Full opinion text
OPINION AND ORDER SCHEINDLIN, District Judge. I. INTRODUCTION Medinol Ltd. (“Medinol”) brings this action for damages and declaratory and permanent injunctive relief relating to the alleged infringement by Guidant Corp. and its subsidiary Advanced Cardiovascular Systems, Inc. (“ACS”) (collectively “Guidant”) of certain of Medinol’s patents. This Opinion resolves Guidant’s motion for summary judgment on the issue of invalidity, which asserts that all claims of the patents-in-suit are obvious as a matter of law. For the following reasons, Guidant’s motion for summary judgment on invalidity is denied. II. BACKGROUND Two previous Opinions have been issued in this case. One granted in part and denied in part Guidant’s motion for summary judgment based on collateral estoppel. The other construed several terms necessary to evaluate the claims in this case. Familiarity with both Opinions is assumed. A. The Parties Medinol, which has its principal place of business in Tel Aviv, Israel, designs and manufactures coronary stents. The company was founded by, among others, Dr. Jacob (“Kobi”) Richter, who currently serves as Medinol’s Chairman of the Board and Chief Technical Officer. Guidant develops, markets, and sells cardiovascular medical products and has its principal place of business in Indiana. ACS has its principal place of business in California. B. The Technology The devices at issue in this litigation are directed toward opening diseased coronary arteries and maintaining blood flow to and from the heart. In the 1970’s, the preferred treatment for coronary artery disease was “balloon angioplasty,” also known as “percutaneous transluminal coronary angioplasty”, or PTCA. This procedure involves first inserting a balloon into the diseased artery via a catheter, then inflating the balloon to push open the artery. The goal is for the artery to stay open once the balloon is removed. However, in about thirty-five percent of such procedures, the effects were temporary and the artery eventually re-closed, or “recoiled.” Stents provide a more permanent solution. A stent is a “medical device much like [ ] miniature scaffolding that physically holds open a diseased artery into which [it is] inserted.” Stents are used to treat diseased arteries in the heart (i.e. coronary arteries), as well as “peripheral arteries” located in other areas of the body. Stents are introduced into the blood vessel on a balloon catheter, in a procedure during which the catheter is maneuvered into the blocked artery, where the balloon is inflated, causing the stent to expand against the vessel wall. Once the balloon has been deflated and removed, the stent remains in place indefinitely, holding the blood vessel open and thereby improving blood flow. The modern stent originated in the 1980s. In April 1988, a patent was issued to Julio Palmaz (Palmaz ’762 Patent) for an “expandable intraluminal graft, and method and apparatus for implanting an expandable intraluminal graft,” i.e., a “stent,” which Johnson & Johnson commercialized in 1991. The Palmaz ’762 Patent described the first stent to “include a plurality of closed cells” that, upon expansion, “transformed [from slot-shaped cells] into diamond-shaped cells, resulting in an expanded stent with a honeycomb appearance.” At approximately the same time, Palmaz patented another stent (Palmaz ’417 Patent) “combining slot-shaped cells with flexible connectors to increase longitudinal flexibility.” Other designs used “coil connectors” to impart great flexibility, but at the expense of radial strength once the stent is expanded or deployed. In 1995, Richard Schatz developed a new variation of the Palmaz stent, involving “straight flexible connectors between tube sections” (Palmaz/Schatz ’984 Patent). C. Prior Stent Designs Three prior stent designs are particularly important to resolution of this motion. First, in the early 1990s, Guidant developed a stent design based on connecting single serpentine rings with flexible straight connectors, for which it obtained the Lau ’955 Patent. Second, in 1994, a team of engineers filed, and then abandoned, a patent application for a “hybrid stent” that attempted to combine flexibility and radial strength (“the Burmeister Application”). Third, in 1999, the Fischell ’370 Patent was issued, disclosing a stent using rings that become circular when fully expanded, connected with either straight or “undulating” (looped) longitudinals. 1. Lau The Lau ’955 Patent asserts that “[w]hat has been needed and heretofore unavailable is a stent which has a high degree of flexibility so that it can be advanced through tortuous passageways and can be readily expanded and yet have the mechanical strength to hold open the body lumen into which it is expanded. The present invention satisfies this need.” Lau’s invention was summarized as “an expandable stent which is relatively flexible along its longitudinal axis to facilitate delivery through tortuous body lumens, but which is stiff and stable enough radially in an expanded condition to maintain the patency of a body lumen such as an artery when implanted therein.” The Lau ’955 Patent discloses an invention comprising serpentine rings, connected with straight “connectors,” or links between rings. The rings may be connected in two ways: out-of-phase (connecting adjacent crowns of rings that face each other) and in-phase (crowns pointing in one direction). The out-of-phase design, shown in Lau Figure 11, contains only a single connector between each pair of rings. While the straight connectors are designed to be inflexible, serving to “provide increased stability and ... prevent warping of the stent upon expansion,” the rings themselves permit flexibility. Moreover, Lau teaches that “[t]he number and location of elements interconnecting adjacent cylindrical elements can be varied in order to develop the desired longitudinal flexibility in the stent structure both in the unexpanded as well as the expanded condition.” 2. Burmeister Beginning in 1994, Scimed engineers, including Burmeister, Euteneuer and Brown, sought to develop a hybrid stent that would partially self-expand, and then fully expand with a balloon. A patent application to this effect, including several drawings, was filed with the U.S. Patent and Trademark Office (“PTO”) on May 19, 1994. The application asserts that: [t]he devices of this invention are generally cylindrical or tubular in overall shape and of such a configuration as to allow radial expansion for enlargement. Furthermore, the devices are comprised of at least one component which exhibits a resiliency or spring-like tendency to self-expand the device and at least one other component which is deformable so as to allow an external force, such as a balloon positioned within the body of the device, to further expand it to a final desired size. Most relevant to this motion are Figures 14a and 14b of the Burmeister Application, created by Euteneuer and Brown. Figure 14a discloses the Burmeister design in its unexpanded state, while Figure 14b reflects the expanded, or deployed, state. The team of engineers who produced the Burmeister design experimented with several different designs. The Burmeister design embodied in Figures 14a and 14b never entered the market; it was abandoned soon after the first stainless-steel prototypes were produced. 