NOTE: This disposition is nonprecedential.

United States Court of Appeals 

for the Federal Circuit ______________________

SANDBOX LOGISTICS LLC, OREN 

TECHNOLOGIES, LLC,

Plaintiffs-Appellants

v.

PROPPANT EXPRESS INVESTMENTS LLC, 

PROPPANT EXPRESS SOLUTIONS LLC,

Defendants-Appellees

______________________

2019-1684

______________________

Appeal from the United States District Court for the 

Southern District of Texas in No. 4:17-cv-00589, United 

States District Judge George C. Hanks, Jr.

______________________

Decided: May 18, 2020 

______________________

JOHN C. O'QUINN, Kirkland & Ellis LLP, Washington, 

DC, for plaintiffs-appellants. Also represented by CALVIN 

ALEXANDER SHANK, JASON M. WILCOX; GIANNI CUTRI, Chicago, IL. 

 JONATHAN S. FRANKLIN, Norton Rose Fulbright US 

LLP, Washington, DC, for defendants-appellees. Also represented by STEPHANIE DEBROW, Austin, TX; MARK 

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FRANCIS EBERHARD, CHARLES BRUCE WALKER, JR., Houston, TX. 

 ______________________

Before LOURIE, WALLACH, and HUGHES, Circuit Judges. 

WALLACH, Circuit Judge. 

Appellants SandBox Logistics LLC and Oren Technologies, LLC (together, “SandBox”) sued Appellees Proppant 

Express Investments LLC and Proppant Express Solutions 

LLC (together, “PropX”) in the U.S. District Court for the 

Southern District of Texas (“District Court”) alleging infringement of claims 2 and 13 of U.S. Patent No. 9,296,518 

(“the ’518 patent”), claims 6 and 17 of U.S. Patent 

No. 9,403,626 (“the ’626 patent”), claims 1, 3, 7, 8, 16, 18, 

19, and 21–23 of U.S. Patent No. 9,440,785 (“the ’785 patent”), and claims 4 and 7 of U.S. Patent No. 9,511,929 (“the 

’929 patent”) (collectively, “the Asserted Claims”).1 After a 

Markman hearing, the District Court issued an opinion, 

construing the parties’ disputed claim terms. See Sandbox

Logistics LLC v. Grit Energy Sols. LLC, Nos. 3:16-CV-12, 

4:17-CV-589, 2018 WL 3344773, at *2–17 (S.D. Tex. July 9, 

2018) (Opinion). Thereafter, SandBox and PropX stipulated to non-infringement of the Asserted Claims by

PropX’s accused products (“the Accused Products”), and the 

District Court entered a final judgment in favor of PropX.

See J.A. 1–4 (Final Judgment). 

SandBox appeals. We have jurisdiction pursuant to 28 

U.S.C. § 1295(a)(1). We affirm. 

1 SandBox also sued Liberty Oilfield Services LLC, 

J.A. 115, which is not a party to this appeal. 

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BACKGROUND 

I. The ’518, ’626, and ’929 Patents 

Entitled “Proppant Storage Vessel and Assembly 

Thereof,” the ’518, ’626, and ’929 patents share a common 

specification that “relates to storage containers” for proppant and “[m]ore particularly, . . . to storage container assemblies whereby a product in one container can flow to an 

interior volume of a lower container.” ’518 patent col. 1 

ll. 34–37.2 The ’518, ’626, and ’929 patents explain that 

“[p]roppant is a material, such as grains of sand, ceramic, 

or other particulates” used during hydraulic fracturing (or 

“fracking”) to “prevent . . . fractures from closing[.]” Id.

col. 1 ll. 53–54.3 The ’518, ’626, and ’929 patents disclose

“a proppant storage vessel . . . compris[ing] a container 

having a first end wall, a second end wall, a first side wall[,]

and a second side wall.” Id. col. 3 ll. 20–22; see id. col. 4 

l. 48 (“Each of the containers is [an] ocean freight container.”). “The container also has a top wall and a bottom 

wall” and “[a] hatch . . . formed on the bottom wall” which 

“is movable between an open position and a closed position.” Id. col. 3 ll. 22–26. An “inclined surface” extends 

from each wall to the bottom hatch, id. col. 3 ll. 26–32, “to 

assure that the proppant contained within the [container]

is suitably funneled toward the bottom hatch[,]” id. col. 7 

ll. 18–21. The container may include “support brace[s]” to 

“structurally enhance the strength of the container . . . so 

as to . . . withstand the weight of the proppant that is 

2 Because the ’518, ’626, and ’929 patents share a 

common specification, we cite to only the ’518 patent for 

ease of reference, unless otherwise specified. 3 “Hydraulic fracturing is the propagation of fractions in a rock layer caused by the presence of pressurized 

fluid[,] . . . made in order to release petroleum, natural gas, 

coal seam gas, or other substances for extraction.” ’518 patent col. 1 ll. 36–41. 

