UNITED STATES INTERNATIONAL TRADE COMMISSION
`Washington, D.C.
`
`In the Matter of
`CERTAIN BALLOON DILATION
`DEVICES, SYSTEMS, AND
`COMPONENTS THEREOF
`Inv. No. 337-TA-1449
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`ORDER NO. 15: CONSTRUING CERTAIN CLAIM TERMS
`(December 8, 2025)
`I. BACKGROUND
`The Commission instituted this investigation to determine whether certain balloon dilation
`devices, systems, and components thereof infringe various claims of U.S. Patent Nos. 11,083,878,
`11,090,472, and 12,274,847. 90 Fed. Reg. 22116 (May 23, 2025). The complainants are Entellus
`Medical, Inc., Stryker Corporation, and Stryker Sales, LLC . Id. The Respondents are Fiagon
`GmbH, Fiagon AG Medical Technologies, Fiagon NA Corporation, Fiagon NA, LLC, and
`Hemostasis, LLC. Id. at 22116–17. The Commission Investigative Staff is not a party. Id. at 22117.
`The parties filed a joint chart identifying agreed and disputed claim terms , Joint Chart
`(EDIS Doc. ID 857769) , and filed initial and responsive claim construction briefs . Stryker Br.
`(EDIS Doc. ID 859741 ); Fiagon Br. (EDIS Doc. ID 859685) ; Stryker Reply (EDIS Doc.
`ID 860769); and Fiagon Reply (EDIS Doc. ID 860761). The parties filed expert declarations with
`their claim construction briefs. Stryker Br., Ex. A ( Griffis Decl.) ; Fiagon Br., Exs. 17 and 22
`(Burban Decl. and Brodner Decl.); Stryker Reply, Ex. C (Griffis Reply Decl.); and Fiagon Reply,
`Ex. 55 (Brodner Reply Decl.). No expert testified at the claim construction hearing and none were
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`deposed before the hearing. 9/8/2025 Tr. at 135:11–17 (EDIS Doc. ID 861451). The parties used
`demonstrative exhibits . Stryker Demonstratives (EDIS Doc. ID 861269) and Fiagon
`Demonstratives (EDIS Doc. ID 861715). Stryker filed Exhibits D–S with its demonstratives. After
`the hearing, both parties filed supplemental briefing. Stryker Supp. Br. (EDIS Doc. ID 861645)
`and Fiagon Supp. Br. (EDIS Doc. ID 861715).
`This order construes certain terms the parties proposed for construction.
`II. RELEVANT LAW
`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). “[T]here is no magic formula or catechism for conducting claim
`construction.” Id. at 1324. Instead, weight may be attached to appropriate sources “in light of the
`statutes and policies that inform patent law.” Id.
`The terms of a claim are generally given their ordinary and customary meaning, which is
`the meaning that the term would have to one of skill in the art at the time of the invention. Id . at
`1312–13. The ordinary meaning of a claim term is its meaning to one of skill in the art after reading
`the entire patent. Id. at 1321. 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).
`In addition to the specification, a court “should also consider the patent’s prosecution
`history, if it is in evidence.” Markman v. Westview Instruments, Inc., 52 F.3d 967, 980 (Fed. Cir.
`1995), aff’d, 517 U.S. 370 (1996) . The prosecution history, which is intrinsic evidence, is “the
`complete record of the proceedings before the PTO 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 i nventor understood the invention
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`and whether the inventor limited the invention in the course of prosecution, making the claim scope
`narrower than it would otherwise be.” Id. “[B]ecause the prosecution history represents an ongoing
`negotiation between the PTO and the applicant, rather than the final product of that negotiation, it
`often lacks the clarity of the specification and thus is less useful for claim construction
`purposes.” Id.
`In some situations, a “court will need to look beyond the patent’s intrinsic evidence and to
`consult extrinsic evidence in order to understand, for example, the background science or the
`meaning of a term in the relevant art during the relevant time period .” Teva Pharms. USA, Inc. v.
`Sandoz, Inc., 574 U.S. 318, 331 (2015) . Extrinsic evidence is “all evidence external to the patent
`and prosecution history, including expert and inventor testimony, dictionaries, and learned
`treatises.” Markman, 52 F.3d at 980.