3. Fischell The Fischell Patent describes itself as “an expandable stent that can be used in an artery or any other vessel of the human body which, when expanded, forms a multiplicity of generally circular rings whose closed structure optimizes hoop strength so as to minimize elastic recoil of the vessel into which the stent is inserted.” “Although the optimum design for maximizing hoop strength is a closed circular structure, no prior art stent has been described which has a small diameter when percutaneously inserted into a vessel and which expands into the form of multiplicity of closed circular structures (i.e., rings) expanded outward against the vessel wall.” Fischell recites four objects, only two of which are relevant to this motion. First, “an object of this invention is to provide a stent having a maximum hoop strength by the employment of closed, generally circular structures which are in fact rings.” Second, “[sjtill another object of this invention is that the fully deployed rings are spaced apart by means of longitudinals which are either straight or undulating wires that are placed to be generally parallel to the longitudinal axis of the vessel into which the stent is deployed.” Notably, Dr. Timothy Fischell, an inventor of the ’370 patent, has testified that one of his goals was “to make a stent that would be very flexible.” D. The Patents-in-Suit According to Richter, prior art stents on the market in the last half of 1993 all possessed advantages and offsetting disadvantages, because they: were of two extreme kinds ..., [o]ne was very flexible ... but because it was very flexible, also when it was extended it was not stable. The loops could be drawn away from each other, and it would not support very well the lesion, the narrowing in the vessel. So, it could go anywhere you want [within the body], but would not support. The other type had a rigid enough, stable enough structure such that when deployed, it would support pretty well, but it was very inflexible, rigid. So you could not push it through the curves of the arterial system to the position you are trying to treat. That was suboptimal. The leading strong but inflexible stents were the Palmaz and Palmaz-Schatz. On the other end of the spectrum, coiled wire stents were very flexible, but at the expense of radial strength once deployed. Richter has stated that “the idea [that] brewed in my mind ... [was] that flexibility was needed when you are trying to track it through the curviness of the artery, [b]ut once you get it to the position you don’t need [flexibility.].” On September 12, 1995, U.S. Patent No. 5,449,373 was issued to Gregory Pinchasik et al. and assigned to Medinol. The application for this patent was filed on March 17, 1994. A series of stents, described as continuations or continuations-in-part of this patent, were invented by Henry Israel and Gregory Pinchasik, and assigned to Medinol. These patents — the ’303, ’018,-’120, ’381, and ’982 — describe a family of flexible, expandable stents. Specifically, Medinol’s patents: share the same drawings, and essentially the same specification, and are described as continuations of a series of applications beginning with Application Serial No. 282,181 ... filed on July 28, 1994, and continuations-in-part of Application Serial No. 213,272 ... which was filed on March 17, 1994, and issued as [the Pinchasik ’373 Patent]. The Medinol patents generally describe and illustrate stent designs that achieve the objectives and flexibility during delivery, compensation for foreshortening, continuous uniform scaffolding, and resistance to radial deformation and collapse upon expansion. Although Medinol originally alleged infringement of all five patents, “it has since dropped any claims relating to the ’303 and ’018 patents.” The remaining claims can be divided into roughly two groups: the “meander” claims and the “flexible cell” claims. The “meander” claims, comprised of the asserted claims of the ’120 and ’982 Patents, generally describe stent structures comprised of two types of meander patterns intertwined with one another. These patterns are referred to as “first meanders,” which extend in a circumferential direction; and “second meanders,” which extend in a longitudinal direction. I have construed “first meander” to mean “a periodic sinusoidal pattern about a center line.” I construed a “second meander” to mean “periodic pattern[s] about a center line oriented in a direction different from the axis of the first meanders.” A “flexible cell,” as used in the claims of the ’381 Patent, has been construed as “[a]n arrangement of structural elements that defines an enclosed space. The cells must be substantially flexible prior to expansion of the stent and substantially rigid after expansion of the stent.” Medinol introduced the NIR stent in 1996, based on the teachings of at least some of the patents-in-suit, although the record is unclear on this point. Between 1996 and 2000, Medinol sold over two million NIR stents. The NIR stent garnered notice from the industry as well. For example, Johnson & Johnson attempted to acquire the rights to the NIR stent in 1995, offering Medinol up to $335 million for the rights. The President of Johnson & Johnson asserted that the NIR stent “uniquely combines (1) flexibility (a serious disadvantage in the Palmaz/Palmaz-Schatz slotted tube design) and (2) radial strength (better than our current design).” E. The Cordis Litigation In December 1999, Medinol and its licensee, Scimed Life Systems, Inc. (“Scimed”), filed a patent infringement action in Delaware, alleging that Cordis Corp., Johnson & Johnson, and Johnson & Johnson Interventional Systems, Inc. had infringed certain claims of Medinol’s ’303, T20, and ’018 patents. After a two-week jury trial, the jury returned various verdicts of infringement, noninfringement and invalidity. Of most relevance to the present motion is that the Cordis jury found that all of the asserted claims were invalid for obviousness and failure to comply with the written description requirement, except for claim 13 of the ’120 Patent. Claim 13 is the only remaining claim common to the Cordis litigation and this case. The district court denied in part and granted in part Medinol and Scimed’s motion for judgment as a matter of law (“JMOL”) and for a new trial under Rule 59(a). Specifically, the court denied plaintiffs’ motion as to infringement, and also rejected plaintiffs’ argument that the asserted claims of the ’303 and ’018 patents are not invalid for obviousness, finding that “defendants presented substantial evidence to support a reasonable jury’s conclusion that claims 12, 35, 47 and 60 would have been obvious to one of ordinary skill in the art in July 1994, the time the inventions described in those claims were made.” In particular, the court rejected plaintiffs’ argument that they were entitled to a new trial based on an inconsistent jury verdict on obviousness: Claim 13 of the ’120 patent has an additional limitation, ie., that the stent must have “at least one of the loops of each of the first meanders disposed between each consecutive second meander to which the first meander is connected” over claim 60 of the ’018 patent. This supports the jury’s verdict that claim 13 is not invalid for obviousness whereas claim 60 is invalid. Medinol and Scimed then unsuccessfully appealed the denial of their post-trial motions to the Federal Circuit, which held that “there was substantial evidence in the record to support the conclusion that the asserted claims of the ’303 and ’018 patents