Case: 21-2316     Document: 72    Page: 1   Filed: 06/09/2023




   United States Court of Appeals
       for the Federal Circuit
                   ______________________

 BLUE GENTIAN, LLC, NATIONAL EXPRESS, INC.,
        TELEBRANDS CORPORATION,
             Plaintiffs-Appellants

                             v.

                TRISTAR PRODUCTS, INC.,
                     Defendant-Appellee
                   ______________________

                    2021-2316, 2021-2317
                   ______________________

     Appeals from the United States District Court for the
 District of New Jersey in No. 1:13-cv-01758-NLH-AMD,
 Judge Noel Lawrence Hillman.
                 ______________________

                    Decided: June 9, 2023
                   ______________________

     MICHAEL HAWES, Baker Botts LLP, Houston, TX, ar-
 gued for all plaintiffs-appellants. Also represented by
 ANDREW D. LOCKTON, EDWARD F. MCHALE, McHale &
 Slavin, P.A., Palm Beach Gardens, FL. Plaintiff-appellant
 Telebrands Corporation also represented by LORI DING,
 Baker Botts LLP; DAVID SMART STONE, Stone & Magnanini
 LLP, Berkeley Heights, NJ.

    MEGAN FREELAND RAYMOND, Groombridge, Wu,
 Baughman & Stone LLP, Washington, DC, argued for
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 2                 BLUE GENTIAN, LLC   v. TRISTAR PRODUCTS, INC.



 defendant-appellee. Also represented by JON STEVEN
 BAUGHMAN, SAURABH GUPTA.
                 ______________________

         Before PROST, CHEN, and STARK, Circuit Judges.
 PROST, Circuit Judge.
     Blue Gentian, LLC, National Express, Inc., and Tele-
 brands Corp. (collectively, “Blue Gentian”) sued Tristar
 Products, Inc. (“Tristar”) for infringement of U.S. Patent
 Nos. 8,291,941 (“the ’941 patent”), 8,291,942 (“the ’942 pa-
 tent”), 8,479,776 (“the ’776 patent”), 8,757,213 (“the ’213
 patent”), D722,681 (“the ’681 design patent”), and
 D724,186 (“the ’186 design patent”). Tristar counter-
 claimed to correct inventorship of all six patents. After an
 evidentiary hearing, the district court determined that a
 nonparty, Gary Ragner, should have been a named co-in-
 ventor on all asserted patents. Accordingly, the district
 court entered judgment on the inventorship counterclaim
 in Tristar’s favor and ordered correction of the patents un-
 der 

. Blue Gentian appeals. We affirm for
 the reasons outlined below.
                         BACKGROUND
                               I
    Blue Gentian owns all the asserted patents. 1 Michael
 Berardi was the sole named inventor on each patent. The



     1   Mr. Berardi is Blue Gentian’s principal. National
 Express had an exclusive license when this litigation be-
 gan, which has since been assigned to Telebrands. See
 Statement in Support of Mot. to Substitute, Blue Gentian,
 LLC v. Tristar Prods., Inc., 1:13-cv-01758 (D.N.J. May 19,
 2017), ECF No. 271-1; Ord. Denying Without Prejudice
 Mot. to Substitute and Joining Telebrands as Party, Blue
 Gentian, (D.N.J. June 19, 2017), ECF No. 289.
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 utility patents generally relate to an expandable hose. In
 turn, the design patents claim “[t]he ornamental design for
 an expandable hose [assembly], as shown and described.”
 ’681 design patent claim 1; ’186 design patent claim 1.
      An exemplary independent claim from the ’941 patent
 is reproduced below:
    1. A hose comprising:
    a flexible elongated outer tube constructed from a
    fabric material having a first end and a second end,
    an interior of said outer tube being substantially
    hollow;
    a flexible elongated inner tube having a first end
    and a second end, an interior of said inner tube be-
    ing substantially hollow, said inner tube being
    formed of an elastic material;
    a first coupler secured to said first end of said inner
    and said outer tubes;
    a second coupler secured to said second end of said
    inner and said outer tubes with the inner and outer
    tubes unsecured to each other between first and sec-
    ond ends; and
    said first coupler fluidly coupling said hose to a
    source of pressurized fluid, said second coupler cou-
    pling said hose to a fluid flow restrictor,
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 4                BLUE GENTIAN, LLC   v. TRISTAR PRODUCTS, INC.



     whereby said fluid flow restrictor creates an in-
     crease in fluid pressure between said first coupler
     and said second coupler within said hose, said in-
     crease in fluid pressure expands said elongated in-
     ner tube longitudinally along a length of said inner
     tube and laterally across a width of said inner tube
     thereby substantially increasing a length of said
     hose to an expanded condition and said hose con-
     tracting to a substantially decreased or relaxed
     length when there is a decrease in fluid pressure
     between said first coupler and said second coupler.
 ’941 patent claim 1 (emphasis added).
     Figure 1 of the ’941 patent is reproduced below:




