emc corp. v. zerto, inc., c.a. no. 12-956-gms

8/11/2019 EMC Corp. v. Zerto, Inc., C.A. No. 12-956-GMS

http://slidepdf.com/reader/full/emc-corp-v-zerto-inc-ca-no-12-956-gms 1/20

IN THE UNITED STATES DISTRICT COURTFOR THE DISTRICT OF DELAWARE

EMC CORPORATION AND EMC ISRAELDEVELOPMENT CENTER, LTD.,

Plaintiffs,

v

ZERTO, INC.,

Defendant.

)

)

Civil Action No. 12-956-GMS

)

ORDER CONSTRUING THE TERMS OFU.S. PATENT NOS. 7,647,460; 6,073,222; 7,603,395; 7,971,091; and 7,577,867

After having considered the submissions o the parties, and hearing oral argument on the

matter, IT IS HEREBY ORDERED, ADJUDGED, and DECREED that, as used in the asserted

claims o U.S. Patent Nos. 7,647,460 ( the '460 patent ), 6,073,222 ( the '222 patent ),

7,603,395 ( the '395 patent ), 7,971,091 ( the '091 patent ), and 7,577,867 ( the '867 patent ):

A. The '460 patent

1 The term storage system is construed to mean the set o components thatstores and controls the storage o information written from the CPU, includingone or more storage devices and one or more controllers.

The parties' dispute over this term is whether storage system can include components

other than storage devices and storage controllers. The court agrees with the plaintiffs EMC

Corporation and EMC Israel Development Center, Ltd. ( EMC ) that storage system should be

construed according to its customary meaning because the inventors did not provide an express

definition or disavow claim scope. (D.I. 88 at 2-3.) See Aventis Pharma S.A. v Hospira Inc.

675 F.3d 1324, 1331 (Fed. Cir. 2012) (stating claim terms are to be construed according to their

ordinary and customary meaning unless the patentee expressly defines the term or disavows the



full claim scope.); Abbott Labs. v Sando= Inc. 566 F.3d 1282, 1288 (Fed. Cir. 2009) ( [The]

court will not limit broader claim language to [a] single [embodiment] unless the patentee has

demonstrated a clear intention to limit the claim scope using words or expressions o manifest

exclusion or restriction. ).

Accordingly, the Court rejects the defendant Zerto, Inc.'s ( Zerto ) proposed

construction -- the combination o a storage device and its storage controller. (D.I. 87 at 5.)

While the specification does state that the mirroring target storage system is controller 7 and

storage device 9 and that the source storage system is controller 5 and storage device 3

(' 460 patent, 1:5 1-55), that language describes prior art that does not include additional

components associated with the present invention. In addition, the specification identifies

EMC's SYMMETRIX line o disc arrays as one example o a storage device, id. at l :23-25),

which is described as containing several types o controllers, such as host and disk controllers,

for controlling the various aspects o the data transfers associated with the storage system ,

(D.l. 89 Ex. 3 1 24-55).

Similarly, the court is not persuaded by Zerto's argument that the network RDF controller

and network interface units cannot be part o the storage system because the specification

explains that the network components interface the storage system to the network cloud. (D.I.

87 at 6.) The pertinent specification language teaches:

As shown in FIG. 2 the remote mirroring data facility can includesome additional hardware to interface both the source and targetstorage systems to the network cloud. In particular, on each side o

the illustrative remote mirroring data facility shown in FIG. 2 isprovided a network remote data facility (RDF) controller and oneor more network interface units.

(' 460 patent, 6:55-62) The court finds that the cited language does not amount to words or

expressions o manifest exclusion or restriction that demonstrate an intent to preclude the

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network components and controllers from being part of the storage system. Abbott Labs., 566

F.3d at 1288 Accordingly, Zerto's proposed construction is improper because the specification

teaches that the storage system may contain a variety of controllers.