were obvious over the prior art at the time they were filed with the PTO.” In response to plaintiffs’ argument that “even if each of the elements of the asserted claims was in the prior art, the record does not demonstrate that there was a motivation to combine” them, the Federal Circuit referred to the Burmeister Application as substantial evidence that “a person of ordinary skill in the art did, in fact, combine the elements of the stent design claimed by the ’303 and ’018 patents prior to July 28,1994.” The jury had before it expert testimony that a person of ordinary skill in the art, on July 28, 1994, would inspect the drawings of the Burmeister application and conclude it disclosed a stent design that combined the claimed elements of the balloon expandable stent design taught by the patents-in-suit. This was legally sufficient evidence from which the jury could have found a motivation to combine in the knowledge of one of ordinary skill in the art, a finding of fact we must presume the jury to have made given that it returned a verdict on the validity issue in favor of Cordis. III. LEGAL STANDARD A. Governing Law/Standard for Summary Judgment As a general principle, Federal Circuit precedent governs issues of patent law, while the law of the regional circuit applies to nonpatent issues. Summary judgment is appropriate if the record “show[s] that there is no genuine issue as to any material fact and that the moving party is entitled to judgment as a matter of law.” “An issue of fact is genuine ‘if the evidence is such that a jury could return a verdict for the nonmoving party.’ ” A fact is material when “it ‘might affect the outcome of the suit under the governing law.’ ” The movant has the burden of demonstrating that no genuine issue of material fact exists. In turn, to defeat a motion for summary judgment, the non-moving party must raise a genuine issue of material fact. To do so, it must do more than show that there is a “ ‘metaphysical doubt as to the material facts,’ ” and it “ ‘may not rely on conclusory allegations or unsubstantiated speculation.’ ” In determining whether a genuine issue of material fact exists, the court must construe the evidence in the light most favorable to the non-moving party and draw all justifiable inferences in that party’s favor. B. Standard of Review A patent enjoys a presumption of validity. A party seeking to destroy this presumption must do so with clear and convincing evidence of invalidity. Clear and convincing evidence exists when the movant “placefs] in the mind of the ultimate fact finder an abiding conviction that the truth of its factual contentions are ‘highly probable.’ ” C. Obviousness As an initial matter, “[t]he grant of summary judgment of invalidity for obviousness must be done on a claim by claim basis.” A claimed invention is unpatentable if the differences between it and the prior art “are such that the subject matter as a whole would have been obvious at the time the invention was made to a person having ordinary skill in the art.” The ultimate determination of obviousness is a legal conclusion based on the following underlying factual inquiries: (1) the scope and content of the prior art; (2) the level of ordinary skill in the prior art; (3) the differences between the claimed invention and the prior art; and (4) objective evidence of non-obviousness. Additionally, “[a] showing of obviousness requires a motivation or suggestion to combine or modify prior art references, coupled with a reasonable expectation of success.” 1. Scope and Content of Prior Art The scope of the prior art has been defined as that “‘reasonably pertinent to the particular problem with which the inventor was involved.’ ” “To ascertain the scope of the prior art, a court examines the field of the inventor’s endeavor, and the problem with which the inventor was involved, at the time the invention was made.” Content in this context includes material established by the novelty subsections of section 102 of Title 35, United States Code, including, inter alia: 1) printed publications or patents from anywhere in the world published or issued before the date of invention; 2) a United States patent application subsequently issued, and filed before the date of invention; and 3) another’s invention that was made in this country and not abandoned, suppressed, or concealed before the invention date of the invention in question. 2. Level of Ordinary Skill in the Art “[A] person having ordinary skill in the art” for the purpose of section 103 refers to a hypothetical person reasonably skilled in the applicable art. However, this hypothetical person is incapable of thinking outside of the conventional wisdom in the art, as it stood at the time of the claimed invention. “In determining [the level of ordinary skill in the art], the court may consider various factors including [the] type of problems encountered in the art; prior art solutions to those problems; rapidity with which innovations are made; sophistication of the technology; and educational level of active workers in the field.” Every one of these factors need not be present in every case, and one or more factors may predominate. The skill level to be considered is the level at the time the invention was made. 3. Differences Between Claimed Invention and Prior Art When assessing differences between the prior art and the claimed invention, section 103 requires consideration of the invention as a whole. After all, inventions are often merely new combinations of existing principles or features. Absent the “as a whole” requirement: [a]n obviousness assessment might successfully break an invention into its component parts, then find a prior art reference corresponding to each component. This line of reasoning would import hindsight into the obviousness determination by using the invention as a road-map to find its prior art components. This improper method would discount the value of combining various existing features or principles in a new way to achieve a new result — often the essence of invention. Accordingly, when obviousness is based on the teachings of multiple prior art references, the party claiming invalidity must establish a “motivation to combine” the references. This means that there was some “suggestion, teaching, or motivation” that would have led a person of ordinary skill in the art to combine the relevant prior art teachings in the manner claimed. That party must also show that such a combination would have had a reasonable chance of success. Accordingly, “[w]hen determining the patentability of a claimed invention which combines two known elements, ‘the question is whether there is something in the prior art as a whole to suggest the desirability, and thus the obviousness, of making the combination.’” The source of the teaching, suggestion, or motivation may be “the nature of the problem,” “the teachings of the pertinent references,” or “the ordinary knowledge of those skilled in the art.” “Each individual reference must be considered for everything it teaches by way of technology and is not limited to the particular invention it is describing and attempting to protect.” A court must also determine whether the prior art references in question “teach away” from, or discourage, the claimed design. “Broad conclusory statements regarding the teaching of multiple references, standing alone, are not ‘evidence’ [of motivation to combine].” Additionally, to examine obviousness at the time the invention ivas made “requires the oft-difficult but critical step of casting the mind back to the time of invention, to consider the thinking of one of ordinary skill in the art, guided only by the prior art references and the then-accepted wisdom in the field ...” in order to “guard[ ] against entry into the tempting but forbidden zone of hindsight.” This means, among other things, that a court must avoid the temptation to “ ‘use hindsight reconstruction to pick and choose among isolated disclosures in the prior art to deprecate the claimed invention,’ ” and must also avoid “[diefining the problem in terms of its solution.” 