MEMORANDUM OPINION

LEONARD P. STARK, District Judge.

I. INTRODUCTION

Plaintiff Enova Technology Corporation ("Plaintiff" or "Enova") filed suit against defendants Initio Corporation, Initio Corporation (California), Western Digital Corporation, Buffalo Inc., and Buffalo Technology (USA), Inc.1 (collectively, "Defendants"), alleging infringement of U.S. Patent Nos. 7,136,995 ("the `995 patent"), entitled "Cryptographic Device," and 7,900,057 ("the `057 patent"), entitled "Cryptographic Serial ATA Apparatus and Method" (collectively, the "patents-in-suit").2 (See Docket Item ("D.I.") 1) Previously, there was a third patent-in-suit — U.S. Patent No. 7,386,734 — but, on December 3, 2012, the Court granted the parties' requests to dismiss claims relating to this patent. (D.I. 359; D.I. 360)

The Court held a Markman hearing on December 13, 2011. (See Markman Hr'g Tr., Dec. 13, 2011 (D.I. 190) (hereinafter "Tr.")) The Court now construes the disputed claims in the two patents for which infringement claims remain pending.3

II. LEGAL STANDARDS

"It is a bedrock principle of patent law that the claims of a patent define the invention to which the patentee is entitled the right to exclude." Phillips v. AWH Corp., 415 F.3d 1303, 1312 (Fed. Cir. 2005) (internal quotation marks omitted). Construing the claims of a patent presents a question of law. See Markman v. Westview Instruments, Inc., 52 F.3d 967, 977-78 (Fed. Cir. 1995), aff'd, 517 U.S. 370, 388-90 (1996). "[T]here is no magic formula or catechism for conducting claim construction." Phillips, 415 F.3d at 1324. Instead, the court is free to attach the appropriate weight to appropriate sources "in light of the statutes and policies that inform patent law." Id.

"[T]he words of a claim are generally given their ordinary and customary meaning ... [which 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, i.e., as of the effective filing date of the patent application." Id. at 1312-13 (internal citations and quotation marks omitted). "[T]he ordinary meaning of a claim term is its meaning to the ordinary artisan after reading the entire patent." Id. at 1321 (internal quotation marks omitted). The patent specification "is always highly relevant to the claim construction analysis. Usually, it is dispositive; it is the single best guide to the meaning of a disputed term." Vitronics Corp. v. Conceptronic, Inc., 90 F.3d 1576, 1582 (Fed. Cir. 1996).

While "the claims themselves provide substantial guidance as to the meaning of particular claim terms," the context of the surrounding words of the claim also must be considered. Phillips, 415 F.3d at 1314. Furthermore, "[o]ther claims of the patent in question, both asserted and unasserted, can also be valuable sources of enlightenment ... [b]ecause claim terms are normally used consistently throughout the patent...." Id. (internal citation omitted).

It is likewise true that "[d]ifferences among claims can also be a useful guide.... For example, the presence of a dependent claim that adds a particular limitation gives rise to a presumption that the limitation in question is not present in the independent claim." Id. at 1314-15 (internal citation omitted). This "presumption is especially strong when the limitation in dispute is the only meaningful difference between an independent and dependent claim, and one party is urging that the limitation in the dependent claim should be read into the independent claim." SunRace Roots Enter. Co., Ltd. v. SRAM Corp., 336 F.3d 1298, 1303 (Fed. Cir. 2003).

It is also possible 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, 415 F.3d at 1316. It bears emphasis that "[e]ven when the specification describes only a single embodiment, the claims of the patent 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." Liebel-Flarsheim Co. v. Medrad, Inc., 358 F.3d 898, 906 (Fed. Cir. 2004) (internal quotation marks omitted), aff'd, 481 F.3d 1371 (Fed. Cir. 2007).

In addition to the specification, a court "should also consider the patent's prosecution history, if it is in evidence." Markman, 52 F.3d at 980. The prosecution history, which is "intrinsic evidence," "consists of the complete record of the proceedings before the PTO [Patent and Trademark Office] and includes the prior art cited during the examination of the patent." Phillips, 415 F.3d at 1317. "[T]he prosecution history can often inform the meaning of the claim language by demonstrating how the inventor understood the invention and whether the inventor limited the invention in the course of prosecution, making the claim scope narrower than it would otherwise be." Id.

A court also may rely on "extrinsic evidence," which "consists of all evidence external to the patent and prosecution history, including expert and inventor testimony, dictionaries, and learned treatises." Markman, 52 F.3d at 980. For instance, technical dictionaries can assist the court in determining the meaning of a term to those of skill in the relevant art because such dictionaries "endeavor to collect the accepted meanings of terms used in various fields of science and technology." Phillips, 415 F.3d at 1318. In addition, expert testimony can be useful "to ensure that the court's understanding of the technical aspects of the patent is consistent with that of a person of ordinary skill in the art, or to establish that a particular term in the patent or the prior art has a particular meaning in the pertinent field." Id. Nonetheless, courts must not lose sight of the fact that "expert reports and testimony [are] generated at the time of and for the purpose of litigation and thus can suffer from bias that is not present in intrinsic evidence." Id. Overall, while extrinsic evidence "may be useful" to the court, it is "less reliable" than intrinsic evidence, and its consideration "is unlikely to result in a reliable interpretation of patent claim scope unless considered in the context of the intrinsic evidence." Id. at 1318-19.

Finally, "[t]he construction that stays true to the claim language and most naturally aligns with the patent's description of the invention will be, in the end, the correct construction." Renishaw PLC v. Marposs Societa' Per Azioni, 158 F.3d 1243, 1250 (Fed. Cir. 1998). It follows that "a claim interpretation that would exclude the inventor's device is rarely the correct interpretation." Osram GmbH v. Int'l Trade Comm'n, 505 F.3d 1351, 1358 (Fed. Cir. 2007).