EMC contends, and the court finds no reason to disagree, that in the context of the '460

patent, the customary meaning of storage system to a person of skill n the art is the set of

components that work together to store information written from the CPU. 1 (D.I. 88 at 2.) As

such, the court adopts EMC's proposal and construes storage system to mean the set of

components that stores and controls the storage o f information written from the CPU, including

one or more storage devices and one or more controllers. Id.) The court disagrees with Zerto

that the construction is vague because it does not identify what other components might be

involved in stor[ing] and control[ling] the storage of information. (D.I. 87 at 6.) See Acumed

LL v Stryker Cmp., 483 F.3d 800, 806 (Fed. Cir. 2007) ( [A] sound claim construction need

not always purge every shred of ambiguity. The resolution of some line-drawing problems is

properly left to the trier of fact. ); PPG Indus. v Guardian Indus. Corp., 156 F.3d 1351, 1355

(Fed. Cir 1998) ( [A]fter the court has defined the claim with whatever specificity and precision

is warranted by the language of the claim and the evidence bearing on the proper construction,

the task of determining whether the construed claim reads on the accused product is for the

finder of fact. ). Here, the patentee used the broad term system, which allows for the inclusion

of components not identified in the specification's simplified storage system, so long as the

additional components serve the common purpose of storing information written from the CPU.

1 EMC relies on extrinsic evidence to establish the term's customary meaning. In 1994, the IEEETechnical Committee on Mass Storage Systems and Technology defined storage system as: a set of

devices, associated software, operators, physical processes, etc., that provides services for the storage andretrieval of data. (D.I. 94 at JA209.) Similarly, the 1997 edition ofWebster s Dictionary of ComputerTerms defines system as: an organized collection o f components that have been optimized to worktogether in a functional whole. ld. at JA241.)

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2. The term to mirror at least some of the information writ ten from theCPU to the first storage system in the second storage system is construedto mean maintain a continually updated copy of data that exists on a firststorage system on a second storage system by creating, in essentially realtime, an identical copy of at least some of the information written from theCPU to the first storage system in the second storage system.

Zerto argues that the term mirror should be construed to mean create an identical copy

of data that exists on one system on a second system. (D.I. 87 at 7-8.) EMC objects to that

proposal on the basis that it encompasses a wide-range of techniques that are not mirroring,

including backup techniques that the applicants distinguished during prosecution. (D.I. 88 at 4.)

EMC contends that mirroring refers to the process of maintaining a continually updated copy

of data by copying writes to one storage system to another storage system in essentially real

time. (D.I. 92 at 3.) The court finds that EMC's definition is supported by the intrinsic record

and claim language. The specification teaches that [a]s data is written to the source storage

device, it can also be written and mirrored to the target storage device. (' 460 patent, 1:39-41.)

During prosecution the applicants argued that mirroring updates are made in essentially real-

time, while a backup operation is typically performed off-line. (D.L 94 at JA144.) In

addition, the continually updated limitation is supported by the claims, which require a

mirroring controller (or controller ) to mirror information in response to or responsive to

the information being written from the CPU to the storage system. The applicants added the

responsive language during prosecution to clarify that mirroring occurs as data is written to a

first storage system, and not later in response to a backup utility being run. See id. at JA 166.)

EMC further argues in its briefing that the phrase at least some in the claims reflects

that a CPU running multiple applications writes data related to those different applications to

different portions of a storage system. And an administrator may wish to mirror only the data

written by the CPU for one of the applications and not others. Thus, EMC argues that its



proposed construction encompasses this scenano by explaining that mirroring creates a

continually updated copy of data that exists on the portion of the storage system that stores data

for the application that the administrator wishes to mirror. (D.I. 92 at 3-4.) While that may be a

plausible interpretation o f the claim language, the court finds that neither the specification nor

prosecution history provides such an explicit teaching or explanation. Accordingly, the court

does not fully adopt EMC's proposed construction. 2 Instead, the court combines aspects o f both

parties' proposals and construes the term to mean to maintain a continually updated copy of data

that exists on a first storage system on a second storage system by creating, in essentially real-

time, an identical copy o f at least some of the information written from the CPU to the first

storage system in the second storage system. The court's construction conveys the concept of

mirroring described in the intrinsic record without imposing unsupported limitations.