4. Objective Evidence of Non-Obviousness/Secondary Considerations The Supreme Court has noted that inquiry into one of several “secondary considerations ... may have relevancy ... as indicia of obviousness or nonobviousness.” These considerations include “commercial success, long felt but unsolved needs, [and] failure of others [to address the problems claimed to be addressed by the patent-in-suit].” Such evidence has long been valued as “a helping hand to the judiciary which ... is most ill-fitted to discharge the technological duties cast upon it by patent legislation.” Secondary considerations also “serve to guard against slipping into use of hindsight.” Although this factor is referred to in seemingly dismissive fashion as “secondary considerations,” the Federal Circuit has made clear that such evidence is not of secondary importance: [Evidence of secondary considerations may often be the most probative and cogent evidence in the record. It may often establish that an invention appearing to have been obvious in light of the prior art was not. It is to be considered as part of all the evidence, not just when the decisionmaker remains in doubt after reviewing the art. Accordingly, a district court must at least consider such evidence before granting summary judgment on obviousness grounds. Nonetheless, a patent can still be found to be obvious on summary judgment even if secondary considerations favor the patentee. For secondary evidence to be accorded substantial weight, its proponent must establish a nexus between the evidence and the merits of the claimed invention. “A prima facie case of nexus is generally made out when the patentee shows both that there is commercial success, and that the thing (product or method) that is commercially successful is the invention disclosed and claimed in the patent.” “[I]f the marketed product embodies the claimed features, and is coextensive with them, then a nexus is presumed and the burden shifts to the party asserting obviousness to present evidence to rebut the presumed nexus.” To the extent that the patentee demonstrates the required nexus, its objective evidence of nonobviousness will be accorded more or less weight. IV. DISCUSSION A. Effect of Cordis Verdict on Validity Medinol argues that because the Cordis jury found claim 13 of the 120 patent not invalid, I cannot find the same claim, and “the other meander claims that have similar limitations,” invalid on summary judgment. Medinol is wrong for two reasons. First, Guidant correctly states that “as there is no such thing as a ‘validity’ verdict, different verdicts — one finding a claim not invalid, the other one finding the same claim invalid — are not necessarily inconsistent.” “[P]atents cannot be held ‘valid’ under all circumstances. Rather, a court merely decides in a particular case that the one attacking validity has not overcome the statutory presumption of validity.” Second, as Guidant was not a party to the Cordis litigation, and as it claims to have new evidence of invalidity, it would be inappropriate to summarily foreclose its arguments as to the “meander” claims, including claim 13 of the 120 Patent. B. Analysis of Graham Factors 1. Scope and Content of Prior Art For purposes of this motion, Guidant relies on only two prior art references: the Lau ’955 Patent and the Fischell ’370 Patent. The general content of this prior art was discussed above. Medinol disputes that the Fischell ’370 Patent, as opposed to the earlier Fischell application that became the Fischell ’312 Patent, is prior art to the patents-in-suit. However, the Fischell ’370 Patent is a continuation of the application that became the ’312 Patent. That application was filed on February 25,1994, but the ’312 Patent was not issued until July 1, 1997, two months after the filing of the application that became the ’370 Patent. For these reasons, the Fischell ’370 Patent claims priority to the application that became the ’312 Patent. Moreover, my earlier Opinion in this case noted that the parties agree that the Fischell ’370 Patent is prior art to the patents-in-suit. Thus, the Fischell ’370 Patent is prior art for purposes of this motion. 2. Level of Ordinary Skill in the Art In Medinol I, I held that “one of ordinary skill in the art is assumed to be an engineer working with a physician or a ‘stent design team,’ who are presumed to know all of the relevant prior art.” The parties broadly agree that this definition should apply now. The only area of disagreement concerns Guidant’s assertion that “the stent design field was becoming increasingly crowded in 1994, serving to expand the knowledge base of a person of skill in the art at this time.” But Guidant provides no support for this assertion, aside from listing a handful of stent design patents granted before 1994. Even if true, this assertion is not of value, because it provides no method for determining whether the knowledge base of a hypothetical person was in fact expanding. Thus, I will adhere to the definition of ordinary skill in the art established in my earlier Opinion and agreed to by the parties. 3. Differences Between the Claimed Invention and the Prior Art a. Presence of Claim Limitations in Lau and/or Fischell Much of Guidant’s opening brief is devoted to demonstrating that each limitation of the patents-in-suit is disclosed by Lau and/or Fischell. However, Guidant also concedes that many of the limitations of the patents-in-suit are present in the prior art only if one combines certain disclosures of Lau and Fischell in a certain way. At the same time, Medinol does not seriously dispute that one could find every claim of the patents-in-suit in Lau, Fischell, or a certain combination of the two references. For this reason, analysis of this factor will necessarily turn on whether a motivation to combine the prior art existed. Thus, I will only briefly summarize the similarities and differences between Lau, Fischell and the patents-in-suit, before turning to whether there was a motivation to combine Lau and Fischell in the manner Guidant claims. The presence of some limitations of the patents-in-suit in the prior art cannot be reasonably disputed. For example, Lau discloses first meanders as construed by the Court, and as required by all asserted claims of the T20 and ’981 Patents. These first meanders include “loops,” and “circumferential members,” within the meaning of this Court’s construction of those terms. Lau also discloses claim 13 of the ’120 patent’s limitation of “an expandable stent formed of an elongated cylindrical unitary tube.” I have already held that Lau Figure 5 discloses “a plurality of enclosed spaces” within the meaning of several of Medinol’s claims. Finally, Lau discloses U or C-shaped structures. I have construed the term “second meander” to mean “a periodic pattern