 ’941 patent Fig. 1.
      The specification explains that “inner tube 14 is formed
 from a material that is elastic” and “outer tube 12 is formed
 from a non-elastic, relatively soft, bendable, tubular web-
 bing material,” preferably “braided or woven nylon, polyes-
 ter, or polypropylene.” ’941 patent col. 7 ll. 27–44. It also
 explains that the hose “includes a female coupler 18 at a
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 BLUE GENTIAN, LLC   v. TRISTAR PRODUCTS, INC.                 5



 first end and a male coupler 16 at a second end,” 

 at
 col. 7 ll. 48–49, where “[t]he outer tube 12 is unattached,
 unconnected, unbonded, and unsecured to the elastic inner
 tube 14 along the entire length of the inner tube 14 be-
 tween the first end and the second end,” 

 at col. 8 ll. 8–
 11.
                               II
     A single meeting, held on August 23, 2011, is central to
 the district court’s inventorship holding. And the district
 court’s factfindings about that meeting are key to the chal-
 lenges Blue Gentian raises on appeal.
     In 2011, Ragner Technology Corporation (“Ragner
 Tech.”) was seeking investors to bring its MicroHose prod-
 uct, an expandable hose, to market. Mr. Ragner, founder
 of Ragner Tech., and several others met with Mr. Berardi,
 the named inventor of the patents at issue, in Mr. Berardi’s
 home for that purpose. Blue Gentian v. Tristar Prods.,
 No. 13-1758, 

, at *10–11
 (D.N.J. Aug. 12, 2021) (“Inventorship Order”).
     Mr. Ragner has a B.S. in physics and an M.S. in aero-
 space engineering. J.A. 5501–02. Prior to the meeting,
 Mr. Ragner had designed many expandable hose proto-
 types. J.A. 5596; J.A. 9798–853. He was also the named
 co-inventor on issued 

 (“the ’527
 patent”) as well as 

 (“the ’836 pa-
 tent”), which at the time was filed but unpublished. Both
 patents generally relate to expandable hoses.
     Mr. Berardi has a degree in sociology. J.A. 6481:22–24.
 At the time of the meeting, he had no experience designing
 or building hoses. J.A. 6483:13–15. He testified that he
 was familiar with elastic bands based on his experience
 working in a hardware store decades earlier.
 J.A 6459:19–6460:6. Prior to the meeting, Mr. Berardi
 watched a video demonstrating the MicroHose.
 J.A. 6440:4–11; J.A. 7942 (video). He testified that after
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 6                BLUE GENTIAN, LLC   v. TRISTAR PRODUCTS, INC.



 seeing that video, but before the meeting, he came up with
 the idea for his expandable hose while at the gym.
 J.A. 6389:6–13. He testified that he “wonder[ed] what
 would happen if [he] put water through” a resistance band,
 J.A. 6385:10–18, but that he did not start building this
 hose at that time because “it was just . . . a nebulous con-
 cept,” J.A. 6389:14–24. Before the meeting, Mr. Berardi
 also reviewed a MicroHose business plan. J.A. 6451:2–12;
 J.A. 7417; J.A. 7432.
     Six other individuals attended the August 23, 2011
 meeting, and three of them testified during the inventor-
 ship hearing: Cheryl Berardi (Mr. Berardi’s wife), Marga-
 ret Combs (former Ragner Tech. CEO and current equity
 partner), and Robert de Rochemont (current CEO of Rag-
 ner Tech. and co-inventor of the ’527 and ’836 patents). In-
 ventorship Order, 

, at
 *10–11, *42–44.
     During the meeting, a document that detailed the man-
 ufacturing process for the MicroHose and showed its inner
 components was displayed.          J.A. 9430; J.A. 9563;
 J.A. 6410:15–21; J.A. 6411:21–23; J.A. 5655:18–5656:4.
 This document showed an inner “TPU Elastomer” layer
 and a reinforcement layer made of polyester yarn.
 J.A. 9430.
     Additionally, Mr. Ragner demonstrated a prototype of
 the MicroHose during the meeting. J.A. 5674:20–5677:8;
 J.A. 6297:6–8; J.A. 6427:12–17. Mr. Berardi testified that
 he “might have picked it up and, you know, squirted it
 around.” J.A. 6429:17–19. This prototype of the Mi-
 croHose had a vinyl inner tube for water to flow through, a
 wire coil spring for biasing (i.e., to provide a force to return
 the hose to a retracted state after expanding), and a yarn
 valley cord attached to the outside of the hose.
 J.A. 5675:1–5676:7. The version of the MicroHose that
 Ragner Tech. intended to market included a full fabric
 cover instead of the valley cord. J.A. 5556:23–5557:10.
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 BLUE GENTIAN, LLC   v. TRISTAR PRODUCTS, INC.                 7