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contained therein.” Id. col. 7 ll. 24–44. The ’518, ’626, and 

’929 patents disclose that the containers may be “vertically 

aligned in a stacked orientation[,]” id. col. 6 l. 65, so that 

proppant “in one container can flow to an interior volume 

of a lower container[,]” id. col. 1 ll. 36–37, and ultimately 

onto a “portable conveyer . . . placed below the bottom 

hatch” of the lowermost container, id. col. 6 ll. 7–8; see id.

col. 4 ll. 2–6 (“The bottom hatch of the second container is 

aligned with the opening of the first container such that a 

proppant in the first container can flow through the [bottom] hatch thereof into the interior volume of the first container.”); see also id., Figs. 1, 2. 

II. The ’785 Patent 

Entitled “Method of Delivering, Storing, Unloading, 

and Using Proppant at a Well Site,” the ’785 patent “relates 

to storage containers” and “[m]ore particularly, . . . to proppant discharge systems wherein proppant can be discharged from the storage container. Additionally, the [’785 

patent] relates to a process for providing proppant to a well

site by the transport and delivery of the proppant containers.” ’785 patent col. 1 ll. 16–21. The ’785 patent discloses

“a container for the transport and storage of proppant . . . 

compris[ing] a box having a bottom, a pair of side walls[,] a 

pair of end walls[,] and a top.” Id. col. 7 ll. 53–55; see id.

col. 10 ll. 32–36 (“[T]he container . . . is a ten-foot [International Organization for Standardization] container.”). An 

“inlet [is] formed at or adjacent to the top” of the box and 

an “outlet” is formed “at the bottom.” Id. col. 7 ll. 56–57. A 

“ramp” extends from each wall to the outlet, id. col. 7 ll. 60–

64, and “serve[s] to funnel[] the proppant that is retained 

within . . . the container . . . toward the outlet[,]” id. col. 10 

ll. 44–46. The container also includes an “exterior frame” 

that “provides structural support for the container . . . and 

generally surrounds the exterior of the container” with “a 

plurality of vertical bars that extend so as to form a cagelike configuration around the walls[.]” Id. col. 9 l. 64, 

col. 10 ll. 15–20; see id., Figs. 1, 2. 

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III. Procedural History 

In February 2017, SandBox sued PropX in the District 

Court, alleging infringement of the Asserted Claims. 

J.A. 115. In March 2018, the District Court held a Markman hearing. J.A. 125–26. In July 2018, the District Court 

issued its Opinion, construing, among other terms, “[t]he 

term ‘bottom’ in the ’518, ’626, and ’929 patents[,]” Sandbox 

Logistics, 2018 WL 3344773, at *4, and “[t]he term ‘structural support members’ in the [’]785 patent[,]” id. at *15.4 

Thereafter, SandBox and PropX stipulated to non-infringement of the Asserted Claims by the Accused Products and 

the District Court entered the Final Judgment in favor of

PropX. See J.A. 1–4. 

DISCUSSION 

I. Standard of Review and Legal Standard 

“The proper construction of a patent’s claims is an issue 

of Federal Circuit law[.]” Powell v. Home Depot U.S.A., 

Inc., 663 F.3d 1221, 1228 (Fed. Cir. 2011) (citation omitted). “[C]laim construction must begin with the words of 

the claims themselves.” Amgen Inc. v. Hoechst Marion 

Roussel, Inc., 457 F.3d 1293, 1301 (Fed. Cir. 2006) (citation 

omitted). “[W]ords of a claim are generally given their ordinary and customary meaning,” which is “the meaning 

4 The District Court also construed other terms that 

SandBox raises on appeal. See Sandbox Logistics, 2018 WL 

3344773, at *2–6 (construing the terms “adjacent” and 

“top” of the ’626 and ’929 patents), *8–10 (construing the 

term “support braces” of the ’518, ’626, and ’929 patents 

and the term “structural supports” of the ’626 and ’929 patents); see also Appellant’s Br. 15. We need not address the 

District Court’s construction of these other terms, however, 

as we may resolve the issues on appeal by addressing the 

terms “bottom” and “structural support members” alone. 