`While 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 skill in the art,” such testimony
`is “generated at the time of and for the purpose of litigation and thus can suffer from bias that is
`not present in intrinsic evidence.” Phillips, 415 F.3d at 1318. “ The effect of that bias can be
`exacerbated if the expert is not one of skill in the relevant art or if the expert’s opinion is offered
`in a form that is no t subject to cross -examination.” Id. Further, while extrinsic evidence may be
`useful, 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 1319. Where the intrinsic record unambiguously describes the scope of the
`patented invention, reliance on extrinsic evidence is improper. See Pitney Bowes, Inc. v. Hewlett-
`Packard Co., 182 F.3d 1298, 1308 (Fed. Cir. 1999), citing Vitronics, 90 F.3d at 1583.
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`III. LEVEL OF ORDINARY SKILL
`Stryker argues that one of skill “ would have a background in the engineering, design,
`development, use, or manufacture of ear, nose or throat balloon dilation devices and systems. Such
`a [person] would have an educational background in mechanical engineering, biomedical
`engineering, or a related technical field, and/or would have approximately 2–4 years of equivalent
`industry experience with ear, nose or throat balloon dilation devices and systems .” Stryker Br.
`at 13 and Griffis Decl. ¶ 20. Fiagon argues that one of skill in the art “ would have had an
`educational background in biomedical engineering, electrical engineering, mechanical
`engineering, chemical engineering, or an equivalent or a Doctor of Medicine (MD) or equivalent,
`or would have 1–2 years of experience designing or using medical instruments.” Fiagon Br. at 10
`and Burban Decl. ¶ 41.
`The parties agree that their dispute as to the level of skill is not relevant to any claim
`construction dispute. 9/8/2025 Tr. at 14:17–25. To the extent I must determine the appropriate
`level of skill in the art, I adopt Fiagon’s proposed definition. Cf. Genzyme Therapeutic Prods. Ltd.
`P’ship v. Biomarin Pharm. Inc., 825 F.3d 1360, 1372 (Fed. Cir. 2016) (failure to make a specific
`finding about the required level of skill in the art is not reversable error where the record did not
`show any meaningful differ ences in proposed definitions or that the outcome of the case would
`have been different based on which definition was selected).
`IV. THE ASSERTED PATENTS
`The asserted patents each claim priority to the same parent application. ’878 patent (Fiagon
`Ex. 1) at cover; ’472 patent (Fiagon Ex. 2) at cover; ’847 patent (Fiagon Ex. 3) at cover. Each is
`titled “Method and Articles for Treating the Sinus System.” Id.
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`end of the inner guide member, wherein the first port is in fluid
`communication with the lumen at the proximal end of the inner guide
`member;
`a shaft mounted about a periphery of the inner guide member , wherein a
`portion of the inner guide member extends distally of a distal end of the
`shaft;
`* * *
`wherein the distal portion of the inner guide member is malleable
`Claim 1 of the ’878 patent thus recites structure of both the inner guide member and shaft but does
`not explicitly recite that they are movable relative to each other. The claim also recites that the
`distal portion of the inner guide member is malleable.
`Claim 22 of the ’878 patent recites:
`22. A method of treating a drainage pathway of a sinus cavity, the method
`comprising:
`providing a balloon dilation catheter comprising:
`* * *
`an inner guide member comprising a proximal portion and a distal portion,
`wherein the proximal portion of the inner guide member is in the handle,
`wherein the distal portion of the inner guide member extends distally from
`the distal end of the handle, wherein the inner guide m ember comprises a
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`lumen extending from a proximal end of the inner guide member to a distal
`end of the inner guide member,
`a shaft mounted about a periphery of the inner guide member, wherein a
`portion of the inner guide member extends distally of a distal end of the
`shaft,
`* * *
`forming a bend in the inner guide member at a location that is distal to a
`distal end of the support member to change a shape of the inner guide
`member;
`after forming the bend in the inner guide member, advancing, via a nasal
`passageway, the inner guide member to a target location in a drainage
`pathway of a sinus cavity; and
`after advancing the inner guide member to the target location, inflating the
`inflatable balloon to dilate the drainage pathway of the sinus cavity,
`wherein inflating the inflatable balloon is performed while the inflatable
`balloon extends along the bend in the inner guide member.
