United States District Court, District of Massachusetts
MEMORANDUM AND ORDER ON CLAIM CONSTRUCTION
Richard G. Stearns, UNITED STATES DISTRICT JUDGE.
In these three intellectual property cases, plaintiff Exergen Corporation accuses defendants Brooklands, Inc.; Kaz USA, Inc.; and Thermomedics, Inc. and Sanomedics International Holdings, Inc. (collectively the Sanomedics defendants) of infringing U.S. Patents Nos. 6, 292, 685 (the ’685 patent) and 7, 787, 923 (the ’923 patent). Before the court are the parties’ briefs on claim construction. The court heard argument, pursuant to Markman v. Westview Instruments, Inc., 517 U.S. 370 (1996), on August 13, 2014.
The ’685 and ’938 patents are both entitled “Temporal Artery Temperature Detector” and list Dr. Francesco Pompei as the inventor. The ’685 patent was issued on September 18, 2001, and the ’938 patent was issued on August 31, 2010. The ’938 patent is a continuation of the application that matured into the ’685 patent, and the two patents share virtually the same specification.
Both patents involve the measuring of a human being’s core, or deep body temperature. See ’685 patent, col. 1, lls. 19-20. Arteries, because they “receive blood directly from the heart,  are a good choice for detecting core temperature.” ’685 patent, col. 2, lls. 14-15. However,
an artery at the extremities of the body, such as those felt as pulse points at the wrist or ankle, are highly subject to vasoconstriction. This means, for example, that when an individual is extremely sick, in shock, or even just cold or nervous, the arteries constrict to reduce the flow of blood to that area as a means of retaining heat, or as in the case of shock, in an effort to redirect the blood to more critical areas of the body. This can result in a large temperature change at the artery which is a local artifact only and not representative of core temperature.
Id. col. 2, lls. 15-26.
The patents seize on the fact that the external branch of the temporal artery, which “travels in front of the ear and up into the soft temple area, terminating in a fork directly between the skin and the skull adjoining the eyebrow”, id. col.2, lls. 46-48, is “as short a distance from the heart as possible, with a high and relatively constant blood flow, and  is readily accessible on all individuals”; it therefore provides a reliable source for core temperature measurement. Id. col. 2, lls. 29-32. The patents disclose methods and apparatuses for detecting the temperature at the forehead over the temporal artery, and for computing an internal body temperature based on “a weighted difference of surface temperature and ambient temperature with a weighting coefficient h/pc.” Id. col. 3, lls. 14-16. Claims 1 and 14 of the ’685 patent and claims 39 and 54 of the ’938 patent are representative:
1 (’685 patent). A method of detecting human body temperature comprising:
laterally scanning a temperature detector across a forehead; and providing a peak temperature reading from plural readings during the step of scanning.
14 (’685 patent). A method of detecting human body temperature comprising:
detecting temperature at a forehead through a lateral scan across the temporal artery; and
computing an internal body temperature of the body as a function of ambient temperature and sensed surface temperature.
39 (’938 patent). A body temperature detector comprising:
a radiation detector; electronics that measure radiation from at least three readings per second of the radiation detector as target skin surface over an artery is viewed and that process the detected radiation to provide a body temperature approximation based on heat flow from an internal body temperature to ambient.
54 (’938 patent). A method of detecting human body temperature comprising:
measuring radiation as target skin surface of the forehead is viewed, and
processing the measured radiation to provide a body temperature approximation based on heat flow from an internal body temperature to ambient temperature.
Claim construction is in most instances a question of law for determination by the court. See Markman, 517 U.S. at 388-389. Claim terms are generally given their ordinary and customary meaning 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, 1312-1313 (Fed. Cir. 2005) (en banc) (citations omitted). “The person of ordinary skill in the art is deemed to read the claim term . . . in the context of the entire patent, including the specification.” Id. at 1313.