3 The term to mirror at least some o the information written from theCPU to the first storage system in both the second and third storagesystems is construed to mean maintain a continually updated copy of datathat exists on a first storage system on the second and third storage systems bycreating, in essentially real-time, an identical copy o f at least some o f the

information written from the CPU to the first storage systemn

both thesecond and third storage systems.

4. The term means for mirroring is construed pursuant to 35 U.S.C. §112, 6. The claimed function is mirroring at least some of the informationwritten from the CPU to the first storage system in the second storagesystem. The corresponding structure is source and target storage controllers,network RDF controller, network interface unit, and a network cloud.

The parties recognize that the term presents a means-plus-function limitation under §

112, 6 and correctly agree as to the claimed function. They are also largely in agreement with

regard to the corresponding structure. (D.I. 87 at 7; D.I. 88 at 5.) The parties' sole dispute is

whether a network cloud is part of the necessary structure.

EMC provides the following proposed construction: to maintain a continually updated copy of

data that exists on a portion of the first storage system on the second storage system by copying eachwrite to the portion of the first storage system to the second storage system. (D.I. 88 at 4.)

5



EMC argues that the network cloud does not perform the mirroring function; rather, it

is a conduit through which the data, mirrored by controllers, flows. (D.I. 92 at 5.) In contrast,

Zerto argues that the mechanism for mirroring the information from one storage system to the

other necessarily includes the network cloud in addition to the hardware on either side. t

emphasizes that without the cloud, the function of mirroring data from one storage system to

another cannot be accomplished. (D.I. 93 at 7.) The court finds Zerto's argument more

persuasive.

5. The term controller is construed to mean a component of the storagesystem that controls at least one function of the storage system.

The court adopts EMC's proposed construction. Zerto s construction- a device that

manages the operation of and connection to another device imposes improper limitations on

the disputed term. As a starting point, the specification does not restrict controller to only

devices. Indeed, the specification teaches that the storage controllers and network RDF

controllers may be implemented in numerous ways, including dedicated hardware, or as software

executed by any processor. ( 460 patent, 7:14-39.) In addition, Zerto's proposed construction is

inconsistent with the claim language. For example, in claim 38 the function of the controller is

to transfer at least some of the information written from the CPU into the network cloud so that

[it] can be mirrored in the target storage system. Zerto's proposal, however, would require that

the controller manage[] the operation of and connection to another device. Finally, Zerto

argues in its briefing that the manages the operation of limitation requires the controller to

perform all functions of the storage system. (D.I. 87 at 7.) The court rejects that premise. As

discussed above, the specification identifies prior art disk arrays that include several types of

controllers for controlling various aspects of the data transfers associated with storage systems.

As such, the court agrees with EMC that a person of ordinary skill in the art would have



understood that a storage system has numerous functions not expressly described in the patent,

and that the ordinary meaning o controller does not require it to control all o those functions.

(D.I. 92 at 6.) Therefore, the court rejects Zerto's proposed construction because it is inconsistent

with the claim language and not supported by the intrinsic record.

In contrast, EMC's proposal does not impose functional limitations on the generic term

controller. Rather, it explains to the jury that a controller controls at least one function, but

allows the function explicitly recited in each claim to speak for itself. Therefore, the court

adopts EMC's proposed construction.

B The '222 patent

L The term preservation memory is construed to mean storage used forpreserving data blocks.

