 

colloquy is misplaced. The discussion in that case was 

about the role of tagging, and Akamai’s attorney explained that the timing of the tagging step occurs with the 

selection of a domain, but that the selection of the “best 

computer” occurs during the object serving step. The 

issue of whether tagging enables serving from only a 

single “optimal server” or from a server which performs 

better than others within a particular criteria was never 

addressed.

For these reasons, there is no error in the district 

court’s construction of “an optimal server,” nor in the jury 

instruction.

C. Damages

To collect lost profits, a “patentee must show ‘a reasonable probability that ‘but for’ the infringing activity, 

the patentee would have made the infringer’s sales.” 

Ericsson, Inc. v. Harris Corp., 352 F.3d 1369, 1377 (Fed. 

Cir. 2004) (citations omitted). This is done by determining what profits the patentee would have made absent the 

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18 AKAMAI TECHNOLOGIES, INC. v. LIMELIGHT NETWORKS, INC. 

infringing product. Id. This analysis must be supported 

by “sound economic proof of the nature of the market and 

likely outcomes with infringement factored out of the 

economic picture.” Id. (citing Grain Processing Corp. v. 

Am. Maize-Prods. Co., 185 F.3d 1341, 1350 (Fed. Cir. 

1999)). 

Limelight argues the district court committed legal 

error in allowing lost profits as a measure of damages 

because Akamai failed to show a causal connection between Limelight’s infringement and Akamai’s lost profits. 

Limelight argues that Dr. Ugone’s calculation of the share 

of Limelight’s customers that would have gone to Akamai 

absent Limelight’s infringement was arbitrary and not 

based in sound economic theory. The underlying basis for 

this argument is the price disparity between Limelight’s 

and Akamai’s products, which Limelight says Dr. Ugone 

either failed to incorporate into his analysis, or incorporated arbitrarily. Limelight’s arguments are inapposite.

Limelight originally sold a different, non-infringing

service than the one at issue in this case. Limelight’s 

infringing service was released in April of 2005. Dr. 

Ugone testified that in 2005 Akamai had a market share 

of 79.8% and Limelight had a market share of 5% and in 

2006 Akamai had a market share of 74.7% and Limelight 

had a market share of 10.7%. Dr. Ugone then calculated 

an adjusted market share3 for the years when Limelight’s 

infringing service was on the market and concluded that, 

assuming Limelight only sold its earlier software, Akamai’s market share would have been 81% in 2005 and 

79.9% in 2006. Because he did not have sufficient data to 

determine the market share for 2007, he assumed it 

would be the same as the market share for 2006. For the 

3 An adjusted market share is the calculated market share Akamai would have had absent infringement. 

 

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AKAMAI TECHNOLOGIES, INC. v. LIMELIGHT NETWORKS, INC. 19

sake of “conservatism,” Dr. Ugone reduced Akamai’s 

share by 3% and excluded the lowest earning 25% of 

Limelight’s customers who he categorized as particularly 

price sensitive consumers, who may be unlikely to purchase a higher-priced alternative without Limelight’s 

infringing products in the market. Subject to these assumptions and modifications, Dr. Ugone opined that 

Limelight’s infringing sales totaled approximately $87.5 

million.

The lost profit analysis was complicated by the fact 

that Limelight sold its product for half the price of Akamai’s. This affected Dr. Ugone’s calculations in two ways. 

First, he assumed that in the but-for world where Limelight did not sell an infringing product, Akamai would sell 

its product to some of those customers for twice as much 

as Limelight had. Second, because of the difference in 

price between Akamai’s product and Limelight’s product, 

Dr. Ugone assumed that the demand for Akamai’s product would be 25% less than the demand for Limelight’s 

infringing products. Dr. Ugone explained that, in economics, how a change in price affects a change in demand is 

described as “elasticity.” The more elastic the demand, 

the more sensitive it is to change. A demand is described 

as “inelastic” if, when the price changes by a certain 

percentage, the demand changes by a smaller percentage. 

As Dr. Ugone explained, “if you change prices by 10 

percent and quantity demanded changes by only 5 percent . . . that’s an example of something we call inelastic.” 

Dr. Ugone opined that the demand for Akamai’s products was relatively inelastic (i.e. relatively priceinsensitive) and provided two justifications for calculating 

that 75% of Limelight’s sales would potentially have been 

made by Akamai. First, because Akamai’s costs were 

“revenue-generating costs,” customers would be more 

willing to expend money to buy Akamai’s product. Second, though there would be some “price sensitivity” such 

that some of Limelight’s customers would not purchase 

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20 AKAMAI TECHNOLOGIES, INC. v. LIMELIGHT NETWORKS, INC. 

the higher-priced Akamai product, the demand was 

relatively inelastic – meaning the quantity demanded 

would not change as much as the price changed. The 

relative inelasticity of demand was supported by Akamai’s evidence that Akamai and Limelight were direct 

competitors, including statements by Limelight that 1) 

Akamai was its largest competitor; 2) “Limelight and 

Akamai are, from a scale and quality standpoint, head 

and shoulders above the rest of . . . Limelight’s competition”; 3) demand was driven by end-users not customers; 

and 4) Akamai maintained a dominant market share 

despite Limelight’s infringing service and lower price. Dr. 