about a center line oriented in a direction different from the axis of the first meanders.” A plurality of second meanders, required by all the asserted claims of the ’120 and ’981 Patents, is disclosed by Lau Figure 5. However, Guidant strains to find second meanders in the Fischell Patent, because this Court’s construction requires that a second meander be accompanied by a first meander. And despite Guidant’s contention, Fischell does not disclose first meanders, because Fischell teaches the desirability of circular rings, rather than the undulating rings of Lau. Moreover, Lau Figure 11, on which Guidant heavily relies as the starting point for its asserted combination of Lau and Fischell, does not have a plurality of second meanders, as the rings of Lau Figure 11 only have one connector. To obtain such a plurality of second meanders in Lau Figure 11, Guidant must add connectors to Lau’s drawing. Guidant similarly depends on a hypothetical combination of Lau and Fischell to find in the prior art several other claims of the patents-in-suit entailing a plurality of second meanders, because the second meanders disclosed in Lau Figure 5 do not otherwise correspond to the limitations of the patents-in-suit. The parties also dispute whether flexible cells, of the type required by the ’381 Patent, appear in the prior art. Again, Guidant relies on its hypothetical combination of Lau and Fischell to find many, if not all, of the required elements of the asserted claims of the ’381 Patent in the prior art. Medinol argues that Guidant cannot use its hypothetical stent to prove the obviousness of the ’381 claims because it “has not provided — and cannot provide — any evidence regarding how flexible or ‘longitudinally stiff Guidant’s fictional stent is.” b. Motivation to Combine In any event, even if every element of the patents-in-suit were present in Lau and/or Fischell, this would not end the inquiry. Guidant must still show a motivation to combine these elements of Lau and Fischell, with a reasonable expectation of success, to arrive at the designs disclosed by the patents-in-suit. Drawing all reasonable inferences in Medinol’s favor — as I must — I conclude that Guidant cannot show the absence of genuine issues of material fact. Guidant’s evidence regarding motivation to combine falls into two categories. First, Guidant asserts that a combination of Lau’s out-of-phase serpentine rings, as pictured in Figure 11, and the undulating connectors disclosed by Figure 8 of Fischell, would produce a stent exhibiting every limitation of the claims at issue in this case. Second, Guidant asserts that “there is evidence that persons skilled in the art of stent design in July 1994 — [the Burmeister engineers] — actually did combine the concepts disclosed in Lau (sinusoidal rings) and Fischell (undulating connectors) in their efforts to design a stent.” As an initial matter, Guidant asserts that “the Lau and Fischell patents are directed to the same problem — creating a flexible stent.” But this statement of the problem is pitched at an improper level of generality. As Medinol notes, the problem of creating a flexible stent as such was solved by the prior creation of the coil stent. In fact, Lau and Fischell are directed to somewhat different problems in the stent art. Specifically, while Lau attempts to achieve a balance between deliverability (i.e. flexibility) and radial support once deployed, the primary concern of Fischell is to achieve sufficient “hoop strength,” for radial support. To be sure, Fischell also teaches that longitudinal predeployment flexibility can be addressed through the use of undulating longitudinals. But Guidant does not adequately explain why a stent designer of ordinary skill, seeking to address the same problems sought to be addressed by the patents-in-suit, would adapt the undulating longitudinals of Fischell Figure 8 to the straight connectors of Lau, but at the same time disregard Fischell’s teachings 1) favoring the use of longitudinals running the length of the stent, as opposed to connectors between each pair of rings; and 2) prescribing the use of circular hoops as opposed to Lau’s meandering rings. Nor does Guidant adequately explain why Lau Figure 11 would be selected as a starting point to combine Lau and Fischell, as opposed to the inphase design of Lau Figure 5, which Lau teaches would minimize or prevent foreshortening (a concern addressed by the patents-in-suit). Similarly, while Guidant correctly notes Lau’s teaching that adding connectors between rings addresses one goal of the patents-in-suit, improved “scaffolding,” preventing harmful gaps between rings, Medinol has raised a serious question as to whether adding connectors for that purpose to Lau Figure 11, as Guidant proposes, is consistent with Lau’s goals and teachings. Guidant attempts to bridge these gaps in its theory by noting that Lau is not explicitly limited to the use of straight, as opposed to longitudinal connectors; and that the term “longitudinal” in Fischell is not explicitly limited to structures that run the length of the stent and connect all the rings. However, neither of these interpretations flow naturally from the teachings of either patent, and to the extent that the parties offer equally plausible interpretations of the prior art, factual disputes must be resolved in Medinol’s favor at the summary judgment stage. The Burmeister Application is offered by Guidant as real-world evidence of motivation to combine. Although Medinol attacks the probative value of this reference on several grounds, two of its arguments can quickly be set aside. First, it is of no consequence whether the Burmeister reference is prior art, because Guidant does not offer it for that purpose. Rather it is offered as evidence of a person of ordinary skill’s contemporaneous motivation to combine prior art. Second> at the time of the invention, the Burmeister inventors did not possess extraordinary skill in the art. Although it is true that both Brown and Euteneuer, who drew Figures 14a and 14b, ultimately became accomplished inventors in the field of interventional cardiology, neither had significant experience in the field in 1994. Accordingly, the Burmeister Application is relevant to whether a person of ordinary skill would be motivated to combine Lau and Fischell. Even so, the Burmeister Application cannot be dispositive here because it does not establish that the claimed combination of prior art carried a reasonable expectation of success. Indeed, Medinol asserts that the design based on Figures 14a and 14b was a failure, as “the design was inflexible, had protrusions into the lumen on expansion, and could leave significant gaps on the outside of a bend.” It may be trae, as Guidant contends, that the design was not a failure as such because it was merely experimental, never intended for development into a marketable product. However, the fact that the design was apparently unsuccessful undercuts its probative value, at least at this stage of the proceedings. 