See infra notes 11, 12. 

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that the term would have to a person of ordinary skill in 

the art [(‘PHOSITA’)] in question at the time of the invention[.]” Phillips v. AWH Corp., 415 F.3d 1303, 1312–13 

(Fed. Cir. 2005) (en banc) (internal quotation marks and 

citations omitted). “The words used in the claims are interpreted in light of the intrinsic evidence of record, including the written description, the drawings, and the 

prosecution history[.]” Teleflex, Inc. v. Ficosa N. Am. Corp., 

299 F.3d 1313, 1324 (Fed. Cir. 2002) (citation omitted). 

The PHOSITA “is deemed to read the claim term not only 

in the context of the particular claim in which the disputed 

term appears, but in the context of the entire patent, including the specification.” Phillips, 415 F.3d at 1313.5 The 

prosecution history may also be looked to in order to supply 

additional evidence of a claim term’s intended meaning. 

See Home Diagnostics, Inc. v. Lifescan, Inc., 381 F.3d 1352, 

1356 (Fed. Cir. 2004).6 While courts may also consider extrinsic evidence in claim construction, “such evidence is 

generally of less significance than the intrinsic record.” WiLAN, Inc. v. Apple Inc., 811 F.3d 455, 462 (Fed. Cir. 2016) 

(citation omitted).7 “[T]he ultimate construction of a claim 

term is a legal question reviewed de novo, [while] underlying factual determinations made by the district court are 

reviewed for clear error.” Enzo Biochem Inc. v. Applera 

5 The specification “includes both the written description and the claims” of a patent. In re Packard, 751 

F.3d 1307, 1320 n.11 (Fed. Cir. 2014). 6 A patent’s prosecution history “consists of the complete record of the proceedings before the [U.S. Patent and 

Trademark Office (‘USPTO’)],” providing “evidence of how 

the [US]PTO and the inventor understood the patent.” 

Phillips, 415 F.3d at 1317 (citation omitted). 7 “[E]xtrinsic evidence . . . consists of all evidence external to the patent and prosecution history[.]” Phillips,

415 F.3d at 1317 (internal quotation marks and citation 

omitted). 

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Corp., 780 F.3d 1149, 1153 (Fed. Cir. 2015) (citation omitted). 

II. The District Court Properly Construed the Term

“Bottom” as Recited in the ’518, ’626, and ’929 Patents 

The District Court concluded that a PHOSITA would 

understand the “term ‘bottom’ in the ’518, ’626, and ’929

patents . . . to mean ‘bottom wall[.]’” Sandbox Logistics, 

2018 WL 3344773, at *4. Specifically, the District Court 

“conclude[d] from its review of the specification and prosecution history that a [PHOSITA] would understand that 

the [containers] used to construct the temporary proppant 

storage facility are modified standard intermodal shipping 

containers, which have . . . bottom walls.” Id. at *6. Thus, 

the District Court “conclude[d] that a [PHOSITA] would 

understand the term[] ‘bottom’ . . . to mean ‘bottom wall[.]’” 

Id. SandBox contends, however, that the District Court’s 

construction “must be set aside” as “[i]ts rationale . . . relied entirely on its erroneous understanding that the 

claims require an ‘ocean freight container’ and on continuing to read in limitations from the specification.” Appellant’s Br. 68. We disagree with SandBox. 