`Like claim 1, claim 22 recites structure of both the inner guide member and shaft and does not
`explicitly recite that they are movable relative to each other. And while claim 1 recites that the
`inner guide member is malleable, claim 22 recites that it has a bend at a distal portion, that a
`balloon extends along the bend, and that it is advanced to a target location in a sinus.
`Claim 1 of the ’472 patent recites:
`1. A balloon dilation catheter comprising:
`* * *
`an inner guide member comprising a proximal portion and a distal portion,
`wherein the proximal portion of the inner guide member is in the handle,
`wherein the distal portion of the inner guide member extends distally from
`the distal end of the handle, wherein the inner guide m ember comprises a
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`lumen extending from a proximal end of the inner guide member to a distal
`end of the inner guide member;
`a shaft mounted about a periphery of the inner guide member, wherein a
`portion of the inner guide member extends distally of a distal end of the
`shaft;
`* * *
`wherein a distal end of the support member is located proximal to a bend in
`the inner guide member, and
`wherein the inflatable balloon is inflatable with the inflatable balloon
`extending along the bend in the inner guide member.
`Like claims 1 and 22 of the ’878 patent , claim 1 of the ’472 patent recites structure of both the
`inner guide member and shaft and does not explicitly recite that they are movable relative to each
`other. Claim 1 of the ’472 patent also recites that the inner guide member has a bend and that a
`balloon extends along the bend.
`Claim 24 of the ’472 patent recites:
`24. A balloon dilation catheter comprising:
`* * *
`an inner guide member comprising a proximal portion and a distal portion,
`wherein the proximal portion of the inner guide member is in the handle,
`wherein the distal portion of the inner guide member extends distally from
`the distal end of the handle, wherein the inner guide m ember comprises a
`lumen extending from a proximal end of the inner guide member to a distal
`end of the inner guide member;
`a shaft mounted about a periphery of the inner guide member, wherein a
`portion of the inner guide member extends distally of a distal end of the
`shaft;
`* * *
`wherein the light-fiber is configured to be removed from the lumen of the
`inner guide member while the inner guide member is positioned in a
`maxillary sinus structure or a frontal sinus structure.
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`Like claims 1 and 22 of the ’878 patent and claim 1 of the ’472 patent, claim 24 of the ’472 patent
`recites structure of both the inner guide member and shaft and does not explicitly recite that they
`are movable relative to each other. Similar to claim 22 of the ’878 patent, claim 24 of the ’472
`patent recites that the inner guide member of positioned within a sinus structure.
`Claim 30 of the ’472 patent recites:
`30. A balloon dilation catheter comprising:
`* * *
`an inner guide member comprising a proximal portion and a distal portion,
`wherein the proximal portion of the inner guide member is in the handle,
`wherein the distal portion of the inner guide member extends distally from
`the distal end of the handle, wherein the inner guide m ember comprises a
`lumen extending from a proximal end of the inner guide member to a distal
`end of the inner guide member, wherein the inner guide member is a
`hypotube formed from stainless steel, wherein the distal portion of the inner
`guide member is malleable;
`a shaft mounted about a periphery of the inner guide member, wherein a
`portion of the inner guide member extends distally of a distal end of the
`shaft;
`Like claim 1 of the ’878 patent, claim 1 of the ’472 patent recites structure of the inner guide
`member and shaft but does not explicitly recite that they are movable relative to each other and
`recites that the distal portion of the inner guide member is malleable.
`Claim 1 of the ’847 patent recites:
`1. A balloon dilation device comprising:
`* * *
`an inner guide member comprising a proximal portion and a distal portion,
`wherein the proximal portion of the inner guide member is in the handle,
`wherein the distal portion of the inner guide member extends distally from
`the distal end of the handle, wherein the inner guide m ember comprises a
`lumen extending from a proximal end of the inner guide member to a distal
`end of the inner guide member, wherein the distal portion of the inner guide
`member is malleable such that the distal portion of the inner guide member
`is configured to be shaped with an angle of 0 degrees to 120 degrees relative
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`to the proximal portion of the inner guide member, wherein the inner guide
`member is a stainless steel hypotube;
`a polymeric shaft1 mounted about a periphery of the inner guide member;
`and
`Like claims 1 of the ’878 and ’472 patents, claim 1 of the ’847 patent recites structure of both the
`inner guide member and shaft but does not explicitly recite that they are movable relative to each
`other and recites that the distal portion of the inner guide member is malleable . Claim 12 of the
`’847 patent is similar. Id. at claim 12.