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.” Id. at 1315, quoting Vitronics Corp. v. Conceptronic, Inc., 90 F.3d 1576, 1582 (Fed. Cir. 1996). Because the purpose of the specification is to “teach and enable those of skill in the art to make and use the invention and to provide the best mode for doing so, ” Phillips, 415 F.3d at 1323, it is “entirely appropriate for a court, when conducting claim construction, to rely heavily on the written description for guidance as to the meaning of the claims.” Id. at 1317.
In addition to the patent’s specification, although “it often lacks the clarity of the specification and thus is less useful for claim construction purposes, ” the 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. Although not as reliable as the patent and its prosecution history, the court may also consider extrinsic evidence “if the court deems it helpful in determining the true meaning of language used in the patent claims.” Id. at 1318. Ultimately, “[t]he construction that stays true to the claim language and most naturally aligns with the patent’s description of the invention [in the specification] will be, in the end, the correct construction.” Id. at 1316.
To ease the burden on the court of construing the number of claims at issue, the parties have grouped the disputed terms under six broad categories, which the court will adopt.
Group I – Temperature and Measuring Terms
’938 patent – “measuring temperature of a region of skin of the forehead” & “measuring radiation as target skin surface of the forehead is viewed” The terms “measuring temperature of a region of skin of the forehead, ” and “measuring radiation as target skin surface of the forehead is viewed, ” appear in claims 51 and 54 of the ’938 patent. Claim 54 is recited supra.
51 (’938 patent). A method of detecting human body temperature comprising:
measuring temperature of a region of skin of the forehead; and
processing the measured temperature to provide a body temperature approximation based on heat flow from an internal body temperature to ambient temperature.
(Emphasis added to indicate disputed claim term).
Exergen proposes that these terms be given their ordinary and customary meanings, consistent with the wording of the claim. Brooklands and the Sanomedics defendants propose that both terms be construed to mean “scanning across the surface of the skin over the temporal artery to detect the peak temperature reading from a plurality of surface temperature readings.” Defendants’ reading is based on the argument that Exergen, in statements that it made in the patent specifications and prosecution history, disavowed the scope of “forehead, ” save for the skin over the temporal artery, and disavowed the scope of “measuring, ” other than scanning to detect the peak temperature from a plurality of temperature readings.
Claim scope is disavowed “[w]here the specification [or prosecution history] makes clear that the invention does not include a particular feature [such that] that feature is deemed to be outside the reach of the claims of the patent, even though the language of the claims, read without reference to the specification, might be considered broad enough to encompass the feature in question.” SciMed Life Sys., Inc. v. Advanced Cardiovascular Sys., Inc., 242 F.3d 1337, 1341 (Fed. Cir. 2001). The standard for finding disavowal of claim scope is “exacting.” Thorner v. Sony Computer Entm’t Am. LLC, 669 F.3d 1362, 1366 (Fed. Cir. 2012). Patentees may demonstrate an “intent to deviate from the ordinary and accustomed meaning of a claim term by including in the specification expressions of manifest exclusion or restriction, representing a clear disavowal of claim scope.” Teleflex, Inc. v. Ficosa N. Am. Corp., 299 F.3d 1313, 1325 (Fed. Cir. 2002) (emphasis added); see also Home Diagnostics, Inc. v. Life Scan, Inc., 381 F.3d 1352, 1358 (Fed. Cir. 2004) (“Absent a clear disavowal in the specification or the prosecution history, the patentee is entitled to the full scope of its claim language.”) (Emphasis added).
Defendants contend that Exergen’s claim scope disavowal is clear and unambiguous. The argument is based on the following disclosures. With respect to “forehead, ” the Abstract of the patents states that “[b]ody temperature measurements are obtained by scanning a thermal radiation sensor across the side of the forehead over the temporal artery.” (Emphasis added). The first sentence of the Summary of the Invention characterizes “[t]he present invention” as “provid[ing] for particularly convenient temperature readings of neonate, child and adult temperatures by detecting the temperature of the forehead directly over the superficial temporal artery.” ’938 patent, col. 2, lls. 20-23 (emphasis added). See Verizon Servs. Corp. v. Vonage Holdings Corp., 503 F.3d 1295, 1308 (Fed. Cir. 2007) (“When a patent thus describes the features of the ‘present invention’ as a whole, this description limits the scope of the invention.”). Likewise, Figure 1 is described as “illustrat[ing] an infrared thermometer scanning the temporal artery in the forehead in accordance with the present invention.” Id. col. 3, lls. 55-58 (emphasis added).