The District Court properly construed the term “bottom” as recited in the ’518, ’626, and ’929 patents. Consistent with claim construction principles, we look first to 

the language of the Asserted Claims, followed by the language of the specification and prosecution history. See

Phillips, 415 F.3d at 1314–17. Independent claim 1 of the 

’518 patent, from which asserted claims 2 and 13 depend,

recites, in relevant part, “a container comprising[:] a cavity; sidewalls that define a lateral periphery of the cavity; . . . inclined surfaces that define a lower periphery of 

the cavity . . . ; a bottom; . . . [and] a hatch positioned 

closely adjacent to the bottom[.]” ’518 patent col. 8 l. 57–

col. 9 l. 3. Similarly, independent claim 1 of the ’626 patent, 

from which asserted claim 6 depends, recites a “container 

comprising: a top; a bottom, having an outlet formed 

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therein; sidewalls coupled to the top and bottom, so as to 

define an interior volume of the container . . . ; and a hatch 

positioned proximate the outlet[.]” ’626 patent col. 8 l. 64–

col. 9 l. 25. Independent claim 13 of the ’626 patent, from 

which asserted claim 17 depends, likewise recites a “first 

container having . . . a first outlet in a first bottom” and a 

“second container . . . having a second outlet in a second 

bottom[.]” Id. col. 11 ll. 4–7, 13–17. Finally, independent 

claim 1 of the ’929 patent, from which asserted claim 4 depends, and independent claim 7 of the ’929 patent, both recite, in relevant part, limitations materially identical to 

those recited in the ’626 patent. See ’929 patent col. 9 

ll. 14–45, col. 10 ll. 1–52. 

While the claims do not shed much light on the appropriate construction of “bottom,” the claims invariably require that the “bottom” has an “outlet” or “hatch” formed 

therein. Additionally, the juxtaposition of the terms “bottom” and “sidewalls” throughout the claims indicates that 

“bottom” may refer to something other than a wall. See 

Phillips, 415 F.3d at 1314 (“Differences among claims

can . . . be a useful guide in understanding the meaning of 

particular claim terms.”); cf. Fuji Photo Film Co. v. Int’l 

Trade Comm’n, 386 F.3d 1095, 1104–05 (Fed. Cir. 2004) 

(“The fact that . . . [a] limitation was included in the first 

step and omitted from the second and third steps provides 

strong textual support for [the] argument that the claim 

should be construed to distinguish between the first step 

and the other two.”). Thus, while not dispositive, the 

claims seem to suggest that “bottom” may refer to a group 

of structures other than walls alone. 

Turning to the broader specification, see Trs. of Columbia Univ. v. Symantec Corp., 811 F.3d 1359, 1363 (Fed. 

Cir. 2016) (“[T]he specification is always highly relevant to 

the claim construction analysis and is, in fact, the single 

best guide to the meaning of a disputed term.” (internal 

quotation marks, emphasis, and citation omitted)), the

’518, ’626, and ’929 patents disclose three embodiments of 

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the “present invention” each of which explicitly requires 

containers with a “bottom wall”: (1) “[t]he present invention is a proppant storage vessel that comprises a container 

having a first end wall, a second end wall, a first side wall[,]

and a second side wall” as well as “a top wall and a bottom 

wall which serve to define an interior volume therein[,]” 

’518 patent col. 3 ll. 20–24; (2) “[t]he present invention is 

also a proppant storage assembly that comprises a first 

container” that “has a bottom wall [with] a bottom hatch 

affixed thereto” and a “second container” that “has [a] bottom hatch formed on a bottom wall thereof[,]” id. col. 3 

l. 62–col. 4 l. 2; and (3) “[i]n an alternative embodiment of 

the present invention, the first container has the first side 

wall, a second side wall, a first end wall[,] and second end 

wall hingedly mounted to the bottom wall thereof[,]” id.

col. 4 ll. 49–52; see id., Abstract (“A proppant storage vessel 

has a container having . . . a bottom wall.”). Thus, the specification makes clear that the invention of the ’518, ’626, 

and ’929 patents includes a “bottom wall.” See Poly-Am., 

L.P. v. API Indus., Inc., 839 F.3d 1131, 1136 (Fed. 

Cir. 2016) (“While disavowal must be clear and unequivocal, it need not be explicit. For example, an inventor may 

disavow claims lacking a particular feature when the specification describes ‘the present invention’ as having that 

feature.” (internal citations omitted)).8 Indeed, each 

8 While the ’518, ’626, and ’929 patents provide that 

the embodiments of the “present invention” are “not intended, in any way, to limit the scope of the present invention[,]” ’518 col. 4 ll. 55–60; see id. col. 8 ll. 48–53 (“The 

foregoing disclosure and description of the invention is illustrative and explanatory thereof.”), such boilerplate language, without more, is not sufficient to overcome the 

explicit description of the “present invention,” see D Three 

Enters., LLC v. SunModo Corp., 890 F.3d 1042, 1051 (Fed. 