`As is evident from the claim language, none of the asserted independent claims recites a
`movable shaft or that the shaft and inner guide member move relative to each other. Fiagon points
`to no claim language relating to the shaft that supports it must be moveable. Instead, Fiagon argues
`that the word “guide” in the claimed inner guide member supports that the shaft is moveable.
`Fiagon Br. at 13. In particular, Fiagon contends that the “term ‘guide’ is not surplusage; its ordinary
`meaning requires directing the course of something in motion.” Id. And according to Fiagon, that
`something in motion is the shaft . But Fiagon points to nothing in the claim language supporting,
`much less requiring, that use of the word “guide” means that the shaft is movable relative to the
`guide.
`Fiagon is correct that the word “guide” cannot be superfluous . Other claim language
`supports the structure of the inner guide member and that it is malleable (’872 patent claim 1, ’472
`patent claim 30, and ’847 patent claims 1 and 12 ), has a bend along which a balloon is located
`(’878 patent claim 22 and ’472 patent claim 1), and is advanced to a target location /sinus (’878
`patent claim 22 and ’472 patent claim 24 ). Fiagon is incorrect that the claim language here does
`not answer the question of what is being guided. Fiagon Supp. Br. at 3. The recitations that the
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`1 The parties do not argue that “polymeric” is relevant to their dispute.
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`inner guide member is malleable, has a bend with a balloon on it, and is advanced to a target
`location supports that the guiding performed by the inner guide member is relative to the overall
`operation of the claimed balloon catheter device. Fiagon’s expert, Dr. Burban, recognized that the
`words “malleable” and “bend” support use of the inner guide member as treating sinus passages.
`Burban Decl., ¶¶ 78–81. In addition, that the inner guide member recited in claim 22 of the ’878
`patent and claim 24 of the ’472 patent is moved into a sinus further supports that the guide function
`of the inner guide member is satisfied by its “ ability to position a distal portion of the balloon
`dilation catheter into a desired location.” Stryker Reply at 4, citing Griffis Reply Decl. ¶¶ 13–14.
`Fiagon contends that “the inner guide member does not guide the device into the sinus
`passage. Fiagon Reply at 7 (emphasis in original). This is inconsistent w ith the claim language,
`the specification, Fiagon’s expert, and common sense. In addition, that lights or sensors can
`indicate “where the distal tip of the inner guide member is located,” as Fiagon contends, id., does
`not mean that the inner guide member does not guide the catheter into the sinus passage. Based on
`the claims as a whole, the word “guide,” therefore, means that the ballon catheter itself is guided
`and does not require that the shaft and inner guide member are movable relative to each other.
`Fiagon points to a 2004 Merriam Webster dictionary and contends that it defines “guide”
`as “a device to direct the motion of something.” Id ., Fiagon Br. at 13, citing Fiagon Ex. 18. This
`fourth definition of “guide” outside the context of the claimed invention does not support that the
`word “guide” in the claims necessarily requires motion of the shaft relative to the inner guide
`member.
`Further, claims in other related patents specifically recite that the shaft is movable relative
`to the inner guide membe r. As Fiagon notes, “[f]or 11.5 years —from June 2009 to December
`2020—each related application Complainants filed with claims featuring a balloon catheter
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`expressly claimed a movable shaft that allowed a balloon to be advanced and retracted over an
`inner guide member.” Fiagon Br. at 6 (emphasis in original). Fiagon’s 10-page chart details earlier
`claims in the same patent family expressly reciting that the shaft is movable relative to the inner
`guide member. Fiagon Ex. 4 and Stryker Supp. Br. at 5. For example, the independent claims of
`U.S. Patent No. 8,277,478 recite a “movable knob operatively coupled to the shaft, wherein distal
`advancement of the knob advances the shaft and balloon relative to the substantially rigid inner
`guide in a distal direction.” Fiagon Ex. 4 at 1. The independent claims of U.S. Patent.
`No. 8,282,667 recite “a movable shaft” with limitations describing movement of the shaft along
`the inner guide member. Id. at 1–3. Other patents are similar, expressly reciting movability of the
`shaft along the inner guide member. See generally Fiagon Ex. 4 at 3–10.