4. Secondary Evidence Medinol has submitted several types of objective evidence of non-obviousness. First, it asserts that the NIR stent met with commercial success, with 2.2 million units sold between 1996-2000. The term “NIR” stent as used by Medinol apparently means both the “original” NIR stent, and a later product called the “NIR Conformer” which incorporated modifications to the end rings of the stent in order to “achieve better conformability, higher radial strength at the end, [and] better trackability.” Second, Medinol asserts that there was a long-felt need in the industry for stents exhibiting the characteristics taught by the patents-in-suit. Third, Medinol asserts that many in the industry, including Guidant, failed to overcome known problems in the prior art stents. Fourth, Medinol notes praise of the stent designs based on the Medinol patents by others in the industry, including Johnson & Johnson, which attempted to buy Medinol’s NIR design, despite already owning the rights to the Fischell ’370 Patent. Guidant first disputes that Medinol has shown the required nexus between the patents-in-suit and the NIR stents. Guidant asserts that Medinol has failed to put forward prima facie evidence to support a nexus, and also notes that one of Medinol’s own experts, Dr. Snyder, testified that he has never analyzed the claims of Medinol’s patents in connection with the NIR stent under this Court’s claim construction. But Guidant itself states that “[t]he original NIR stent is the commercial embodiment of Medinol’s patents.” Medinol, for its own strategic purposes, disputes this apparent admission, asserting in response that “[t]he NIR stent is a commercial embodiment of some claims of some Medinol patents” no longer at issue in this case. Aside from Guidant’s admission, there are few clear indications from the record that the original NIR stent does in fact practice the teachings of the patents-in-suit. Regarding the NIR Conformer, Medinol asserts that “the NIR Conformer stent as a whole is an embodiment of the Patents-in-Suit,” relying on testimony of Richter to that effect. However, Guidant points to the same testimony to make the contrary assertion. Although Medinol’s interpretation of Richter’s testimony seems more plausible, the record as a whole is unclear as to whether the NIR Conformer in fact practices the teachings of the patents-in-suit, creating a disputed issue of material fact that, on this point, cuts against Medinol as it has the initial burden to show a nexus. Accordingly, as the nexus between either of the NIR stents and the patents-in-suit established by this record is uncertain, the weight afforded Medinol’s secondary evidence concerning the original NIR stent is significantly reduced. Aside from the nexus issue, the remainder of Guidant’s response to Medinol’s secondary evidence underscores that there are disputed issues of material fact regarding this factor. For example, Guidant responds to Medinol’s evidence of long-felt need for the invention by providing its own contrary evidence, asserting that a precommercial version of Guidant’s MultiLink stent (the “Bronco”) negated any long-felt need that might have been addressed by Medinol’s patents. Guidant also disputes whether Medinol’s NIR stents were in fact commercially successful, based on the fact that sales fell sharply three years after introduction. Similarly, Guidant’s evidence of problems identified with the NIR stent, offered in response to Medinol’s evidence concerning praise for the invention in the industry, merely creates a disputed issue of fact concerning whether the patents-in-suit in fact met with general praise in the indusr try. For these reasons, consideration of this Gmham factor militates slightly against granting summary judgment. V. CONCLUSION There are no disputed issues of material fact concerning two of the Graham factors: scope and content of the prior art and level of ordinary skill in the art. However, as set forth above, disputed issues of material fact exist regarding the last two Graham factors: differences between the prior art and the claimed invention, and secondary considerations. In particular, on the decisive issue of whether one of ordinary skill in the art in 1994 would have been motivated to combine the Lau and Fischell references to create the claimed invention, both parties offer reasonable interpretations of the teachings of the prior art. Therefore, because I must draw reasonable inferences from the evidence in Medinol’s favor at this stage, Guidant’s motion for summary judgment of invalidity is denied. The Clerk of the Court is directed to close the pending motion [number 66 on the docket sheet], SO ORDERED: . At issue are U.S. Patent Nos.: (1) 5,843,120 ("’120 Patent"); (2) 6,443,982 ("'982 Patent”); and (3) 6,461,381 (" ’381 Patent”) (collectively "patents-in-suit”). Specifically, Medinol alleges that Guidant has willfully infringed Medinol’s patents through the alleged manufacture, use, offer for sale, sale, and/or importation of MULTI LINK PENTA® and MULTI LINK ZETAO systems, which contain stents for implantation in human vessels. . The parties have also filed cross-motions for summary judgment on the issue of infringement, not addressed by this Opinion. . See generally Medinol v. Guidant, 341 F.Supp.2d 301 (S.D.N.Y.2004) ("Medinol I”). On that motion, Guidant asserted that many of the claims asserted by Medinol in this litigation were barred by collateral estoppel due to the jury verdict in Scimed Life Sys., Inc. v. Johnson & Johnson, 225 F.Supp.2d 422 (D.Del.2002) (the "Cordis" litigation). . See generally Medinol v. Guidant, No. 03 Civ. 2604, 2004 WL 2210290 (S.D.N.Y. Sept. 30, 2004) ("Medinol II”). . See Complaint ¶ 5. . See Rule 56.1 Statement of Undisputed Facts in Support of Guidant’s Motion for Summary Judgment of Invalidity ¶ 4 ("Def. 56.1”). . See Complaint ¶¶ 6-7. . A coronary artery is a blood vessel in the heart. See Scimed Life Sys., Inc. v. Johnson & Johnson, 225 F.Supp.2d 422, 425 (D.Del.2002) ("Cordis I”). . See 9/2/04 Markman Hearing Transcript ("Markman Tr.”), at 5-6 (testimony of Jacob Richter). . See Medinol II, 2004 WL 2210290, at *1. . See Markman Tr. at 6 (Richter). . See id. at 6-7 (Richter). Additionally, as I have already noted: The major complications associated with balloon angioplasty are: (1) dissection, where the plaque "cracks” during the procedure, resulting in a flap that falls into the lumen creating a complete occlusion of the artery; (2) recoil of the vessel wall; and (3) restenosis, or renarrowing of the involved arteries, caused by a buildup of scar tissue created by the procedure. However, PTCA is generally less traumatic and expensive than the alternative — coronary artery bypass surgery. Medinol II, 2004 WL 2210290, at *1 n. 8 (internal citations omitted). . Scimed Life Sys., Inc. v. Johnson & Johnson, 87 Fed.Appx. 729, 730 (Fed.Cir.2004) (unpublished decision) ("Cordis II”). . See Cordis I, 225 F.Supp.2d at 425. . See Medinol I, 341 F.Supp.2d at 304 (quotation and citation omitted). . Id. at 305 (citation omitted). . Id. (citation omitted). . See id. For example, Rodney Wolff designed a stent in 1992 (Wolff '404 Patent) for Medtronic, Inc. using coil connectors. Another coil connector design favoring flexibility over radial strength was the Gianturco-Roubin I (GR-I) stent. See Markman Tr. 11-12 (Richter) ("since there is no longitudinal connection at all [in a coil stent], the rings are very free to move relative to each other. This stent is very, very, flexible. But because the rings [of the stent] can easily be pushed away from each other ... [the stent] would allow tissue to protrude between the struts. There is also no good rigidity because the ring[s are] not closed.”). . Medinol I, 341 F.Supp.2d at 305 (citation omitted). . See generally U.S. Patent No. 5,421,955 to Lilip Lau (June 6, 1995) ("Lau '955 