III. CONSTRUCTION OF DISPUTED TERMS

The Court will adopt Plaintiff's construction. As Plaintiff explains, "[t]o encrypt a set of data, one applies an encryption algorithm, or cipher algorithm, to the data, or text, which turns it into cipher text, unreadable to anyone without the key to decrypt it." (D.I. 129 at 8; see also `995 patent col.5 ll.6-23 ("Cipher engine 436 is ... programmed to transparently encrypt/decrypt streaming data.... Cipher engine 436 may include a 64-bit, 128-bit, or other data width interface depending on the ciphering algorithm being used."))

The Court does not find support for Defendants' suggestion that encryption must always "prevent" unauthorized access.5 Even if this is the intended purpose of the invention, the Court is not persuaded that this purpose needs to be incorporated into the construction of the claim term "encrypted." Nor is it clear precisely what Defendants mean by their proposed "change the form of the data" language.

Again, the Court will adopt Plaintiff's proposed construction. The specification provides:

(`995 patent col.4 ll.55-58) The parties' dispute is whether data in the third of these categories — "passed through unmodified" data — can undergo any modification at all (such as may occur with a protocol translator, given that a data generator and a data storage device may be "speaking different languages"). (See, e.g., D.I. 137 at 10-11; Tr. at 73-75) The Court is not persuaded by Defendants' proposal that such data must be forwarded without any transformation whatsoever. Instead, "passed through" as used in the patent claims means simply that the data is not encrypted nor decrypted.

For their proposed construction, Defendants rely primarily on their contention that there was a prosecution history disclaimer. (See Tr. at 66; D.I. 131 at 10-12; D.I. 139 at 5) The Court does not agree. Defendants have failed to meet their heavy burden of showing a "clear and unmistakable" disavowal. Omega Eng'g, Inc. v. Raytek Corp., 334 F.3d 1314, 1325-26 (Fed. Cir. 2003). Moreover, as Plaintiff points out, the specification discloses an embodiment in which the patented cryptographic device "may be integrated in ASIC chip form" (`995 patent col.4 ll.6-7); an "ASIC" (i.e., an "Application Specific Integrated Circuit") is a "single integrated chip customized for a particular use." (D.I. 138, Warm Decl. ¶ 2; see also D.I. 137 at 9) Defendants' construction would limit the claims to such a single, integrated "unit," which is unwarranted given the permissive "may" language in the specification and the broad "a data stream interceptor" language of the claims. See generally KCJ Corp. v. Kinetic Concepts, Inc., 223 F.3d 1351, 1356 (Fed. Cir. 2000) (stating "a" usually means "one or more" in patent claims).

The Court's decision to adopt the Plaintiff's proposed construction for this term follows from its earlier decisions to adopt Plaintiff's proposed constructions of the other disputed terms.6 Additionally, Plaintiff's proposed construction is more consistent with the patent's teaching that the data generating device and the data storage device may "speak different languages," provided there is a protocol translator assisting them.

The parties disagree as to whether this disputed term, appearing in the preamble of claim 1, is a limitation of the claim. The Court agrees with Plaintiff that it is not. Therefore, this term does not require construction.

Generally a preamble does not limit the claims. See Allen Eng'g Corp. v. Bartell Indus., Inc., 299 F.3d 1336, 1346 (Fed. Cir. 2002). However, language in a preamble is construed as limiting "if it recites essential structure or steps, or if it is necessary to give life, meaning, and vitality to the claim." Catalina Mktg. Int'l, Inc. v. Coolsavings.com, Inc., 289 F.3d 801, 808 (Fed. Cir. 2002) (internal quotation marks omitted). Consistent with Catalina, a preamble term is limiting if it: (1) provides antecedent basis for a claim term, (2) is essential to help understand the claim terms, (3) provides any additional steps or structure that is underscored as important by the specification, or (4) was relied on during prosecution. See id.

Defendants' contention that construing this claim term in the manner they propose would breath life into claims 13-15 is unpersuasive. (See D.I. 139 at 2 n.1) Defendants' primary contention is that there cannot be a protocol translator inside the device. (See Tr. at 92-100) But Defendants have not persuaded the Court that a device containing a protocol translator is excluded from the scope of the claims.

The Court agrees with Plaintiff that "non-SATA host embodiments are disclosed in the specification." (Tr. at 35; see also D.I. 137 at 2-3; `057 patent col.8 l.66 - col. 9 l.3)7 The Court finds no basis to adopt Defendants' construction, which would narrow the "host" in the claims to only SATA hosts.

Defendants' proposal is supported by neither the specification nor the claim language. Claim 6 provides: "The cryptographic SATA apparatus of claim 1, wherein said SATA protocol stack is operatively coupled to a USB (Universal Serial Bus) interface via a SATA-to-USB protocol translator." (`057 patent, claim 6, col.13 ll.40-43) Claim 6 depends from claim 1, which describes the SATA protocol stack as a "SATA protocol stack for communicating with an interface of a device." (Id. at claim 1, col.13 ll.8-9) Further, the specification states, for example:

(Id. at col.8 l.64 - col.9 l.3) As Plaintiff observes, such a disclosure "clearly demonstrates to one of skill in the art that the invention encompasses embodiments where one side of the invention uses a SATA protocol and the other side uses another protocol, with given examples of parallel ATA and USB." (D.I. 137 at 14)

IV. CONCLUSION

For the reasons given above, the Court will construe the terms of the patents-in-suit consistent with this Memorandum Opinion. An appropriate Order will be entered.