Cir. 2018) (“[B]oilerplate language at the end of the . . . 

specification is not sufficient to show adequate disclosure 

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embodiment disclosed in the ’518, ’626, and ’929 patents 

includes a “bottom wall.” See ’518 patent col. 5 ll. 18–24 

(“[T]he preferred embodiment of the present invention . . . 

includes a first container . . . having . . . a bottom wall[.]”), 

col. 8 ll. 18–23 (“[A]n alternative embodiment of the container . . . of the present invention . . . includes . . . end 

walls . . . and . . . side walls . . . extending upwardly from a 

bottom wall[.]”). Thus, while the claims may suggest that 

“bottom” refers to something other than a wall, the broader 

specification makes clear that “bottom” refers to a “bottom 

wall.” Cf. Edwards Lifesciences LLC v. Cook Inc., 582 F.3d 

1322, 1332 (Fed. Cir. 2009) (“[C]laim differentiation is a 

rule of thumb that does not trump the clear import of the 

specification.”).9 

The prosecution history supports the conclusion that 

“bottom” refers to a “bottom wall.” During prosecution of 

the ’518 patent, an examiner twice rejected claims for

“omitting essential elements[,]” viz., “[t]he bottom wall on 

of the actual combinations and attachments used in the . . . 

[c]laims.”); see also IP Innovation, L.L.C. v. Ecollege.com, 

156 F. App’x 317, 321 (Fed. Cir. 2005) (explaining that 

“common boiler plate” language did not effectively disclose

an alternative embodiment to support a broader construction of the claims at issue than the embodiment described 

in the specification as the “present invention”). 

9 Moreover, were the “bottom” something other than 

a wall as SandBox argues, e.g., “a mesh, an open frame, or 

some other structure[,]” Appellant’s Br. 69, the “bottom”—

against which “[t]he bottom hatch resides . . . when in the 

closed position[,]” ’518 patent col. 3 ll. 59–61—would allow 

proppant to escape the container, see Medrad, Inc. v. MRI 

Devices Corp., 401 F.3d 1313, 1319 (Fed. Cir. 2005) (“It 

is . . . entirely proper to consider the functions of an invention in seeking to determine the meaning of particular 

claim language.”). 

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which the hatch is mounted.” J.A. 1007 (March 2015 Office 

Action), 1063 (November 2014 Office Action) (the Examiner 

explaining that “[t]he only hatches disclosed are positioned 

on a flat bottom wall”).10 As the Examiner explained, he

“considered [the bottom wall] essential because the specification does not describe a means to connect the hatch to 

the container without the bottom wall.” J.A. 1007. Sandbox did not challenge the Examiner’s understanding; instead, in response, SandBox amended the claims of the ’518 

patent to recite a “bottom[,]” J.A. 575, with SandBox explaining that although the claims “were rejected on the basis [that] they lack essential elements[,]” the claims were 

“being amended to include a bottom, and that the hatch is 

positioned closely adjacent to the bottom[,]” J.A. 580. The 

Examiner allowed the ’518 patent, based at least in part on 

his understanding that the claims of the ’518 patent were 

amended to include a “bottom wall on which the hatch is 

mounted.” J.A. 1007; see J.A. 1025 (Notice of Allowability) 

(the Examiner explaining that the prior art “fails to teach 

or suggest . . . a bottom[] and a hatch closely adjacent to the 

bottom”). SandBox’s failure to challenge the Examiner’s

understanding amounts to a disclaimer. See Biogen Idec, 

Inc. v. GlaxoSmithKline LLC, 713 F.3d 1090, 1096 (Fed. 

Cir. 2013) (“If an applicant chooses, she can challenge an 

10 The prosecution history of the ’518 patent is relevant to the scope of the ’626 and ’929 patents, which matured from continuation applications of the ’518 patent. 

See ’626 patent, Front Page; ’929 patent, Front Page; see

also Augustine Med., Inc. v. Gaymar Indus., Inc., 181 F.3d 

1291, 1300 (Fed. Cir. 1999) (“[T]he prosecution history of a 

parent application may limit the scope of a later application using the same claim term[.]”); Jonsson v. Stanley 

Works, 903 F.2d 812, 818 (Fed. Cir. 1990) (explaining that 

the prosecution history of a parent application is relevant 

to understanding the scope of claims issuing in a continuation application). 