The court rejects Zerto' s proposal - memory dedicated to holding a snapshot o a

portion o memory at the selected moment - because it limits preservation memory to a

preferred embodiment. t is improper to import limitations into claims from examples or

embodiments appearing only in a patent's written description, even when a specification

describes very specific embodiments o the invention or even describes only a single

embodiment, unless the specification makes clear that 'the patentee intends for the claims

and the embodiments in the specification to be strictly coextensive. ' JVW Enters. Inc. v.

Interact Accessories Inc. 424 F.3d 1324, 1335 (Fed. Cir. 2005) (quoting Phillips v. WH Corp.

415 F.3d 1303, 1323 (Fed. Cir. 2005)).

In contrast, the court agrees with EMC that preservation memory is simply memory

that preserves data. (D.I. 92 at 7.) The '222 patent teaches that preservation memory can be

any type o write able storage device ('222 patent, 9:5-11 , and that it stores (i.e., preserves)

data blocks o a mass storage system that are overwritten id. at 9:1-4 . In addition, the court

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agrees with EMC that Zerto's proposal would impermissibly limit the scope o f claims that

include preservation memory, but do not do not recite the snapshot concept. Compare

asserted claim 1 ( In a computer system including a mass storage system having a plurality of

data blocks and a preservation memory, a method for accessing data as it existed in the mass

storage system at a selected moment ) with unasserted claim 11 ( In a computer system

including a mass storage system having a plurality of data blocks and a preservation memory, a

method for accessing a snapshot of the mass storage system at a selected moment . . . ).)

Differences among claims can also be a useful guide in understanding the meaning of particular

claim terms. Phillips, 415 at 1314. Accordingly, the court adopts EMC's proposal and

construes preservation memory to mean storage used for preserving data blocks.

2 The term when a new block written to the mass storage system is tooverwrite the original data block is construed to mean in response to anew block written to the mass storage system that is to overwrite the originaldata block. 3

3 The term original data block is construed to have its plain and ordinary. 4meanmg.

C. The '395 and '091 patents 5 e the Bingham Patents )

1 The term event marker is construed to mean a data structure that includesinformation that can be used to identify a pseudosnapshot.

The court adopts EMC's proposed construction. Zerto's proposed construction requires

that the event marker must include the date and time at which the pseudosnapshot was

created. (D.I. 87 at 14.) The specification, however, states that event markers signify the

existence of a pseudosnapshot, ('395 patent, 15:30-31), and that it is a data structure that may

3 After submission o f claim construction briefing, but prior to oral argument, the parties reachedagreement as to the meaning o f this term. In the absence o f a genuine dispute, the court will not construethe term. See 2 Micro International Ltd. r Beyond Innovation Technology Co Ltd., 521 F.3d 1351,1360 (Fed. Cir. 2008); U S Surgical Corp. v Ethicon, Inc., 103 F.3d 1554, 1568 (Fed. Cir. 1997).

4 See Note 3, supra.5 The patents share a common specification. Therefore, the court will cite only the '395 patent.

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exemplarily contain information regarding the time at which the pseudosnapshot was created,

id., 13:56-58 (emphasis added)). The specification also describes an alternate embodiment

where the event marker's position in the write journal identifies the point in time in the series o

transactions stored in the write journal corresponding to a pseudosnapshot. Id., 15:62-65 ( [T]he

first entry [in the write journal] immediately after an event marker is created could also be used

to identify the existence o a pseudosnapshot. ).) At the Markman hearing, EMC's counsel

explained the two implementations o the event marker: one where you are placing [the event

marker] into the write journal, like putting [a] bookmark between the pages o the book, and one

where you are recording the date and time and you are not necessarily putting [the event marker]

in the write journal. (Transcript o Hearing, dated June 11 2014 ( Tr. ) at 50: 16-21.)