The specification extols the particular benefits of the temporal artery as a site providing core temperature measurements of an accuracy superior to that of other possible sites. See ’938 patent, col. 2, lls. 25-35 (arteries at the extremities are subject to vasoconstriction and therefore variable temperatures); id. col. 2, lls. 48-51 (the carotids, although directly extending from the aorta, are at best “partially embedded” and “not accessible at the skin”). In contrast,
[d]emonstrably, the temporal artery is very easily accessible; in fact in most individuals, it is usually quite visible. Terminating in a two-prong fork, it easily doubles the assurance of measuring the correct area. Touching it does not present a risk of injury. There are no mucous membranes present, thus eliminating the risk of contaminates such as those found in the mouth and rectum. And, despite lying so close to the skin surface, the temporal artery perfusion, which is the flow of blood per unit volume of tissue, remains relatively constant and so ensures the stability of blood flow required for our measurement.
Id. col. 2, lls. 57-67.
Similarly, during the prosecution of the asserted patents and those in the same family sharing the same specification, Exergen promoted the invention’s ability to capitalize on aspects of the temporal artery that make it particularly sensitive to temperature measurement. See, e.g., ’938 patent prosecution history (PH), 3/19/2010 amendment at 17 (discussing asserted claims 51 and 54 and referring to Exergen’s Temporal Artery Thermometer – “[i]t was only after years of research that Applicant recognized that a certain ‘region of skin of the forehead’ may be used to obtain accurate internal body temperature.”); ’685 patent PH, 8/2/2000 Amendment at 8 (“ [T]he superficial temporal artery, illustrated in Figure 1, offset from the center of the forehead where contact forehead temperatures are typically made, provides an exceptionally reliable temperature reading. Once Mr. Pompei recognized the significance of superficial temporal artery measurement, he had to devise a device and method by which an untrained individual could reliably obtain that temperature reading despite the unreliable surrounding temperatures of the forehead.”); United States Patent Application No. 09/923, 240 (the ’240 application) PH, 5/29/2003 Amendment at 2 (“Walsall et al. has been cited for measurement of the forehead. However, forehead measurements are typically taken at the center of the forehead and there is no suggestion in Walsall of taking a measurement to the side of the forehead over the temporal artery.”).
With respect to “measuring, ” the Abstract discloses that “[b]ody temperature measurements are obtained by scanning a thermal radiation sensor across the side of the forehead over the temporal artery. A peak temperature measurement is processed to compute an internal temperature of the body . . . .” (Emphasis added). Figure 1 is described as “scanning the temporal artery.” (Emphasis added). ’938 patent, col. 3, lls. 56-57. Scanning and peak detection is also the disclosed method for locating the temporal artery. “To locate the temporal artery, a temperature detector, preferably a radiation detector , is scanned across the side of the  forehead over the temporal artery while electronics in the detector search for the peak reading which indicates the temporal artery.” Id. col. 4, lls. 18-22. The specification distinguishes prior art detectors on the basis of the scan feature. Id. col. 8, l. 66-col. 9, l. 2 (“However, none of those designs provide the unique combination of elements which enable consistent measurements of core temperature by scanning across a superficial artery.”) (Emphasis added).
Likewise, the prosecution history emphasizes the inventiveness of scanning and peak detection. See, e.g., ’938 patent PH, 3/19/2010 Amendment at 13 (“Seacord does not teach or suggest ‘moving a radiation detector to scan skin over an artery and measure radiation emitted from the skin over the artery.’ ”); ’685 patent PH, 4/12/01 Amendment at 6 (“In the context of the present disclosure, peak temperature reading is to indicate the temperature of the temporal artery across which the detector is scanned.”).