     Mr. Ragner testified that during the meeting
 Mr. Berardi “asked whether [h]e could replace . . . the wire
 spring with elastic” and Mr. Ragner responded by saying
 that you could and by explaining that his “first two proto-
 types had a surgical tubing in them for the retracting
 force.” J.A. 5668:7–15; J.A. 5681:24–5682:5. He also testi-
 fied about the configuration of what the parties refer to as
 “prototype 2.” Mr. Berardi testified that this discussion of
 replacing the spring with elastic never occurred.
 J.A. 6423:17–25. But he did testify that Mr. Ragner “might
 have mentioned elastomer” at the meeting. J.A. 6459:5–6.
 Margaret Combs and Robert de Rochemont testified that
 they did not hear this conversation—Ms. Combs because
 she was seated too far away, J.A. 6111:7–15, and Mr. de
 Rochemont because he has hearing loss, J.A. 6202:19–24.
 Mrs. Berardi testified that she did not hear this conversa-
 tion either, J.A. 6293:3–15, but she also testified that she
 wasn’t paying as much attention as others present and pe-
 riodically left the room while the meeting continued,
 J.A. 6312:20–25; J.A. 6314:25–6315:16.
      Within hours after the meeting, Mr. Berardi went to
 Home Depot to buy supplies to build a hose prototype.
 J.A. 6458:14–17. The very next day, Mr. Berardi tested his
 first prototype. J.A. 10069 (video). Like Ragner Tech.’s
 prototype 2, Mr. Berardi’s initial prototype had an inner
 elastic tube to provide a biasing force and an outer tube
 that water ran through. J.A. 7944 (video 00:21–1:29); cf.
 J.A. 5686:12–25.
     Mr. Berardi filed his first patent application for an ex-
 pandable hose in November 2011, less than three months
 after the meeting. That application issued as the ’941 pa-
 tent, with Mr. Berardi listed as the sole inventor. Blue
 Gentian sued Tristar, licensee of Mr. Ragner’s ’836 and
 ’527 patents, for infringement in 2012—asserting the ’941
 patent, three related utility patents, and two of
 Mr. Berardi’s design patents. Tristar counterclaimed to
 correct inventorship.
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 8                BLUE GENTIAN, LLC   v. TRISTAR PRODUCTS, INC.



     After an evidentiary hearing, the district court con-
 cluded that Mr. Ragner should have been a named inventor
 on all of the asserted patents. Inventorship Order, 

, at *48–49. The district court en-
 tered final judgment on the inventorship claims under Fed-
 eral Rule of Civil Procedure 54(b). We have jurisdiction
 under 

(a)(1).
                         DISCUSSION
                               I
     Under 

, a district court may order cor-
 rection of inventorship when it determines that an inventor
 has been erroneously omitted from a patent. “All inven-
 tors, even those who contribute to only one claim or one
 aspect of one claim of a patent, must be listed on that pa-
 tent.” Vapor Point LLC v. Moorhead, 

,
 1348–49 (Fed. Cir. 2016). The named inventors are pre-
 sumed correct, and the party seeking correction of inven-
 torship must show by clear and convincing evidence that a
 joint inventor should have been listed. Eli Lilly & Co. v.
 Aradigm Corp., 

 (Fed. Cir. 2004).
     An alleged joint inventor’s testimony standing alone is
 insufficient to establish inventorship by clear and convinc-
 ing evidence. Ethicon, Inc. v. U.S. Surgical Corp., 

 (Fed. Cir. 1998). “Thus, an alleged co-inventor
 must supply evidence to corroborate his testimony.” 

 “Corroborating evidence may take many forms,” including
 “contemporaneous documents” or physical evidence, “[c]ir-
 cumstantial evidence,” and “oral testimony of someone
 other than the alleged inventor.” Id.; see also Sandt Tech.,
 Ltd. v. Resco Metal & Plastics Corp., 

,
 1350–51 (Fed. Cir. 2001). To determine whether testimony
 has been sufficiently corroborated, a “rule of reason” test is
 applied where “all pertinent evidence is examined in order
 to determine whether the inventor’s story is credible.”
 Sandt Tech., 

 (cleaned up). A court’s con-
 clusion about corroboration under this “rule of reason”
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 BLUE GENTIAN, LLC   v. TRISTAR PRODUCTS, INC.                 9



 analysis is a factfinding, which we review for clear error.
 Fleming v. Escort Inc., 

 (Fed. Cir.
 2014).
     An alleged joint inventor must show that he contrib-
 uted significantly to the conception—the definite and per-
 manent idea of the invention—or reduction to practice of at
 least one claim. Dana-Farber Cancer Inst., Inc. v. Ono
 Pharm. Co., 

 (Fed. Cir. 2020). And that
 these contributions arose from “some element of joint be-
 havior, such as collaboration or working under common di-
 rection” with the other inventor(s). Kimberly-Clark Corp.
 v. Procter & Gamble Distrib. Co., Inc., 

 (Fed. Cir. 1992).
      Inventorship is a question of law based on underlying
 facts. In re VerHoef, 

 (Fed. Cir. 2018).
 As we have noted, “[t]he determination of whether a person
 is a joint inventor is fact specific, and no bright-line stand-
 ard will suffice in every case.” Fina Oil & Chem. Co. v.
 Ewen, 

 (Fed. Cir. 1997); see also In re
 Jolley, 

 (Fed. Cir. 2002) (“[T]he concep-
 tion inquiry is fact-intensive . . . .”). We review the district
 court’s overall inventorship determination de novo, and the
 court’s underlying factfindings for clear error. Dana-Far-
 ber, 

.
     Blue Gentian alleges error in the district court’s deter-
 minations related to Mr. Ragner’s contribution to concep-
 tion, corroboration of his testimony, and collaboration
 between Mr. Ragner and Mr. Berardi. We address each
 contention of error in turn.
                                II
     First, we address Blue Gentian’s arguments related to
 contribution. The district court found that Mr. Ragner con-
 veyed three key elements of the hose to Mr. Berardi at the
 meeting: “(1) inner and outer tubes attached only at the
 ends, (2) a fabric outer tube, and (3) an elastic inner tube
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 10              BLUE GENTIAN, LLC   v. TRISTAR PRODUCTS, INC.



 that can provide force to retract the hose without a metal
 spring.” Inventorship Order, 

, at *33–34. Further, the district court found that
 these key elements amounted to a significant contribution
 “to the conception of at least one claim in each of the six
 asserted Berardi patents.” 

