United States District Court, N.D. Illinois, Eastern Division
MEMORANDUM OPINION AND ORDER
JOHN Z. LEE, District Judge.
Cleversafe, Inc. ("Cleversafe") has sued Amplidata, Inc. ("Amplidata") alleging infringement of three patents: U.S. Patent Nos. 7, 953, 771 ("the '771 patent"), 7, 953, 937 ("the '937 patent"), and 7, 546, 427 ("the '427 patent"). The case is before the Court for the construction of nine terms.
The three patents-in-suit relate to aspects of distributed data storage systems. (Def.'s Opening Claim Construction Br. 1 ("Def.'s Br.").) In such a system, data is stored across multiple "nodes" rather than a single location. ( Id. )
On September 30, 2005, Cleversafe filed U.S.App. No. 11/241, 555 disclosing a system and method for storing data on a distributed data storage system. ('937 Patent, at , Joint Appendix ("J.A.") 703.) The method separates data into "slices" or "subsets" that are less usable than the original data unless combined with other subsets. ( Id. at col.2 ll.54-60, J.A. 712.) The subsets are encoded using a coding algorithm, and the subsets and coded subsets are distributed over a network of storage nodes to increase security. ( Id. at col.2 ll.60-67, J.A. 712.) The information can be recreated by retrieving the subsets and coded subsets and applying a decoding algorithm. ( Id. at col.3 ll.1-6, J.A. 713.) The system is "computationally efficient compared to known systems." ( Id. at col.3 ll.6-11, J.A. 713.) On May 31, 2011, the application issued as U.S. Patent No. 7, 953, 937. ( Id. at , , J.A. 703.)
On April 13, 2006, Cleversafe filed U.S.App. No. 11/403, 391 as a continuation in part of U.S.App. No. 11/241, 555. ('427 Patent at , J.A. 1.). This application disclosed a system and method for rebuilding data previously stored on a distributed data storage network when one or more nodes becomes unavailable by applying an algorithm to the available data slices. ( Id. at col.3 ll.16-29, J.A. 21.) On June 9, 2009, the application issued as U.S. Patent No. 7, 546, 427. ( Id. at , , J.A. 1.)
On December 8, 2009, Cleversafe filed U.S.App. No. 12/633, 779. ('771 Patent at , J.A. 562.) This application disclosed a distributed data storage network in which virtual "vaults" organize and control access to data. ( Id. at , J.A. 562.) On May 31, 2011, the application issued as U.S. Patent No. 7, 953, 771. ( Id. at , , J.A. 562.)
The following terms are in dispute: (1) data slice and plurality of data slices; (2) virtual digital data storage vault; (3) encode, using a coding algorithm, a plurality of subsets of data to create a plurality of coded values; (4) information dispersal algorithm; (5) strings of data; (6) subsets of data; (7) list of unusable storage nodes; (8) the request is valid/the request is invalid; and (9) supports.
Claim construction is a question of law to be decided by a judge. Markman v. Westview Instruments, Inc., 517 U.S. 370, 391 (1996). The Court begins its analysis with the intrinsic evidence, which consists of the patent claims, specification, and prosecution history. Vitronics Corp. v. Conceptronic, Inc., 90 F.3d 1576, 1582 (Fed. Cir. 1996). Words "are generally given their ordinary and customary meaning." Id. "[T]he ordinary and customary meaning of a claim term is the meaning that the term would have to a person of ordinary skill in the art in question at the time of the invention...." Phillips v. AWH Corp., 415 F.3d 1303, 1313 (Fed. Cir. 2005).
Terms are given "the meaning and scope with which they are used in the specification and the prosecution history." Kinik Co. v. ITC, 362 F.3d 1359, 1365 (Fed. Cir. 2004). The specification is usually "dispositive; it is the single best guide to the meaning of a disputed term." Vitronics, 90 F.3d at 1582. However, a particular embodiment used in the specification to aid understanding should not import limitations into the claim. Superglide Corp. v. DirecTV Enters., Inc., 358 F.3d 870, 875 (Fed. Cir. 2004). Nonetheless, a claim may be limited to its preferred embodiment if permitting expansive claim language would undermine the public notice requirements of 35 U.S.C. § 112. LizardTech, Inc. v. Earth Resource Mapping, Inc., 424 F.3d 1336, 1346 (Fed. Cir. 2005).
The prosecution history may serve to further "exclude any interpretation that was disclaimed during prosecution." Chimie v. PPG Indus., Inc., 402 F.3d 1371, 1384 (Fed. Cir. 2005). However, a claim may not be narrowed "simply by pointing to the preferred embodiment or other structures or steps disclosed in the specification or prosecution history." CCS Fitness, Inc. v. Brunswick Corp., 288 F.3d 1359, 1366 (Fed. Cir. 2002).
Extrinsic evidence, such as dictionaries and expert testimony, may be used only if the intrinsic evidence alone is insufficient to determine the meaning of the claim terms. Vitronics, 90 F.3d at 1583.