`The omission of any recitation indicating that the shaft is movable relative to the inner
`guide member in the asserted claims, when that has been claimed many times in earlier -issued
`related patents, supports that the patentee did not intend to limit the asserted claims that way. See
`E.I. du Pont De Nemours & Co. v. Unifrax I LLC , 921 F.3d 1060, 1069–70 (Fed. Cir. 2019)
`(consideration of related application as intrinsic evidence); Advanced Cardiovascular Sys., Inc. V.
`Medtronic, Inc., 265 F.3d 1294, 1305–06 (Fed. Cir. 2001) (the absence of a claim term in a related
`patent indicates intent to broaden scope) and see Stryker Reply at 8–9.
`In addition, dependent claims 5 and 21 of the ’847 patent recite that the shaft comprises a
`“rider lumen.” The specification explains that the rider lumen “enables the shaft 30 to advance and
`retract over the inner support guide 14 in a close-fit arrangement.” ’847 patent at 7:23–46 and see
`Fiagon Br. at 15. As noted by Stryker, the inclusion of an element reciting movability of the shaft
`relative to the inner guide member in dependent claims supports a presumption that this element
`is not included in claims that do not include this element. Stryker Reply at 6 and see Phillips, 415
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`F.3d at 1315. Fiagon contends that this claim differentiation point is incorrect because the rider
`lumen and any details of it are not in its proposed construction. 9/8/2025 Tr. at 59–60. While that
`is true, and while not dispositive, the only express indication of movability of the shaft relative to
`the internal guide member in any of the claims of the asserted patents is the recitation of the rider
`lumen, at least suggesting that the independent claims do not have a moveability requirement.
`The language of the asserted claims, the language of independent claims in earlier and
`related patents, and certain dependent claims in the ’847 patent support that there is no requirement
`of movability of the shaft relative to the internal guide member in the asserted claims.
`Fiagon argues that the “specification consistently, repeatedly, and exclusively describes
`the shaft and balloon as sliding or advancing over the ‘inner guide member.’” Fiagon Br. at 13;
`Fiagon Reply at 4; and see Fiagon Ex. 20. Stryker does not seriously dispute this characterization,
`arguing instead that absent a clear and unmistakable disavow al, it is entitled to the full scope of
`the claims as written, that is, with no movability requirement. Stryker Br. at 17–18 and 22 and
`Stryker Reply at 4–6.
`While the specification includes multiple disclosures of a movable shaft, the claims do not
`explicitly require such a shaft. The Federal Circuit has explained “it is improper to read limitations
`from a preferred embodiment described in the specification—even if it is the only embodiment—
`into the claims absent a clear indication in the intrinsic record that the patentee intended the claims
`to be so limited.” Liebel-Flarsheim Co. v. Medrad, Inc., 358 F.3d 898, 913 (Fed. Cir. 2004) ; see
`also Thorner v. Sony Comput. Ent’t Am. LLC, 669 F.3d 1362, 1366 (Fed. Cir. 2012) (“It is likewise
`not enough that the only embodiments, or all of the embodiments, contain a particular limitation.
`We do not read limitations from the specification into claims; we do not redefine words. ”). For
`there to be an implied redefinition, it “must be so clear that it equates to an explicit one.” Thorner,
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`669 F.3d at 1368. The evidence does not support that there has been an implied redefinition of
`“shaft” as a “movable shaft” or that movability of the shaft is essential to the invention . Nothing
`in the language of “shaft” or “inner guide member” as recited in the claims requires a movable
`shaft and there is not an explicit or implicit redefinition of the terms in the specification.2
`In addition, there is no “repeated[] disparag[ement]” of a non-movable shaft. Indivior Inc.
`v. Dr. Reddy’s Labs., S.A., 930 F.3d 1325, 1337 (Fed. Cir. 2019) (where the specification made
`clear that one type of drying does not produce “uniform” films, it was appropriate to exclude that
`type of drying from the scope of the term “dried.” ); Chicago Bd. Options Exch., Inc. v. Int’l Sec.