Patent”), Exhibit 1 to Declaration of Robert F. Shaffer, counsel for Guidant ("Shaffer Decl.”). This patent is a continuation of a series of patent applications originally filed on October 28, 1991. See id. col. 1 . See generally U.S. Patent Application "Improved Tissue Supporting Devices” to Paul Burmeister, Charles Euteneuer, Brian Brown and Paul Fordenbacher ("Burmeister Application”), Ex. 4 to Shaffer Decl. . See generally U.S. Patent No. 5,879,370 to Robert Fischell et. al. ("Fischell '370 Patent”), Ex. 2 to Shaffer Decl. This patent is a continuation of a patent application originally filed on February 25, 1994. See id. col. 1; see also U.S. Patent No. 5,643,312 to Fischell ("Fischell '312 Patent”), Exhibit 28 to Second Declaration of Fabian D. Gonell, counsel to Medinol ("Gonell Decl.”). References merely to "Fischell” or the "Fischell Patent” refer to the '370 Patent. . Lau '955 Patent col. 1, ll. 45-50. . Id. col. 1, ll. 53-58. . See id. col. 2 ll. 26-29 ("[t]he presently preferred structure for the expandable cylindrical elements which form the stents of the present invention generally have a circumferential undulating pattern, e.g. serpentine.”). . See id. Fig. 5 (in phase); Fig. 11 (out of phase). Guidant commercialized the "in-phase” design as the Multi-Link stent. See Medinol I, 340 F.Supp.2d at 305. . See Lau '955 Patent Fig. 11, described by die patent as "a plain view of a flattened section of a stent illustrating an alternate undulating pattern.” See id. col. 4, 11 8-10; see also id. col. 5, 11. 63-64 (Fig. 11 is an "alternative stent structure”). . Id. col. 1, ll. 65-68. . Id. col. 3, ll. 6-10. . See Cordis II, 87 Fed.Appx. at 735; see also 7/15/04 Deposition Transcript of Brian Brown ("Brown Dep. Tr.”) at Ex. 9, Ex. 20 to Gonell Decl. (declaration of Brown from earlier litigation, stating that his team began work in early 1994 on a project called "dual expansion stents,” involving a stent using self-expansion as well as balloon expansion). . Burmeister Application at B1020 ("Summary of the Invention”). . See Brown Dep. Tr. at 15-16. As of July 1994, Euteneuer and Brown had never filed a single patent application directed to stent design that later issued as a U.S. Patent. See generally Exhibit 20 to Shaffer Decl. (documents from PTO website, so indicating). However, in future years, both became prolific inventors in the field of interventional cardiology, see Brown Dep. Tr. at 146-47 (establishing that Euteneuer now holds over sixty U.S. patents and patent applications, and that Brown holds at least thirty), and held high-level research related positions. See id. at 5-6, 98-100. . See id. at 129 (Burmeister team created "about a dozen” different prototypes for a hybrid stent, involving “different geometries”). . See id. at 115-16; see also Brown Dep. Ex. 9. . Fischell '370 Patent, col. 1, ll. 41-45; see also id. Figs. 1-4. . Id. col. 1, ll. 30-36. . Id. col. 1, ll. 55-58. . Id. col. 1, ll. 63-67. The other two objects of the Fischell patent are: "that the rings are initially in the form of ovals that can be folded to fit onto a cylindrical structure at a distal portion of a stent delivery catheter”; and "that the predeploymenl stent structure is formed as a single piece out of a metal tube having a smaller inside diameter as compared to the outside diameter of an expandable balloon onto which the pre-deployment stent structure is mounted.” Id. col. 1, 11. 59-62; col. 2 11. 1-5. Medinol asserts that Fischell's "longitudinals” must run the length of the stent, see Medinol’s Counterstatement of Facts Pursuant to Local Rule 56.1 in Opposition to Guidant’s Motion for Summary Judgment of Invalidity ("PL 56.1”) ¶ 156 (citing Fischell '370 Patent col. 1,11. 49-50 and Figs. 1-9). . Cordis Corp. v. Medtronic AVE, Inc., 194 F.Supp.2d 323, 355 (D.Del.2002), rev’d on other grounds, 339 F.3d 1352 (Fed.Cir.2003) ("Medtronic") (quoting Fischell's trial testimony). . Pl. 56.1 ¶6 (quoting Trial Testimony of Jacob Richter at 73-76, Medinol Ltd. v. Boston Scientific Corp., 346 F.Supp.2d 575 (S.D.N.Y.2004) ("Richter BSC Trial Testimony”)). . See Medinol II, 2004 WL 2210290, at *2 (citations omitted). . Richter BSC Trial Testimony 346 F.Supp.2d at-■, slip op. at 73. . See U.S. Patent No. 5,449,373, title page. . The parties agree that the patents-in-suit are entitled to a priority date sometime in 1994, but have not specified an exact date. See PL 56.1 ¶ 94 (“the Patents-in-Suit are entitled to a priority date no later than July 28, 1994”); see also Opening Memorandum in Support of Defendants' Motion for Summary Judgment of Invalidity ("Def. Mem.”) at 2, 24 (assuming that 1994 is the operative year for invalidity purposes). The exact priority date of the patents-in-suit is not material for purposes of this motion. . In addition to the patents listed supra at note 1, these include U.S. Patent No. 5,733,-303 to Israel (the '303 Patent) and U.S. Patent No. 5,972,018 to Israel (the '018 Patent). See Complaint ¶¶ 11, 15. . Cordis I, 225 F.Supp.2d at 425. “Foreshortening" refers to the tendency of a stent to contract longitudinally as it expands, while "uniform scaffolding” refers to a stent that after expansion is "very smooth ... continuously pushing the vessel, [and] not letting pieces of the vessel wall protrude between [ ] struts.” Markman Tr. at 16-17 (Richter). . Def. 56.1 ¶2 (citing 12/21/04 Letter from Gonell to Guidant). Accord PL 56.1 ¶ 2. In addition, I granted in part Guidant's motion for summary judgment based on collateral estoppel, eliminating two claims of the '303 and '018 patents. See Medinol I, 341 F.Supp.2d at 327. . For the full text of Medinol's claims, see Medinol I, 341 F.Supp.2d at 307-08. The text of the claims will also be quoted as needed in this Opinion. . "Circumferential” in this context means the material comprising the rings of the stent; while "longitudinal” describes an element that runs for some distance along the length of the stent. However, meander patterns need not be orthogonal to one another. See Medinol II, 2004 WL 2210290, at *6. . Id., 2004 WL 2210290, at *13. . Id. . Id. at *9. . See Def. 56.1 ¶ 19 ("[t]he original NIR stent is the commercial embodiment of Medinol’s patents.”); see Markman Tr. at 15 (Richter) ("the other direction or solution was the NIR stent that was developed along the teaching of the Israel patent by Medinol”). See also infra Part IV.B.4. . See 5/20/04 Richter Deposition Transcript ("Richter Dep. Tr.”) at Ex. 4, Ex. 18 to Gonell Decl. . See PL 56.1 ¶ 197 (citing Guidant's Post-Hearing Brief, Guidant Corp. v. Cordis Corp., Before an Arbitration Panel Convened by the Center for Public Resources Institute for Dispute Resolution ("Arbitration Brief”), Ex. 23 to Gonell Decl. at GC154628). . Id. ¶ 198 (quoting Arbitration Brief at GC154628). . In Cordis, Medinol asserted claims 12 of the '303 Patent; 13 of the '120 Patent; and 35, 47, and 60 of the '018 Patent. See Medinol II, 2004 WL 2210290, at *3 n. 29. . See Medinol I, 341 F.Supp.2d at 310-11. . See id. at 311. . See Pl. 56.1 ¶ 33 (citing Medinol I, 341 F.Supp.2d at 304 n. 3). . Cordis I, 225 F.Supp.2d at 440. However, finding that defendants failed to present clear and convincing evidence such that a reasonable jury could conclude that the claims are invalid for failure to comply with the written description requirement, the court granted plaintiffs’ motion for JMOL as to the "invalidity of claims 12, 35, 47, and 60 [of the '303 and ’018 patents] based on