Finally, the doctrine of "claim differentiation" provides that "each claim in a patent is presumptively different in scope." RF Del., Inc. v. P. Keystone Techs., Inc., 326 F.3d 1255, 1263 (Fed. Cir. 2003). "That presumption is especially strong when the limitation in dispute is the only meaningful difference between an independent and dependent claim." Acumed LLC v. Stryker Corp., 483 F.3d 800, 806 (Fed. Cir. 2007). However, claim differentiation is a "rule of thumb" and not absolute. Edwards Lifesciences LLC v. Cook, Inc., 582 F.3d 1322, 1332 (Fed. Cir. 2009). The scope of a claim may be limited so as to create redundant claims if required by "the clear import of the specification, " id., or by the prosecution history. See Fantasy Sports Properties, Inc. v. Sportsline.com, Inc., 287 F.3d 1108, 1116 (Fed. Cir. 2002) (presumption of claim differentiation overcome by disclaimer during prosecution history).
I. "Data slice" and "plurality of data slices"
The parties dispute the meaning of the phrases "data slice" and "plurality of data slices" used in claims 1, 2, 4, 5, 7, 9, 10, 12, and 13 of the '937 patent and claims 3 through 7 of the '427 patent. (Pl.'s Resp. Claim Construction Br. 9 n.6 ("Pl.'s Br.").) Amplidata argues that a plurality of data slices is "a plurality of data structures each consisting of a data subset and a corresponding coded data subset." (Def.'s Br. 4.) Cleversafe proposes an alternative construction of "a collection of subsets of data and coded values." (Pl.'s Br. 9.) The disagreement lies in whether a data slice must contain both at least one data subset and at least one coded value and, if so, whether the data subset(s) and coded value(s) must correspond with one another.
As to the first question, on October 7, 2009, Cleversafe significantly amended the application that would eventually become the '937 patent. In its remarks accompanying the amendments, Cleversafe distinguished what would become claim 1 of the '937 patent from the prior art, Moulton, stating:
Moulton does not teach or suggest creating n data slices from n subsets of data and n coded values. Moulton also does not teach or suggest outputting the data subsets and the code values as a single data element (e.g., a data slice), but does teach that the data units may be separately stored from the parity value or that only the parity values be stored.
(J.A. 1030.) The quoted passage supports the construction that a data slice must contain at least one data subset and at least one coded value. What is more, once the term "data slice" is construed to contain at least one data subset and at least one coded value, the statement " n data slices from n subsets of data and n coded values" leads to the conclusion that a 1:1:1 ratio must exist between a data slice, a data subset, and a coded value.
Such a construction is entirely consistent with the patent's specification. For example, the "Summary of the Invention" portion of the specification describes a process by which a digital data storage system slices "the original data into data subsets, " after which a "coding algorithm uses the subsets to create coded data subsets." ('937 Patent at c.2 ll.54-60.) Once the data subsets and their coded data subsets are created, "[e]ach data subset and its corresponding coded subset may be transmitted separately across a communications network and/or stored in separate storage nodes." ( Id. at c.2 ll.64-67.) In this context, the word "each" can only modify a combination of a data subset and a coded data subset, which combinations are separately transmitted across the network. Otherwise, to read the sentence to mean "each data subset" and "each coded data subset" would render the word "separately" superfluous. See Callicrate v. Wadsworth Mfg., Inc., 427 F.3d 1361, 1369 (Fed. Cir. 2005) (court's construction must fully reflect the language in the patent).
Furthermore, although Cleversafe would have "data slices" mean "subsets of data, coded values, or both, " such a construction is not only inconsistent with the prosecution history and the specification as discussed above, but the patent itself teaches a system that, among other things, creates "a plurality of data slices from a plurality of subsets of data and the plurality of coded values." ('937 Patent at c.9 ll.23-24.) In other words, to create data slices, one needs both data subsets and coded values. If the patent contemplated that a plurality of data slices could be created from a plurality of subsets of data and/or the plurality of coded values, it certainly could have stated so.
For its part, Cleversafe also argues that the doctrine of claim differentiation requires a broader reading of the term "data slice." (Pl.'s Br. 9-10.) Claim 3 of the '427 patent is an independent claim, while claim 4 depends on claim 3. Claim 4 provides: "The method of claim 3, wherein each data slice comprises a data subset and a coded data subset." ('427 Patent col.16 ll.29-29, J.A. 27.) Thus, according to Cleversafe, the doctrine of claim differentiation dictates that the term "data slice" must be broader than something that "comprises a data subset and a coded data subset." Claim differentiation, however, is not an insurmountable doctrine, but a presumption that can be overcome. See Fantasy Sports, 287 F.3d at 1115. Here, the clear and unambiguous statements made by Cleversafe during the prosecution history, coupled with the statements in the patent's specification, are sufficient to overcome that presumption. See id. at 1116.
The remaining question is whether the data subset and coded value that are contained in a data slice must correspond with one another. In arguing the affirmative, Amplidata points to several instances in the '937 and '427 patents in which data subsets are paired with their corresponding coded subsets. For example, Amplidata cites Figure 4 of the '937 patent, which shows data subsets A, B, and E paired with "their corresponding coded values" cA, cB, and cE. (Def.'s Br. 5.) However, the exemplary ...