`Exch., LLC, 677 F.3d 1361, 1371–72 (Fed. Cir. 2012) (open-outcry or floor-based trading systems
`were excluded because the claim recited “automated exchange.”); Honeywell Intern., Inc. v. ITT
`Indus., Inc. 452 F.3d 1312, 1319–20 (Fed. Cir. 2006) (disavowing a class of fibers from
`“electrically conductive fibers”) ; and see Stryker Supp. Br. at 5. There are also “no words of
`manifest exclusion or restriction. ” Hill-Rom Servs., Inc. v. Stryker Corp.,755 F.3d 1367, 1372
`(Fed. Cir. 2014). The patent does not “describe the invention as limited to” a movable shaft. “There
`is no disclosure that, for example, the present invention ‘is,’ ‘includes,’ or ‘refers to’” a movable
`shaft. Id. While a movable shaft is disclosed as a benefit, the specification does not identify that
`feature as essential or required.
`Fiagon also argues that the term “inner guide member” is a coined term. Fiagon Reply at 3
`and 5 and Fiagon Supp. Br. at 2. Fiagon’s reliance on Iridescent Networks, Inc. v. AT&T Mobility,
`LLC, however, is not helpful. There, the Federal Circuit considered the term “high quality of
`service connection,” which was “a term of degree that is not a known term of art, but rather a term
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`2 In a footnote, Fiagon contends that if the claims are not construed with its movability requirement,
`they lack written description. Fiagon Br. at 10 n.7. That issue is not decided here.
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`coined by the patentee.” 933 F.3d 1345, 1349– 50 (Fed. Cir. 2019) (internal quotation marks
`omitted). Because the bounds of this “coined term of degree” were not known from the claim
`language, it was appropriate to construe the term based on information, including numerical
`values, in the specification and prosecution history. Id . at 1351–54. Likewise, Interval Licensing
`LLC v. AOL, Inc ., on which Iridescent relies, considered the meaning of the “purely subjective”
`term of degree “unobtrusive manner.” 766 F.3d 1364, 1371 (Fed. Cir. 2014). The term “inner guide
`member” is in no way similar to the terms of degree recited in Iridescent or Interval Licensing and
`there is, therefore, no need to define the term by certain embodiments disclosed in the specification.
`Fiagon’s reliance on Irdeto Access v. Echostar Satellite Corp. fares no better. Fiagon Supp.
`Br. at 2. There, during prosecution, the Examiner stated that certain claim terms had no accepted
`meaning and that they should be differentiated. 383 F.3d 1295, 1298 (Fed. Cir. 2004). The patentee
`in response agreed that there was no accepted meaning and pointed to the specification for
`definitions of the identified terms. Id. The Federal Circuit found that, “[h]aving conceded that the
`[identified terms] have no accepted meaning in the art, the applicant expressly directed the public
`to the specification to discern that meaning and thus measure the scope of the claimed invention.”
`Id. at 1300.
`Fiagon argued at the hearing that:
`the best evidence that this is a term that is a coined term is that we have three
`inventors who have been deposed in this case and not one of them knew what the
`term meant. So when counsel says this term would be readily understandable to
`[one of skill] that’s just not credible . . . when the three inventors don't even know
`what the term means.
`9/8/2025 Tr. at 33:3–9.
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`3 Because Fiagon relied on deposition testimony taken after claim construction briefing was
`completed, I allowed the parties to provide supplemental briefing, which they did. Tr. at 34:16–
`35:8 and 71:4–13.
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`Inventor testimony is extrinsic evidence, which is unlikely to meaningfully assist with
`claim construction. See Unwired Planet LLC v. Google, Inc., 660 F. App'x. 974, 984 (Fed. Cir.
`2016) (“the district court wrongly relied on the inventor ’s testimony about his subjective
`understanding of the meaning of” the claim term at issue because “this testimony is irrelevant as a
`matter of law”). The Federal Circuit has explained:
`Whether an inventor ’s testimony is consistent with a broader or narrower claim
`scope, that testimony is still limited by the fact that an inventor understands the
`invention but may not understand the claims, which are typically drafted by the
`attorney prosecuting the patent application. As we have explained, “it is not unusual
`for there to be a significant difference between what an inventor thinks his patented
`invention is and what the ultimate scope of the claims is after allowance by the
`PTO.”
`Howmedica Osteonics Corp. v. Wright Medical Technology, Inc., 540 F.3d 1337, 1346–47 (Fed.