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examiner’s characterization in order to avoid any chance 

for disclaimer, but the applicants in this case did not directly challenge the examiner’s characterization.”); TorPharm, Inc. v. Ranbaxy Pharm., Inc., 336 F.3d 1322, 1330 

(Fed. Cir. 2003) (“[I]n ascertaining the scope of an issued 

patent, the public is entitled to equate an inventor’s acquiescence to the examiner’s narrow view of patentable subject matter with abandonment of the rest. Such 

acquiescence may be found where the patentee narrows his 

or her claims by amendment[.]” (internal citation omitted)). 

Thus, the prosecution history confirms that “bottom” refers 

to a “bottom wall.” Accordingly, the District Court properly 

construed the term “bottom” as recited in the ’518, ’626, and 

’929 patents.11 

11 Because every asserted claim of the ’518, ’626, and 

’929 patents requires a “bottom[,]” see ’518 patent col. 8 

l. 67 (independent claim 1, from which asserted claims 2 

and 13 depend); ’626 patent col. 8 l. 67 (independent 

claim 1, from which asserted claim 6 depends), col. 11 ll. 6–

7, 17 (independent claim 13, from which asserted claim 17 

depends); ’929 patent col. 9 l. 18 (independent claim 1, from 

which asserted claim 4 depends), col. 10 ll. 6, 28 (asserted 

independent claim 7), and because SandBox stipulated 

that the “Accused Products do not have a ‘bottom wall’ 

as . . . is required by the term ‘bottom[,]’” J.A. 2, we need 

not consider SandBox’s remaining arguments as to the District Court’s construction of other terms of the ’518, ’626, 

and ’929 patents to affirm the District Court’s Final Judgment of non-infringement as to those patents, see Advanced 

Steel Recovery, LLC v. X-Body Equip., Inc., 808 F.3d 1313, 

1321 (Fed. Cir. 2015) (“Because we affirm [the district 

court’s determination of] noninfringement, we do not reach 

[the defendant]’s alternative arguments for affirmance.”). 

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III. The District Court Properly Construed the Term 

“Structural Support Members” as Recited in the

’785 Patent

The District Court concluded that a PHOSITA “would 

understand the term ‘structural support members’ to refer 

to structural fortifications to the end walls and sidewalls of 

an existing ocean freight container that are placed between 

the container’s end frame members[.]” Sandbox Logistics, 

2018 WL 3344773, at *15. SandBox contends, however, 

that “nothing about the term ‘structural support members’ 

requires that the claims’ containers be ‘ocean freight containers.’” Appellant’s Br. 53. Additionally, SandBox argues that “‘structural support members’ does not refer 

solely to ‘structural fortifications to the end walls and sidewalls’ of a container, much less require adding supports to 

an existing ocean freight container.” Id. at 54. Rather, “the 

plain and ordinary meaning of ‘structural support members’ includes features in or of the wall itself[, ]e.g., a corrugated surface[].” Id. (emphasis omitted). We disagree 

with SandBox. 

The District Court properly construed the term “structural support members” as recited in the ’785 patent as 

“structural fortifications” provided on an “existing” container. Turning first to the language of the Asserted 

Claims, see Phillips, 415 F.3d at 1314, independent claim 1 

of the ’785 patent, from which asserted claims 3, 7, and 8 

depend, recites, in relevant part, “a plurality of proppant 

containers . . . each . . . having a closed and substantially 

rectangular upper proppant containing portion,” as well as 

“a pair of vertically-extending end walls and a pair of vertically-extending side walls defining the closed and substantially rectangular upper proppant containing portion,” 

and “a frame including a plurality of structural support 

members positioned to span the end walls and the sidewalls between end frame members to enhance support of 

the end walls and the side walls when the proppant container is full of fracking proppant[.]” ’785 patent col. 14 

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l. 65–col. 15 l. 31. Independent claim 16 of the ’785 patent, 

from which asserted claims 18, 19, and 21–23 depend, recites materially identical limitations. See id. col. 18 ll. 27–

64. That the “structural support members” are recited separately from the “end walls” and “side walls” implies that 

the “structural support members” are a structurally distinct component. See Becton, Dickinson & Co. v. Tyco 