.
     Blue Gentian makes several arguments about the con-
 tribution determination. First, it argues that the district
 court erred because it did not construe the claims before
 finding a contribution. Second, it argues that the district
 court’s analysis of the contributed elements was not suffi-
 ciently tied to specific claims. Relatedly, Blue Gentian ar-
 gues that the three elements can’t amount to a
 contribution, let alone a significant one, because they
 aren’t the same elements reflected in the claims. As out-
 lined below, we reject each of these arguments.
                              A
     As for claim construction, Blue Gentian has not identi-
 fied a dispute about claim scope that is material, or even
 relates to, inventorship. Instead, Blue Gentian seems to
 argue that claim construction is always simply a threshold
 requirement—disputed terms or not. This argument is
 without merit.
      Before the district court, Blue Gentian argued that
 “[t]he inventorship of a patent can only be ‘corrected’ after
 a court construes the subject matter of each claim at issue.”
 J.A. 11246 (citing Trovan, Ltd. v. Sokymat SA, 

 (Fed. Cir. 2002)). It also stated that the terms
 “flexible elongated inner[/outer] tube” would require con-
 struction but did not propose a construction or explain how
 the terms’ meaning related to inventorship. Id.; see also
 J.A. 4584. Here, Blue Gentian still does not explain how
 the construction of “flexible elongated inner[/outer] tube,”
 or any other claim term, would have impacted the district
 court’s inventorship analysis or otherwise relates to the
 three contributed elements.
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 BLUE GENTIAN, LLC   v. TRISTAR PRODUCTS, INC.               11



     This court’s statement in Trovan that “an inventorship
 analysis, like an infringement or invalidity analysis, begins
 as a first step with a construction of each asserted claim to
 determine the subject matter encompassed thereby,” 

, does not establish a different requirement for
 construing claims in inventorship cases. As in other con-
 texts, when a fundamental dispute about claim scope
 arises, the district court may need to resolve it before it can
 evaluate inventorship. But “[w]here a district court has re-
 solved the questions about claim scope that were raised by
 the parties, it is under no obligation to address other po-
 tential ambiguities that have no bearing on the operative
 scope of the claim.” GPNE Corp. v. Apple Inc., 

 (Fed. Cir. 2016). In other words, the court is
 not required to prospectively address hypothetical claim-
 construction disputes. That is as true for inventorship
 analyses as it is for invalidity and infringement analyses.
 See, e.g., Simio, LLC v. FlexSim Software Prods., Inc., 

 (Fed. Cir. 2020) (finding “no error in the
 district court’s determining ineligibility without first con-
 ducting claim construction” where patentee “ha[d] not ex-
 plained how it might benefit from any particular term’s
 construction under an Alice § 101 analysis”).
     Blue Gentian’s insistence that claim construction was
 a prerequisite to an inventorship hearing, without more,
 did not present a dispute about claim scope. And since Blue
 Gentian did not otherwise present a material dispute about
 claim meaning, the district court did not err by making its
 inventorship determination without engaging in claim con-
 struction.
                               B
     Next, we turn to Blue Gentian’s arguments that the
 district court’s analysis of the contributed elements was
 not sufficiently tied to specific claims and that those ele-
 ments don’t amount to a contribution. The district court
 properly determined that the three key elements were a
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 12               BLUE GENTIAN, LLC   v. TRISTAR PRODUCTS, INC.



 significant contribution to the conception of at least one
 claim of each asserted patent. And, to the extent the dis-
 trict court should have provided a more detailed claim-by-
 claim comparison of Mr. Ragner’s contributions, any error
 in this regard was harmless. 2
      The district court determined that Mr. Ragner contrib-
 uted “(1) inner and outer tubes attached only at the ends,
 (2) a fabric outer tube, and (3) an elastic inner tube that
 can provide force to retract the hose without a metal
 spring.” Inventorship Order, 

, at *33–34. The court noted that “[i]t was not dis-
 puted that each of [the] four asserted utility patents has
 one or more claims that require at least these three ele-
 ments.” 

. As for the design patents, the district
 court found that by disclosing the three hose elements
 Mr. Ragner had “conveyed to Berardi a hose with the
 ‘crumpled’ aspect depicted in Berardi’s two design patent
 claims, which Berardi himself admitted is the result of how
 the hose is made.” 