`Cir. 2008) (quoting Markman, 52 F.2d at 985). This is so even if the inventor’s testimony is against
`his own interest. Id. at 1347. In addition to being legally irrelevant, the inventors here primarily
`testified that “inner guide member” was not a term they used in their work and not a term with
`which they were familiar. Fiagon Ex. 56 at 99:9–19; Fiagon Ex. 62 at 124:12–20; and Fiagon Ex.
`63 at 90:21–91:10. That this was so does not support that this term would not have meaning to one
`of skill in the context of the asserted patents . The evidence does not support that “inner guide
`member” is a coined term, as argued by Fiagon.
`The specification does not support interpreting the claimed shaft and inner guide member
`as movable relative to each other.
`Fiagon relies on the prosecution histor ies of other patents in the family to support its
`construction, arguing that Stryker disclaimed catheters other than those with movable shafts .
`Fiagon Br. at 15 –18 and Fiagon Reply at 3–7. But as Stryker notes , the statements in th ose
`prosecution histories relate to claims that explicitly recited a movable shaft. Stryker Reply at 9.
`For example, while Fiagon highlights the prosecution of U.S. Patent No. 10,369,337 and the
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`patentee’s statement that “there is no ‘inner guide member’ in” the prior art, Fiagon Reply at 3 and
`Fiagon Ex. 10, the claim there recited a slidably arranged shaft and a movable shaft advancing
`member. Fiagon Ex. 10 at 025677. In addition, before stating that the prior art had no inner guide
`member, the patentee argued that there was not disclosure of its “outer tube 325 being advanced
`(or advanceable) over the inner tube 326.” Id. Movability, therefore , was not only claimed, but
`was central to the patentee’s arguments.
`The Federal Circuit has explained when the prosecution history of a related patent may be
`relevant to claim construction:
`The prosecution history of a related patent can be relevant if, for example, it
`addresses a limitation in common with the patent in suit. However, if the limitations
`at issue are dissimilar, we generally cannot accept, without more support, that an
`applicant’s disclaimer with respect to one claim would be equally applicable to
`another claim. This is because a patentee is free to take a different approach to
`claiming an invention in subsequent patents, either by adding limitations or by
`altering the claims’ format. Thus, unless there is parity between the limitations, we
`cannot assume that the claims of an earlier, related patent present similar issues of
`validity to the later patent or that the applicant’ s disclaimer with respect to an
`earlier, related claim would be equally applicable to the later claim. In other words,
`for prosecution disclaimer to apply, the related patents must have limitations in
`common to support the inference that the patentee ’s earlier arguments are also
`applicable to the claim limitations of the patent-in-suit.
`Maquet Cardiovascular LLC v. Abiomed Inc., 131 F.4th 1330, 1339–40 (Fed. Cir. 2025) (internal
`quotations and citations omitted). The holding in Maquet is on point. There, the Federal Circuit
`concluded that arguments made during prosecution of a parent patent were not relevant to the
`asserted patent because the parent patent recited a lumen with a specific position and length,
`whereas the claim of the asserted patent did not. Id. at 1440. Likewise here, Fiagon relies on the
`prosecution histories of related patents with claims requir ing the shaft to move along the inner
`guide member, whereas the claims here have no such requirement. See Fiagon Br. at 17–18. Fiagon
`seeks to get around this explicit change by focusing not on the “sha ft” but the “inner guide
`member” term. 9/8/2025 Tr. at 56:6–20. This, as explained previously, is unpersuasive. The
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`19
`14. The balloon dilation catheter of claim 1, further comprising a means for
`determining a location of the distal end of the inner guide member within at least
`one anatomic structure,
`wherein the inflatable balloon is adapted to dilate the at least one anatomic
`structure,
`wherein the at least one anatomic structure is selected from a group
`consisting of: a sinus cavity, a drainage pathway of the sinus cavity, and an
`ostium of the sinus cavity, and
`wherein the sinus cavity is selected from a group consisting of a maxillary
`sinus cavity, a frontal sinus cavity, an ethmoid sinus, and a sphenoid sinus
`cavity.
`’878 patent at claim 14. Claim 19 of the ’472 patent recites the same means language, namely, “a
`means for determining a location of the distal end of the inner guide member within t