The court finds that the language o the asserted claims also reinforces two distinct event

marker embodiments. Claims 1 and 20 o the '091 patent expressly required that the event

marker identify the date and time at which the at least one pseudosnapshot is created. In

contrast, other asserted independent claims do not require the event marker to identify any date

and time information. For example, claim 1 o the '395 patent requires the event marker to

identify a point in time in the series o transactions. As such, it is an example o the alternate

embodiment where the event marker'' is placed or inserted into the series o transactions, and

there is no need for it to include the date and time information.

Accordingly, the court rejects Zerto's proposed construction because it improperly limits

the scope o the claim term to a single disclosed embodiment. On the other hand, EMC's

proposal -- a data structure that includes information that can be used to identify a

pseudosnapshot -- encompasses both disclosed embodiments. Therefore, the court adopts

EMC's proposed construction.



2 The term pseudosnapshot is construed to mean. a dataset, identified by anevent marker, within the continuous data protection system that can besurfaced

The patents describe an invention where write transactions from a production application

to a primary storage system are also stored in a separate location, referred to as a continuous data

protection ( CDP ) engine. By separately storing a copy o each write transaction, the CDP

engine is able to retain information about every change to a selected application, directory,

volume, or the like over a period o time, which allows the user to recover data as it appeared at

any given point in time in the past. ('395 patent, 2: 19-30.) The patents teach that the

application data may be recovered using one or more pseudosnapshots Id., 2:34-35.)

The parties agree that pseudosnapshot must be defined by the patents because the term

was coined by the inventors and has no customary meaning. (D.I. 88 at 12; D.I. 93 at 12.) The

patents explain that a conventional snapshot is a read-only point-in-time replica or

representation o the original contents o one or more volumes. ('395 patent, 3:46-48.) In

contrast, the patents state that [p ]seudosnapshots are earmarked data sets within the CDP

engine that can later be reliably surfaced as a copy. Jd., 3:33-35.) The patents further explain

that:

The snapshot is pseudo because while the pseudosnapshot datamay appear to have the properties o conventional read-onlysnapshot from the perspective o the snapshot manager 206, whena pseudosnapshot is created, no snapshot is actually created on anystorage disk. Instead, an event marker is created at the time thepseudosnapshot is created to allow a copy o the data to besurfaced from the CDP engine 110 up until the point in time at

which the event marker was created.

Jd. 14:4-12.) Thus, the patents clarify that pseudosnapshots are not snapshots, but rather

datasets earmarked by event markers. As such, a pseudosnapshot is the combination o a

dataset and an event marker. The court finds that EMC's proposed construction reflects that

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Once the pseudosnapshots have been created using the techniquesdescribed above, a user has the option o surfacing a copy whichcontains an image o any o the data actually corresponding to apseudosnapshot. The process o surfacing a copy includes theselection o a pseudosnapshot. For example, in one embodiment, auser may enter a time in the past up until which the user wishes tosurface a copy.After the user selects a pseudosnapshot, SCM 208C then surfaces acopy by reading the data stored in the CDP engine up until thepoint in time that the event marker corresponding to the selectedpseudosnapshot was created. SCM 208C formats this data into adata structure that has the appearance o a traditional snapshotfrom the perspective o snapshot manager 206 and replicationapplication 106.

('395 patent, 16:3-16 (emphasis added).) The specification further teaches that [i]f desired, the

surfaced copy can be formatted to have the properties o a conventional read-only snapshot.

Id., 14:12-14 (emphasis added).) And [o]nce computer 102 has surfaced a copy, the data on

the surfaced copy can be utilized similar t a traditional snapshot. ld., 7:27-28 (emphasis

added).) Accordingly, the court agrees with EMC that [t]he patents never state that the

generated data structure is a snapshot, and by contrasting the data structure with a snapshot, the

patents make clear that it isnot

a snapshot. (D.I.88

at 15.) As such, Zerto's proposedconstruction contradicts the thrust o the specification and improperly limits the scope o

surfacing by requiring it to generate a snapshot.