 We agree with the district court’s
 conclusion that these three elements, taken together, were
 a significant contribution to at least one claim of each as-
 serted patent.
     For starters, we agree with Tristar that the three key
 elements are plainly reflected in the utility patents’ claim
 language. For example, claim 1 of the ’941 patent recites
 “a flexible elongated outer tube constructed from a fabric
 material . . . a flexible elongated inner tube . . . said inner
 tube being formed of an elastic material . . . with the inner
 and outer tubes unsecured to each other between first and


      2   The district court’s mention of the XHose, a com-
 mercial embodiment of the asserted patents, in its analysis
 was likewise harmless. Read in context, the opinion over-
 all reflects that the court understood that the inventorship
 analysis required an assessment of Mr. Ragner’s contribu-
 tion to the claims.
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 BLUE GENTIAN, LLC   v. TRISTAR PRODUCTS, INC.               13



 second ends.” ʼ941 patent claim 1. Similarly, claim 1 of the
 ’942 patent recites in relevant part “[a] hose assembly com-
 prising: an outer tube assembly formed from a soft non-
 elastic based control material housing an inner tube mem-
 ber constructed from an elastic based material . . . said
 outer tube assembly is unattached from said inner tube
 member between said first and said second coupler.” Claim
 15 of the ’213 patent recites “a flexible non-elastic elon-
 gated outer tube” and “a flexible elastic elongated inner
 tube” with “said inner and outer tubes being unattached,
 unbonded, unconnected and unsecured to each other except
 at the couplers” where the couplers are secured at the ends
 of the tubes. And claim 11 of the ’776 patent recites a
 “method of transporting water” by “providing a garden
 hose” with “an expandable elastic based hollow inner tube
 member” and “a soft non elastic bendable elongated outer
 tube member” with “said inner tube member and said outer
 tube member being secured to each other only at said first
 and said second ends and unsecured to each other between
 said first and said second ends forming a hose assembly.”
 The claims of each utility patent thus reflect the three key
 elements contributed by Mr. Ragner.
     Second, these are the very elements Blue Gentian has
 used to distinguish the invention of the asserted patents
 from the prior art. For example, during prosecution the
 “fabric outer tube” and the tubes’ “attach[ment] only at the
 ends” elements were used to overcome a rejection. The ’941
 patent was initially rejected based on the ’527 patent,
 J.A. 11532, which is entitled “pressure-actuated linearly
 retractable and extendible hose,” and for which Mr. Ragner
 is the named inventor, J.A. 7266 (capitalization normal-
 ized). 3 In an interview related to this rejection, the



     3  All of the asserted patents are in the same family.
 The ’941 patent was the first to issue and the other
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 14               BLUE GENTIAN, LLC   v. TRISTAR PRODUCTS, INC.



 patentee relied “mainly [on] the fact that the inner and
 outer layers of the [’527 patent] hose are bonded together
 and that the outer layer is [a] plastic material, wherein the
 present invention’s outer layer is formed of a fabric mate-
 rial” to distinguish the ’527 patent from the ’941 patent’s
 claims. J.A. 11532. These distinguishing features were
 then added as limitations to overcome the rejection.
 J.A. 11535; J.A. 11559. Further, at the district court, Blue
 Gentian again pointed to these two features along with the
 springless feature to distinguish the asserted patents from
 the ’527 patent. See J.A. 4305 (arguing that “Mr. Berardi
 successfully distinguished his inventions over the prior art
 ’527 patent, including by” pointing to the attached-only-at-
 the-ends and fabric-outer-tube features); J.A. 9526 (in re-
 sponse to invalidity contentions, arguing that unlike the
 asserted patents, the ’527 patent does not disclose inner
 and outer tubes secured only at the ends, a non-elastic
 outer tube, or retraction without a metal spring).
     Key features that the patent owner itself acknowledges
 distinguish the invention of the asserted patents from the
 prior art are necessarily tied to the claims. Likewise, it fol-
 lows that contributing such materially distinguishing fea-
 tures “is not insignificant in quality, when th[e]
 contribution is measured against the dimension of the full




 asserted patents all claim priority from it. Statements
 made by the patentee during prosecution of a patent can be
 relevant to other patents in the same family—particularly
 where, as here, added limitations are carried forward into
 the claims of the subsequently issued patents in the family.
 Cf. Verizon Servs. Corp. v. Vonage Holdings Corp., 

, 1306 (Fed. Cir. 2007) (“We have held that a state-
 ment made by the patentee during prosecution history of a
 patent in the same family as the patent-in-suit can operate
 as a disclaimer.”).
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 BLUE GENTIAN, LLC   v. TRISTAR PRODUCTS, INC.                15



 invention.” Pannu v. Iolab Corp., 

 (Fed.
 Cir. 1998).
     As for the design patents, we agree with the district
 court that Mr. Ragner’s three-element contribution applies
 to those patents as well. 4 “We apply the same standard of
 inventorship to design patents that we require for utility
 patents.” Hoop v. Hoop, 

 (Fed. Cir.
 2002). And, once a design is conceived, slight differences
 in appearance from the original do not amount to a new
 and separate design conception. 