failure to comply with the written description requirement.” Id. at 439. . Id. at 441 n. 5. . Scimed Life Sys., Inc., 87 Fed.Appx. at 735. Specifically, the Federal Circuit cited the testimony of Cordis’s trial expert, Dr. Nigel Buller, as evidence of the existence of compensation for foreshortening in the prior art. Buller testified that stents constructed from combinations of rings and flexible connectors, "as required by the asserted claims of the '303 and '018 patents, were in the prior art.” Id. at 733. . Id. at 735-36. The parties agreed that July 28, 1994 was the operative date for purposes of invalidity because each of the Cordis patents-in-suit were filed as continuations of an earlier patent dated July 28, 1994. Id. at 730. . Id. at 736. . See, e.g., Dana v. E.S. Originals, Inc., 342 F.3d 1320, 1323 (Fed.Cir.2003). . Fed.R.Civ.P. 56(c). . Jeffreys v. City of New York, 426 F.3d 549, 553 (2d Cir.2005) (quoting Anderson v. Liberty Lobby, 477 U.S. 242, 248, 106 S.Ct. 2505, 91 L.Ed.2d 202 (1986)). . Id. (quoting Anderson, 477 U.S. at 248, 106 S.Ct. 2505). . See, e.g., Vermont Teddy Bear Co. v. 1-800 Beargram Co., 373 F.3d 241, 244 (2d Cir.2004) (citing Adickes v. S.H. Kress & Co., 398 U.S. 144, 157, 90 S.Ct. 1598, 26 L.Ed.2d 142 (1970)). . Woodman v. WWOR-TV, Inc., 411 F.3d 69, 75 (2d Cir.2005) (quoting Matsushita Elec. Indus. Co. v. Zenith Radio Corp., 475 U.S. 574, 586, 106 S.Ct. 1348, 89 L.Ed.2d 538 (1986)). . Jeffreys, 426 F.3d at 554 (quoting Fujitsu Ltd. v. Federal Express Corp., 247 F.3d 423, 428 (2d Cir.2001)). "In a patent case, as in any other, summary judgment may be granted when there are no disputed issues of material fact, or when the non-movant cannot prevail on the evidence submitted when viewed in a light most favorable to it." Knoll Pharm. Co. v. Teva Pharms. USA, Inc., 367 F.3d 1381, 1383 (Fed.Cir.2004) (internal citation omitted). . See, e.g., Golden Pac. Bancorp v. FDIC, 375 F.3d 196, 201 (2d Cir.2004). . See 35 U.S.C. § 282. Section 282 also states that "[e]ach claim of a patent (whether in independent, dependent, or multiple dependent form) shall be presumed valid independently of the validity of other claims; [and] dependent or multiple dependent claims shall be presumed valid even though dependent upon an invalid claim." . See, e.g., Enzo Biochem, Inc. v. Gen-Probe, Inc., 424 F.3d 1276, 1281 (Fed.Cir.2005). . Intel Corp. v. United States Int’l Trade Comm’n, 946 F.2d 821, 830 (Fed.Cir.1991) (quoting Colorado v. New Mexico, 467 U.S. 310, 316, 104 S.Ct. 2433, 81 L.Ed.2d 247 (1984)). . Knoll Pharm. Co., 367 F.3d at 1383. . 35 U.S.C. § 103; see also Graham v. John Deere Co., 383 U.S. 1, 13, 86 S.Ct. 684, 15 L.Ed.2d 545 (1966). Section 103(a) states in pertinent part: A patent may not be obtained ... if the differences between the subject matter sought to be patented and the prior art are such that the subject matter as a whole would have been obvious at the time the invention was made to a person having ordinary skill in the art to which said subject matter pertains. . See Graham, 383 U.S. at 17-18, 86 S.Ct. 684; see also Merck & Co. v. Teva Pharm. USA, Inc., 395 F.3d 1364, 1369 (Fed.Cir.2005) (same). . Boehringer Ingelheim Vetmedica, Inc. v. Schering-Plough Corp., 320 F.3d 1339, 1354 (Fed.Cir.2003). “While absolute certainty is not necessary to establish a reasonable expectation of success, there can be little better evidence negating an expectation of success than actual reports of failure.” Id. (internal quotation and citation omitted). . Ruiz v. A.B. Chance Co., 234 F.3d 654, 664 (Fed.Cir.2000) (quoting Stratoflex, Inc. v. Aeroquip Corp., 713 F.2d 1530, 1535 (Fed.Cir.1983)). Prior art “encompasses not only the field of the inventor’s endeavor but also any analogous arts.” In re GPAC Inc., 57 F.3d 1573, 1577-78 (Fed.Cir.1995). . Monarch Knitting Mach. Corp. v. Sulzer Morat GmbH, 139 F.3d 877, 881 (Fed.Cir.1998) (internal quotation and citation omitted). . See 35 U.S.C. § 102. . See, e.g., In re GPAC Inc., 57 F.3d at 1579 (citation omitted). . See, e.g., Life Techs., Inc. v. Clontech Labs., Inc., 224 F.3d 1320, 1325 (Fed.Cir.1995); Standard Oil Co. v. American Cyanamid Co., 774 F.2d 448, 454 (Fed.Cir.1985) ("A person of ordinary skill in the art is ... not one who undertakes to innovate, whether by patient, and often expensive, systematic research or by extraordinary insights, it makes no difference which.”). . Ruiz, 234 F.3d at 666-67 (quotation and citation omitted). . See id. at 667 (citation omitted). . See Mitsubishi Elec. Corp. v. Ampex Corp., 190 F.3d 1300, 1309 (Fed.Cir.1999). . See Princeton Biochem., Inc. v. Beckman Coulter, Inc., 411 F.3d 1332, 1337 (Fed.Cir.2005). . See id. (citing Environmental Designs, Ltd. v. Union Oil Co., 713 F.2d 693, 698 (Fed.Cir.1983) (noting that "virtually all [inventions] are combinations of old elements”)). . Princeton Biochem., Inc., 411 F.3d at 1337. Accord Ruiz, 357 F.3d at 1275. . There is some inconsistency in the caselaw regarding the relation of "motivation to combine” to the Graham analysis. For example, some Federal Circuit decisions analyze motivation to combine as part of the scope and content of the prior art, see, e.g., Monarch Knitting Mach. Corp., 139 F.3d at 881-83, but the Federal Circuit suggested in 2001 that motivation to combine is a separate inquiry from the Graham factors. See McGinley v. Franklin Sports, 262 F.3d 1339, 1351 (Fed.Cir.2001). However, the latest relevant Federal Circuit decision treats motivation to combine as flowing naturally from the Graham factor measuring differences between the pri- or art and the claimed invention. See Princeton Biochem., Inc., 411 F.3d at 1337 (even if prior art discloses every element of claimed invention, motivation to combine must be shown). Accordingly, I will examine motivation to combine as part of this factor. . See, e.g., Tec Air, Inc. v. Denso Mfg. Mich. Inc., 192 F.3d 1353, 1359-60 (Fed.Cir.1999); Pro-Mold & Tool Co. v. Great Lakes Plastics, Inc., 75 F.3d 1568, 1572 (Fed.Cir.1996). "Even if all [the patent-in-suit's] limitations could be found in the total set of elements contained in the prior art references, a claimed invention would not be obvious without a demonstration of the existence of a motivation to combine those references at the time of the invention.” National Steel Car, Ltd. v. Canadian Pac. Ry., Ltd., 357 F.3d 1319, 1337 (Fed.Cir.2004). To be sure, the motivation to combine need not be expressly stated. See Riverwood Int’l Corp. v. The Mead Corp., 212 F.3d 1365, 1366 (Fed.Cir.2000). . See Boehringer, 320 F.3d at 1354; see also Brown & Williamson Tobacco Corp. v. Philip Morris, Inc., 229 F.3d 1120, 1124-25 (Fed.Cir.2000). . Akamai Techs., Inc. v. Cable & Wireless Internet Servs., Inc., 344 F.3d 1186, 1196 (Fed.Cir.2003) (quoting In re Beattie, 974 F.2d 1309, 1311 (Fed.Cir.1992)). . In re Rouffet, 149 F.3d 1350, 1355 (Fed.Cir.1998). Accord Akamai Techs., Inc., 344 F.3d at 1196. . EWP Corp. v. Reliance Universal Inc., 755 F.2d 898, 907 (Fed.Cir.1985) (emphasis in original). . See, e.g., Syntex (U.S.A.) LLC v. Apotex, Inc., 407 F.3d 1371, 1378 (Fed.Cir.2005). . In re Dembiczak, 175 F.3d 994, 999 (Fed.Cir.1999), abrogated on other grounds by In re Gartside, 203 F.3d 1305, 1316 (Fed.Cir.2000). Accord Ecolochem, Inc. v. Southern Calif. Edison Co., 227 F.3d 1361, 1372 (Fed.Cir.2000). . In re Dembiczak, 175 F.3d at 999. . Ecolochem, Inc., 227 F.3d at 1371 (quoting In re Fine, 837 F.2d 1071, 1075 (Fed.Cir.1988)). . Monar