In addition, the court rejects Zerto's arguments that the entire point o the invention is

to surface data corresponding to an actual snapshot and that the phrase data structure is

inappropriately vague. (D.I. 87 at 19.) As discussed above, the patents are directed to surfacing

data associated with a pseudosnapshot that may appear to a user as but in fact is not a

conventional snapshot. See '395 patent, 7:27-28, 14:12-14, 16:3-16.) As such, the patented

invention is able to surface data that mimics a traditional/actual snapshot at a particular point in

time, but is not limited to only that function. Finally, the court finds that data structure is not

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vague because the specification uses that exact language when describing the act o surfacing.

See '395 patent, 16:13-16.) Therefore, the court adopts EMC's proposal and construes

"surfacing [a/the] copy o at least a portion o the series o transactions" to mean "generating

[a/the] data structure from the dataset o at least a portion o the series o transactions."

4. The term surfacing o a copy o transactions is construed to mean"generating a data structure from the dataset o a series o transactions."

5. The term surfacing o a copy o the at least a portion o the series o

transactions is construed to mean "generating a data structure from thedataset o the at least a portion o the series o transactions."

6. The term surfaced copy is construed to mean "data structure generated

from a dataset o transactions."

7. The term causes the production application to quiesce is construed tomean "instructs the production application to enter an inactive state whereinthe production application does not generate write operations."

The Bingham patents teach that a "quiesced" application is in an "inactive state." ('395

patent, 13:40-42.) The patents further describe the ability to recover data in an "application

consistent state," which the parties agree is "a point in time when all pending write operations

have been committed to disk.' (D.I. 99 at 3.) The parties also agree that to achieve an

application consistent state, the patents "teach taking the affirmative step o 'quiescing' a

production application prior to inserting an event marker in the write journal." (D.I. 88 at 17; D.I.

92 at 14; '395 patent, 18:32-34.) Zerto, however, argues that the applicant deliberately choose to

omit that "affirmative step" from the claims. (D.I. 92 at 14.) In addition, the parties dispute

whether an application must be instructed to quiesce, as EMC proposes, or whether an

application is "quiesced" when there is a pause in its write activity, as Zerto proposes.

EMC argues that "quiesce" is an active term and its customary meaning in the art

entering an inactive state in response to an instruction to do so requires some entity to "bring"

3



the production application into a quiescent state. 7 (D.I. 88 at 17; D.I. 92 at 15.) Consistent with

the customary meaning, the patents teach that in one embodiment, replication application 1 6

sends an instruction to production application 104 requesting the application to temporarily

quiesce (i.e., temporary [sic] enter an inactive state). ('395 patent, 13:38-41.) In other

embodiments, a configuration utility or the replication application places the production

application and a quiescent state. ( d., 12:41-44.) Therefore, EMC argues that in all o

embodiments, some component o the system instructs the production application to quiesce.

(D.I. 88 at 17.) The court agrees.

In addition, the court notes that it explicitly rejects Zerto's proposed construction: pause

write activity. (D.I. 87 at 17.) The specification warns that when a backup is created without

quiescing the application, it is likely that the backup occurred when the entire application was

not in a consistent state, but rather a crash consistent state. ('395 patent, 18:34-42.) Data

saved to the CDP engine is often in a crash consistent state because the CDP makes

continuous backups o an application's reads and writes, but is not cognizant o the needs o the

actual application. /d., 18:43-48.) Accordingly, the specification explains that to quiesce the

application prior to a backup operation is a technique used to obtain an application consistent

state, which requires more than merely pausing the application's write activity. See id., 18:27-

59.)

The disputed term appears in dependent claim 3 o the '395 patent, which adds the

7 The Storage Networking Industry Association defines quiesce as [t]o bring a device or anapplication to a state in which (a.) it is able to operate, (b.) all o its data is consistent and stored on nonvolatile storage, and (c.) processing has been suspended and there are no tasks in progress (i.e., allapplication tasks have either been completed or not started). (D.I. 94 at JA 272.) The same technicalreference defines quiescent state as an application or device state in which (a.) the application ordevice is able to operate, (b.) all o its data is consistent and stored on non-volatile storage, and (c.)processing has been suspended and there are no tasks in progress (i.e., all application tasks have eitherbeen completed or not started). ld.)