With this sampling of defendants’ evidence in mind, the court will turn first to the prosecution history, heeding the caution that
while the prosecution history can inform whether the inventor limited the claim scope in the course of prosecution, it often produces ambiguities created by ongoing negotiations between the inventor and the PTO. Abbott Labs. v. Sandoz, Inc., 566 F.3d 1282, 1289 (Fed. Cir. 2009). Therefore, the doctrine of prosecution disclaimer only applies to unambiguous disavowals. Id.
Grober v. Mako Prods., Inc., 686 F.3d 1335, 1341 (Fed. Cir. 2012), reh’g denied (Sept. 14, 2012). When viewed in the context of the “ongoing negotiations between the inventor and the PTO, ” the prosecution history establishes no unambiguous disavowal. The referenced discussion of “a certain region of the forehead” in the ’978 patent prosecution history occurred while Exergen sought to distinguish its prior art patents directed to tympanic temperature thermometers. See ’978 patent PH, 3/19/2010 Amendment at 17. Because the prior art involved another body site, there was no imperative for Exergen to cede the claim scope of “forehead” to overcome this prior art. Although Exergen touted the desirability of the temporal artery for temperature measurement over the forehead generally,
[m]ere criticism of a particular embodiment encompassed in the plain meaning of a claim term is not sufficient to rise to the level of clear disavowal. Epistar Corp. v. Int’l Trade Comm’n, 566 F.3d 1321, 1335 (Fed. Cir. 2009) (holding that even a direct criticism of a particular technique did not rise to the level of clear disavowal). In Spine Solutions, Inc. v. Medtronic Sofamor Danek USA, Inc., [620 F.3d 1305, 1315 (Fed. Cir. 2010), ] we explained that even where a particular structure makes it “particularly difficult” to obtain certain benefits of the claimed invention, this does not rise to the level of disavowal of the structure.
Thorner, 669 F.3d at 1366. Similarly, the cited ’685 prosecution statements were made in the context of overcoming an obviousness rejection based on a combination of several prior art references. See ’685 patent PH, 8/2/2000 Amendment at 7-8. In these statements, Exergen did not unambiguously cede the scope of “forehead, ” other than to observe that “exten[ding] the peak detection technique from a tympanic membrane measurement to a temporal artery measurement would not have been obvious.” Id. at 8. Exergen also similarly distinguished Walsall in the context of a (non)obviousness analysis. See ’240 application, 5/29/2003 Amendment at 3 (“[N]none of the references [including Walsall] teach a body temperature detector which is programmed to provide a temperature display based on a model of heat balance relative to arterial temperature as a temperature detector is scanned across an artery.”).
The “measuring” prosecution history statements, on close examination, also do not unambiguously reflect an intent to disavow claim scope. Although Exergen distinguished Seacord on the basis of scanning, “Seacord merely describes an ear thermometer that is inserted into the ear to measure the infrared radiation emitted by the tympanic membrane.” ’938 patent PH, 3/19/2010 Amendment at 12. Scanning, in other words, is not the only distinction between the relevant claims and Seacord. The scanning and peak detection discussion of the ’685 patent prosecution history occurred in the context of overcoming anticipation rejections for claims 1 and 2, see ’685 patent PH, 4/12/2001 Amendment at 5-6, which explicitly recite scanning and peak detecting elements, see ’685 patent, claims 1-2, and thus do not restrict other claims based on the same specification.
The cited statements in the specification also fall short of an unambiguous disavowal. The specification, by its own terms, contemplates measuring the forehead generally, even though the temporal artery is the preferred region for measuring purposes. See ’938 patent, col. 3, lls. 1-3 (“In accordance with one aspect of the invention, a temperature sensor is scanned across the forehead, preferably in the vicinity of the temporal artery.”). With respect to scanning and peak detection, although it is a feature that distinguishes the claimed invention from prior art, it is not the only such feature. See id., col. 9, lls. 2-7 (“Specifically, the Exergen D501 Industrial Temperature Detector used in [sic] emissivity compensating cup and provided a ...