 By conveying the
 three key elements, Mr. Ragner also conveyed “a hose with
 the [resultant] ‘crumpled’ aspect depicted” in the design pa-
 tents’ claims, Inventorship Order, 

, at *34, and contributed to the conception or reduc-
 tion to practice of the claimed designs in the design pa-
 tents. When Mr. Berardi was asked how he came up with
 the “idea of the fabric cover looking like” it did in the design
 patents, he responded “[c]ome up with the idea?
 That’s . . . the way the hose looks. And I mean, after the
 prototypes were made, that’s the way it looks as a garden
 hose.” J.A. 7903:20–7904:9. In other words, Mr. Berardi
 admitted that the resulting form of the fabric cover in the
 design patents turned on the elements used to construct
 his prototypes—a garden hose configuration that
 Mr. Berardi only developed based on the three hose ele-
 ments Mr. Ragner disclosed to him. And no one disputes
 that those three elements necessarily contribute to the pa-
 tented designs’ “crumpled” appearance.                Moreover,
 Mr. Berardi’s testimony provided no indication that the
 hose shown in his design patents included any design ele-
 ment independent of his focus on constructing a functional,
 retractable hose. As a result, the district court correctly




     4   The issue of the validity of the design patents was
 not before the district court and is not before us.
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 16               BLUE GENTIAN, LLC   v. TRISTAR PRODUCTS, INC.



 determined that Mr. Ragner was a significant contributor
 to those patents as well.
     In sum, the district court correctly concluded that
 Mr. Ragner contributed significantly to the conception of at
 least one claim of each asserted patent.
                               C
     In addition to asserting that the district court’s analy-
 sis was deficient, Blue Gentian makes several overlapping
 arguments about Mr. Ragner’s contribution to specific ele-
 ments and their significance to the claims. We also reject
 these arguments.
     Blue Gentian parses each element (or sub-element) of
 Mr. Ragner’s contribution and argues that it is not the
 same element claimed, was already present in the prior art,
 or was already conceived of by Mr. Berardi prior to the Au-
 gust 2011 meeting. Blue Gentian reiterates the same or
 similar arguments as both a reason that there wasn’t a con-
 tribution and a reason that any contribution was insignifi-
 cant. Although Blue Gentian dedicated many pages to
 these arguments in its opening brief, its reply brief did not
 respond to Tristar’s argument that the three elements “are
 plainly reflected in the claims,” Appellee’s Br. 24, or Tris-
 tar’s detailed arguments as to why Blue Gentian had not
 demonstrated that the district court’s factual findings were
 clearly erroneous.
     Initially, we reject Blue Gentian’s arguments that
 Mr. Ragner’s contributions were mere explanations of the
 state of the art because these arguments depend on sepa-
 rating out the three contributed elements (sometimes even
 further parsing them into sub-elements) and then attack-
 ing the district court’s findings as to each individually. The
 proper lens requires considering the elements in combina-
 tion, not in isolation. Likewise, it is the significance of
 Mr. Ragner’s overall contribution that matters for deter-
 mining inventorship, not the significance of certain
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 BLUE GENTIAN, LLC   v. TRISTAR PRODUCTS, INC.               17



 elements standing alone. Perhaps unsurprisingly (consid-
 ering the prosecution history and validity arguments dis-
 cussed above), Blue Gentian does not argue that this
 combination of elements was in the prior art. Nor does it
 argue that the contribution of all three elements together
 is insignificant.
      Similarly, we reject Blue Gentian’s arguments about
 Mr. Berardi’s prior conception because Blue Gentian does
 not point to evidence that he conceived of all three contrib-
 uted elements before the August 2011 meeting.
 Mr. Berardi testified that he generally “wonder[ed] what
 would happen if [he] put water” through an exercise re-
 sistance band. J.A. 6385:14–15. And while Blue Gentian
 argues that some exercise bands reflect the three elements,
 Appellants’ Br. 42, Mr. Berardi’s testimony clarifies that
 prior to the meeting he “didn’t know, you know, how [he]
 was going to make it or anything like that,”
 J.A. 6385:16–17. In sum, Mr. Berardi pondering whether
 it was possible to run water through an exercise band, after
 watching a video of the expandable MicroHose,
 J.A. 6387:1–5, is not a prior conception of a hose with
 “(1) inner and outer tubes attached only at the ends, (2) a
 fabric outer tube, and (3) an elastic inner tube that can pro-
 vide force to retract the hose without a metal spring.”
     Finally, while Blue Gentian attempts to frame its re-
 maining arguments that the elements Mr. Ragner dis-
 closed aren’t the same as what’s claimed as relating to a
 proper analysis of the claims themselves, these arguments
 really boil down to a challenge to the district court’s factual
 findings about what precisely was disclosed at the meet-
 ing—not what the claims require. Because Blue Gentian
 has not shown that the district court’s factfindings were
 clearly erroneous, we reject these arguments as well.
     For example, the district court found that Mr. Ragner
 contributed “an elastic inner tube that can provide force to
 retract the hose without a metal spring.” There was
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 18               BLUE GENTIAN, LLC   v. TRISTAR PRODUCTS, INC.