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quiescent state does not occur when write activity is merely paused. Indeed, the specification

explains that to quiesce the application prior to a backup operation is one technique used to

place the entire application [] in a consistent state, and that when a backup is created without

quiescing the application, it is likely that the backup occurred when the entire application was

not in a consistent state. ('395 patent, 18:3I-37.) As such, the court finds that a quiescent

state is an application consistent state that necessarily requires an instruction to the application

to quiesce. Achieving an application consistent state requires instructions to quiesce because

that would be the only way to ensure that multiple applications suspend their write operations

simultaneously, and that they do so in a manner that can be confirmed so that the backup

operation can be performed. While the court omits this language from its formal construction in

an effort to simplify the construction for the jury, the court's reasoning is fully incorporated into

the term ''quiescent state. And the parties shall not interpret the term quiescent state in a

manner inconsistent with the language as set forth above.

I0 The term write journal is construed to mean storage in which a series of

write transactions are stored along with information that can be usedto

identify an order of the write transactions. 10

II The term client file index is construed to mean an index of the backed updata items.

The court rejects EMC's proposal-- an index of client files --because it fails to add any

clarity to the claim term. In contrast, Zerto's proposal is drawn directly from the specification,

which states:

The server may also store and manage a client file index and amedia volume both on the server itself and/or on the backupstorage. The client fil e index is an index o f the backed up data

10 After submission o f claim construction briefing, but prior to oral argument, the partiesreached agreement as to the meaning of this term. In the absence o f a genuine dispute, the courtwill not construe the term. See 2 Micro lnt ' ., 521 F.3d at 1360; U S Surgical I03 F.3d at1568.

16



items The media volume is an index of the backed up volumes.The client file index and the media volume are collectively referredto herein as the online indices . The online indices are typicallystored on the backup storage after the backup operation is

complete. However, it will be appreciated that other operatingsystems may also use similar data structures for maintaining thedirectories and backed up items in order to restore the directoriesand items during recovery.

091 patent, 7:16-27 (emphasis added).) The disputed term only appears again in dependent

claims 3 and 6, which contain the additional limitation: wherein the remote server further

comprises a client file index configured to maintain a record of the surface copy. As such, the

specification clarifies that the specified client files are simply backed up data items.

Accordingly, the court adopts Zerto's proposal because it adds clarity to the claim language and

reflects the definition provided in the patent specification.

D. The '867 patent

1. The term data protection appliance (DPA) manager is construed to meana computer or a cluster of computers that receives a cross-tag instruction,

sends quiesce and tag commands, receives confirmations, and sends unquiesce commands.

The parties have agreed to a construction for data protection appliance ( DPA ),

(D.I.

99 at 2), but they disagree on the operations performed by the DPA manager, and whether the

DPA manager must itself be a DPA. 12 Claim 33 is representative of how the term is used in the

asserted claims:

A method for data protection, comprising issuing requests from a

The parti es' agreed-upon construction for DPA is a computer or a cluster o f computers thatserve as a data protection appliance, responsible for data protection services including inter alia datareplication of a storage system, and joumaling o f I / 0 requests issued by a host computer to the storagesystem by storing the I / 0 requests in a journal, which is a record o f write transactions used to maintainand rollback a duplicate storage system to a previous point in time.

2Zerto ' s proposed construction is a DPA that receives a cross-tag instruction, sends quiescence

and tag commands, receives confirmations, and sends un-quiesce commands. (D.I. 87 at 3.) In contrast,EMC asserts that a DPA manager is a computer or a cluster o f computers that issues requests to at leastone DPA. (D.I. 88 at 20.