Ugone conceded that in picking 75% he “had to make a 

judgment call based on the attributes and come to a 

conclusion what the adjustments would be.” Based on his 

assumptions, Dr. Ugone determined that Akamai’s lost 

profits were about $74 million.

The considerations outlined above sufficiently support 

the district court’s decision to allow Dr. Ugone’s adjusted 

lost-profits analysis. This court has repeatedly approved 

similar adjusted market share analyses for estimating 

lost profits. See, e.g. Ericsson, 352 F.3d at 1377–80. 

There is no basis for Limelight’s claim that such an analysis here is legally unavailable. 

Limelight’s argument appears to be that the price 

disparity between Akamai’s and Limelight’s prices necessarily created a market segmentation in which Akamai 

was separate from Limelight. Limelight’s argument rests 

on BIC Leisure Prods., Inc. v. Windsurfing International, 

Inc., 1 F.3d 1214 (Fed. Cir. 1993), where this court determined that lost profits were unavailable because the 

accused infringer and the patentee serviced different 

markets based on a 60–80% price disparity. Limelight 

argues that in the face of a 100% price disparity, lost 

profits are legally unavailable. However, this court’s 

decision in BIC did not rest solely on the price disparity of 

the two companies. For one, the court noted that “[the 

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AKAMAI TECHNOLOGIES, INC. v. LIMELIGHT NETWORKS, INC. 21

patentee] Windsurfing concentrated on the One Design 

class hull form and BIC [the infringer] did not. Windsurfing’s boards differed fundamentally from BIC’s boards.” 

Id. at 1218. Moreover, the court explained that “at least 

fourteen competitors vied for sales in the sailboard market.” Id. In the instant case, in contrast, Akamai presented evidence that Akamai and Limelight were direct 

competitors, and the two leaders in the field, with capabilities and infrastructure beyond those of its competitors. 

Next, the court in BIC explained that the “record contains 

uncontradicted evidence that demand for sailboards is 

relatively elastic.” Id. Again, the instant case is different

- Dr. Ugone explained that the market was relatively 

inelastic, and set forth a number of reasons, discussed 

above, for this conclusion. Furthermore, the court noted 

that Windsurfing had licensed its patent to two competitors, both selling Boards similar to the patentee’s Boards 

at significantly lower prices. Id. Finally, there was 

evidence that Windsurfing’s “sales continued to decline 

after the district court enjoined BIC’s infringement,” but 

that the market share indeed went to one of the patentee’s licensees. Id. No such evidence exists here.

In conclusion, Dr. Ugone’s 25% adjustment for market 

elasticity was sufficiently grounded in economic principles 

for the district court to allow it. Though Limelight is 

correct that its customers expressed a clear preference for 

lower-priced products — as evidenced by their buying 

Limelight’s significantly cheaper product — and therefore 

would have been less likely to buy Akamai’s products 

than the average consumer, Dr. Ugone’s testimony took 

this consideration into account both in excluding the 

lowest 25% of Limelight’s customers from his lost profits 

analysis, and for discounting the potential award for price 

elasticity. Whether this discount was sufficient is not a 

legal challenge to the availability of lost profits, but as to 

the amount of lost profits, which Limelight failed to 

address in its panel briefing.

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22 AKAMAI TECHNOLOGIES, INC. v. LIMELIGHT NETWORKS, INC. 

For the first time in supplemental briefing, Limelight 

attempts to challenge the evidentiary basis for the 

amount of the jury’s award, as distinct from the legal 

challenge to the availability of lost profits. Also for the 

first time in the supplemental briefing, Limelight argues 

that Dr. Ugone’s 3% downward adjustment of Akamai’s 

adjusted market share indicates an internal inconsistency, because the reduction was not carried through into the 

lost profits calculation. Because the supplemental briefing was limited to arguments contained in the panel 

briefing, Akamai Techs., Inc. v. Limelight Networks, Inc., 

2009-1372 (Fed. Cir. Aug. 19, 2015) (non-precedential 

order) (“[T]he parties are requested to file letter briefs 

supplementing the original briefing of Limelight’s crossappeal and limited to the issues raised therein.” (emphasis 

added)), we need not consider this argument. Even if we 

were to consider it, we find it unconvincing. 

Limelight also appears to argue that the jury’s damages award “was unfairly tainted by the district court’s 

refusal to instruct the jury that it should reject a los[t] 

profits claim based on speculative evidence.” This argument is without merit. The district court did instruct the 

jury that “[t]he amount of lost profits must be proved with 

reasonable certainty and cannot be left simply to speculation.” The district court’s instructions captured the 

applicable law.

III. CONCLUSION

The en banc court reversed the district court’s grant of 

Limelight’s motion for JMOL of non-infringement of 

the ’703 patent. For the foregoing reasons, we conclude 

that the outstanding arguments in Limelight’s crossappeal have no merit. Thus, this case is remanded with 

instructions to reinstate the jury verdict and the jury’s 

damages award. This court’s previously reinstated affirmance of the district court’s judgment of nonCase: 09-1372 Document: 404-1 Page: 22 Filed: 11/16/2015
AKAMAI TECHNOLOGIES, INC. v. LIMELIGHT NETWORKS, INC. 23

infringement of the ’413 and ’645 patents is also reconfirmed. 

AFFIRMED-IN-PART, REVERSED-IN-PART, AND 

REMANDED

COSTS

Each party shall bear its own costs.

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