 evidence that (1) the process document shown at the meet-
 ing labeled the inner tube a “TPU Elastomer,” J.A. 9430;
 (2) the MicroHose prototype demonstrated at the meeting
 had an inner vinyl elastic tube that expanded when water
 flowed through it, J.A. 5675:1–5676:7; and (3) Mr. Ragner
 testified that he described his own prototype that used
 elastic as a biasing force and told Mr. Berardi that elastic
 could      replace       the      spring,      J.A. 5668:7–15;
 J.A. 5681:24–5682:5. Blue Gentian has not shown clear er-
 ror in the district court’s finding that the elastic inner hose
 tubes shown or discussed at the meeting were actually
 “elastic.” Nor has it shown clear error in the finding that
 Mr. Ragner’s discussion of prototype 2 and his explanation
 that an elastic tube could provide a biasing force conveyed
 the feature of an elastic tube providing retraction without
 a spring. See generally Nilssen v. Osram Sylvania, Inc.,
 

 (Fed. Cir. 2007) (“Under the clear error
 standard, the court’s findings will not be overturned in the
 absence of a definite and firm conviction that a mistake has
 been made.” (cleaned up)).
      As for the fabric outer tube that is connected to the in-
 ner tube only at the ends, the record includes: evidence that
 (1) the process document shown at the meeting showed a
 “polyester yarn” being added as a “reinforcement” layer,
 J.A. 9430; (2) the MicroHose that was demonstrated at the
 meeting had a yarn valley cord attached only at the ends,
 J.A. 5675:1–5676:7; (3) the full version of the MicroHose
 had a fabric cover (instead of a valley cord) that was only
 attached at the ends, J.A. 5556:23–5557:10, 5558:4–14;
 (4) testimony and a prototype instructions document indi-
 cated that it was typical to inform potential investors that
 the demonstrated prototype was missing the final version’s
 fabric cover, J.A. 7947; J.A. 6196:19–23; J.A. 5678:21–24,
 and Mr. Berardi testified that he was told that “the outer
 material” wasn’t what would “be used on the actual prod-
 uct,” J.A. 6428:12–6429:6; and (5) the MicroHose business
 plan that was sent to Mr. Berardi discussed a “knitted
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 BLUE GENTIAN, LLC   v. TRISTAR PRODUCTS, INC.               19



 reinforcement” to go over the interior plastic layer,
 J.A. 7432. Blue Gentian has not shown that factfindings
 related to these elements were clearly erroneous.
                               III
      Next, on the issue of corroboration, the district court
 found, based on “all pertinent evidence,” that “Ragner’s tes-
 timony is adequately corroborated both by physical and cir-
 cumstantial evidence.” Inventorship Order, 

, at *46–47. In reaching this conclusion, the
 district court considered Mr. Ragner’s ’836 patent and
 Mr. Berardi’s first prototype, including its similarity to
 Mr. Ragner’s prototype 2, particularly corroborative. Spe-
 cifically, the court emphasized that since “these exhibits
 are physical evidence created at the time of conception or
 reduction to practice, there is no risk of litigation-inspired
 fabrication or exaggeration.” 

. The district court
 also thoroughly examined how other testimony about the
 August 2011 meeting compared to Mr. Ragner’s account.
 

 at *41–46.
     Whether an alleged co-inventor’s account of inventor-
 ship is corroborated is a fact-intensive inquiry, governed by
 a rule-of-reason test. And we review the district court’s
 finding for clear error. Fleming, 

.
     In Blue Gentian’s view, the district court’s corrobora-
 tion analysis was flawed because it required corroboration
 only that Mr. Ragner conceived of the three key elements,
 without also requiring corroboration that he communicated
 them to Mr. Berardi. Further, it argues that the record
 does not support a corroboration finding. We disagree on
 both counts. The district court properly engaged in a rule-
 of-reason analysis aimed at determining whether Mr. Rag-
 ner’s story was credible overall. And considering the evi-
 dence as a whole, Blue Gentian has not shown clear error
 in the district court’s finding that Mr. Ragner’s account
 was corroborated.
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 20               BLUE GENTIAN, LLC   v. TRISTAR PRODUCTS, INC.



     On the first point, we see no flaw in the way the district
 court analyzed corroboration. The district court properly
 evaluated whether Mr. Ragner’s account, including both
 what he knew about expandable hoses going into the meet-
 ing and what he conveyed to Mr. Berardi at the meeting,
 was corroborated. See Ethicon, 

. Blue
 Gentian does not point to any case that indicates that such
 an analysis is flawed.
      For example, Blue Gentian relies on Price v. Symsek’s
 statement that “the person attacking the patent must es-
 tablish prior conception of the claimed subject matter and
 communication of the conception to the adverse claimant.”
 

 (Fed. Cir. 1993). Price is unhelpful
 here for several reasons. First, that case did not make a
 determination on corroboration; it simply remanded based
 on the Board’s application of an improperly high burden of
 proof. 

 at 1194–95. Additionally, a claim of derivation—
 the two elements of which are prior conception and commu-
 nication—was at issue there. 