17



data protection appliance (DPA) manager, to at least one DPAwithin at least one consistency group, G 1, . . . , Gn, the requestcompnsmg:

Zerto argues that EMC' s cannot be correct, because the specification is clear that, inaddition to issuing requests to at least one DPA, the DPA manager must also receive cross-tag

instructions (this is why it issues the requests) and confirmations (confirming that its requests

were received). (D.I. 93 at 18; '867 patent, 21:66-22:4, 23:23-31.) The court agrees.

In addition, the court agrees with Zerto that the system claimed in the '867 operates by

stopping the acknowledgment o l 0 requests and 'tagging' a consistency group to mark a point

in time. (D.I. 87 at 3.) The specification explains that this is done by a DPA manager, the

functionality o which is described with reference to method FIGS. 10 and 12. ('867 patent,

20:54-56.) Describing FIG.10, the specification teaches that the DPA manager receives an

instruction to tag, and then sends quiesce and tag commands to at least one DP A.

When a consistent image o G 1, G2 and G3 is to be created, one o

the DPA computers, referred to as the DPA manager , say C1,receives a cross tag instruction (step 1003). The DPA manager

initiates a timer at a timeTO,

with an elapse timeo TO .M

(step1006), and sends quiesce and tag commands to computers C 1, C2and C3 (step 1009). In accordance with a preferred embodiment o

the present invention, the module that performs the quiesce and tagcommands on Cl (steps 1012, 1015, 1018, 1021, 1024, 1045 and1048) runs on a different processing thread than the module thatissues the commands (steps 1003, 1006, 1009, 1027, 1030, 1036,I 039 and 1042).

('867 patent, 21:66-22:10.) After the DPAs qmesce and apply their tags, they send[] a

confirmation to the DP A manager that the quiesce and tag commands were successful, id.,

22:22-25), and then either the timer runs out or the DPA manager issues a command to un

quiesce, id., 22:25-28, 23:23-31). 13 Accordingly, the court finds that Zerto has correctly

13 The differences between FIGS.lO and 12 do not affect the court's construction. Thespecification explains the differences are a different timeout period and different logic steps for

18



identified the functions performed by the DP A manager.

However, the court agrees with EMC that the claim structure does not require the DP A

manager to be a DP A. At the Markman hearing, EMC argued that the language of a dependent

claim requires that the DPA manager must be [construed] broad enough to include a separate

generic appliance, which is a computer or a cluster of computers. (Tr. at 75:25-76:4.) The

pertinent claims include independent claim 19 and dependent claims 31 and 32, which state in

pertinent part:

19. A system for data protection, comprising a network representedlogically as a plurality of consistency groups, Gl, , Gn, each

consistency group representing:

the system further comprising a DPA manager operable to sendrequests to said DP As of G 1 , Gn,

31. The system of claim 19 wherein the D P A manager is one of theDPAs ofGl, , Gn.

32. The system of claim 19 wherein the DPA manager is a separateappliance from G l, , Gn,

The court finds that, while dependent claim31

requires that the DPA manager be oneof

the

DPAs within the identified consistency group, dependent claim 32 requires that the DPA

manager be a separate appliance from the DPAs contained in the identified consistency group.

In addition, the parties' agreed-upon construction for DPA states and appliance is a computer or

cluster of computers. (See Note 11, supra; D.I. 99 at 3 (defining a DPA as a computer or a

cluster o computers that serve as a data protection appliance, responsible for data protection

services ).) Therefore, the court construes DPA manager to mean a computer or a cluster

of computers that receives a cross-tag instruction, sends quiesce and tag commands, receives

confirmations, and sends un-quiesce commands.

determining success or failure of a consistent cross tag, which still requires that all DPA computers sendconformation notifications to the DPA manager. ('867 patent, 24:26-36.)

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Dated: September .i__ 2 4

2

emc corp. v. zerto, inc., c.a. no. 12-956-gms

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