. Here, in con-
 trast, the focus of the co-inventorship analysis is on
 contributions to conception and collaboration, making the
 absence of a specific call-out to the word communication in
 the district court’s opinion unsurprising. And, finally, even
 if the statement in Price were fully apt, it does not preclude
 an analysis of corroboration that considers conception and
 communication together. Indeed, the same evidence can be
 relevant to both. For example, in Davis v. Reddy, another
 derivation case Blue Gentian relies on, the court was “un-
 persuaded by Reddy’s uncorroborated testimony concern-
 ing what he disclosed at the meeting” where there was
 insufficient evidence that he had even conceived of what he
 claimed to have disclosed. 

 (CCPA 1980).
 An inventor can’t communicate something they haven’t
 conceived of yet. The corollary here is that the strength of
 documentary evidence showing Mr. Ragner’s familiarity
 with the three hose elements before the meeting lends cred-
 ibility to his account of conveying those ideas to
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 BLUE GENTIAN, LLC   v. TRISTAR PRODUCTS, INC.               21



 Mr. Berardi at a meeting centered around discussing and
 presenting on an expandable hose.
     Blue Gentian attempts to cast doubt on the corrobora-
 tive power of the ’836 patent, the prototype, and other wit-
 ness testimony individually. But these arguments ignore
 that corroboration is based on evaluation of the evidence as
 a whole. Fleming, 

 (explaining that the
 corroboration requirement “is a flexible, rule-of-reason de-
 mand for independent evidence that, as a whole, makes
 credible the testimony of the purported prior inventor”).
 No single piece of evidence alone needed to establish that
 Mr. Ragner’s account of inventorship was credible. 

     Considering the evidence as a whole, Blue Gentian has
 not demonstrated clear error. “Corroborating evidence
 may take many forms.” Ethicon, 

. “Docu-
 mentary or physical evidence that is made contemporane-
 ously with the inventive process provides the most reliable
 proof that the inventor’s testimony has been corroborated.”
 Sandt Tech., 264 F.3d at 1350–51. However, “[c]ircum-
 stantial evidence about the inventive process, alone, may
 also corroborate.” Id. at 1351. The district court drew rea-
 sonable inferences from the circumstantial evidence here.
 And we agree that Mr. Berardi’s first prototype, physical
 evidence created within a day of the meeting, provided a
 strong indication that Mr. Ragner’s story was credible.
                               IV
     With regard to collaboration, the district court found
 that there was sufficient collaboration between
 Mr. Berardi and Mr. Ragner based on the information ex-
 changed at the meeting. The opinion noted several indica-
 tions of collaboration (i.e., open communication related to
 the invention): that Mr. Berardi was shown detailed
 graphics and photographs containing confidential infor-
 mation about the MicroHose, that he held and used a pro-
 totype of the MicroHose, and that Mr. Ragner provided
 verbal explanations of alternative designs. Inventorship
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 22              BLUE GENTIAN, LLC   v. TRISTAR PRODUCTS, INC.



 Order, 

, at *28–29. Further,
 the district court credited Margaret Combs’s (meeting at-
 tendee, former Ragner Tech. CEO, and current equity part-
 ner) testimony that Mr. Berardi had agreed to sign an NDA
 and found that this was unfavorable to Blue Gentian’s po-
 sition. 

 at *29–30.
      Blue Gentian argues that the district court erred in
 finding that Mr. Ragner and Mr. Berardi collaborated. Its
 argument appears to boil down to a contention that
 Mr. Ragner’s contributions needed to be provided with the
 intent to invent the hose that was ultimately claimed. Spe-
 cifically, in Blue Gentian’s view, it is significant that
 Mr. Ragner attended the meeting to procure investment for
 a different hose, not design an alternative to it. We disa-
 gree.
     “People may be joint inventors even though they do not
 physically work on the invention together or at the same
 time, and even though each does not make the same type
 or amount of contribution.” Falana v. Kent State Univ., 

 (Fed. Cir. 2012). “The interplay between
 conception and collaboration requires that each co-inventor
 engage with the other co-inventors to contribute to a joint
 conception,” Vanderbilt Univ. v. ICOS Corp., 

 (Fed. Cir. 2010), not that each co-inventor inde-
 pendently conceives of the entire invention ultimately
 claimed. Since Mr. Ragner did not need to conceive of the
 entire invention, he certainly did not need to be intent on
 inventing the full invention ultimately claimed before he
 started collaborating.
     And while it’s true that co-inventors cannot be “com-
 pletely ignorant of what [the] other has done,” Kimberly-
 Clark, 

, we have never required that collab-
 oration involve the unity of vision that Blue Gentian ar-
 gues for. Here, the August 2011 meeting involved the
 requisite “element of joint behavior, such as collaboration
 or working under common direction, one inventor seeing a
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 BLUE GENTIAN, LLC   v. TRISTAR PRODUCTS, INC.               23



 relevant report and building upon it or hearing another’s
 suggestion at a meeting.”       

    Mr. Ragner showed
 Mr. Berardi confidential information about hoses he had
 designed, discussed technical details about how he planned
 to manufacture his hose, and discussed alternative ways to
 build an expandable hose. Mr. Berardi built off of those
 contributions and immediately began building prototypes
 of the expandable hose eventually claimed in the asserted
 patents.
                          CONCLUSION
     We have considered Blue Gentian’s remaining argu-
 ments and find them unpersuasive. For the foregoing rea-
 sons, we affirm.
                         AFFIRMED