Healthcare Grp., LP, 616 F.3d 1249, 1254 (Fed. Cir. 2010) 

(“Where a claim lists elements separately, the clear implication of the claim language is that those elements are distinct components of the patented invention.” (internal 

quotation marks, alteration, and citation omitted)); see 

HTC Corp. v. Cellular Commc’ns Equip., LLC, 701 F. App’x 

978, 982 (Fed. Cir. 2017) (“The strongest evidence for this 

separation is the claim language itself, which plainly recites two different structures . . . . The separate naming of 

two structures in the claim strongly implies that the named 

entities are not one and the same structure.”). Thus, the 

claim language supports the District Court’s construction. 

Turning to the broader specification, see Trs. of Columbia Univ., 811 F.3d at 1363, the ’785 patent discloses that 

a “frame . . . provides structural support for the container . . . and generally surrounds the exterior of the container. The frame is formed of a plurality of vertical bars 

that extend so as to form a cage-like configuration around 

the walls[.]” ’785 col. 10 ll. 15–19. As shown in Figures 1 

and 2 of the ’785 patent, the “vertical bars,” i.e., “structural 

support members,” of the disclosed frame are depicted as 

separate and distinct components vis-à-vis the walls, even 

extending beyond the walls to the bottom of the container. 

Id., Figs. 1 and 2. Indeed, each embodiment disclosed in 

the ’785 patent includes this configuration. Thus, as with 

independent claims 1 and 16, the broader specification supports the District Court’s construction. 

Finally, during prosecution of the ’785 patent, SandBox 

disclaimed the construction it now proposes, and limited 

the “structural support members” to a separate and 

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distinct component. Specifically, in response to an obviousness rejection over prior art, including U.S. Publication 

No. 2013/0206415 (“Sheesley”), SandBox distinguished

Sheesley by arguing that the “container . . . [of Sheesley] is 

formed from corrugated metal” in which “the corrugated 

metal structure is an integral part of the sidewalls used to 

form the structure of the container . . . . As such, the sidewalls do not include separate, distinct support members as 

recited by [the] independent [c]laims[.]” J.A. 1268–69; see

J.A. 1269 (“As shown in F[ig]. 9, the sidewalls are standalone components of the container . . . without any additional support members attached thereto.”). This is inconsistent with SandBox’s position on appeal, viz., that the 

same claim language “broadly encompasses fortifications 

made in the walls themselves, such as internal folds or corrugations that add strength.” Appellant’s Br. 3. SandBox

clearly disavowed this subject matter, and cannot be allowed to recapture it. See Omega Eng’g, Inc, v. Raytek 

Corp., 334 F.3d 1314, 1323 (Fed. Cir. 2003) (“The doctrine 

of prosecution disclaimer . . . preclud[es] patentees from recapturing through claim interpretation specific meanings 

disclaimed during prosecution.”); see also Aylus Networks, 

Inc. v. Apple Inc., 856 F.3d 1353, 1360 (Fed. Cir. 2017) (“Ultimately, the doctrine of prosecution disclaimer ensures 

that claims are not construed one way in order to obtain 

their allowance and in a different way against accused infringers.” (internal quotation marks and citation omitted)). 

Accordingly, the District Court properly construed the 

term “structural support members” as recited in the ’785 

patent as “structural fortifications” provided on an “existing” container.12 

12 Because SandBox “limit[ed] their infringement allegation pertaining to the term ‘structural support members’ in the ’785 patent to the horizontal corrugations in the 

walls of the Accused Products,” J.A. 3, and because 

Case: 19-1684 Document: 53 Page: 15 Filed: 05/18/2020
SANDBOX LOGISTICS LLC v. PROPPANT EXPRESS 

INVESTMENTS

16

CONCLUSION 

We have considered SandBox’s remaining arguments 

and find them unpersuasive. Accordingly, the Final Judgment of the U.S. District Court for the Southern District of 

Texas is 

AFFIRMED 

“structural support members” cannot include “corrugations 

in . . . walls” based on SandBox’s representations during 

prosecution of the ’785 patent, we need not consider SandBox’s remaining arguments as to the District Court’s construction of other terms of the ’785 patent to affirm the 

District Court’s Final Judgment of non-infringement as to 

that patent, see Advanced Steel, 808 F.3d at 1321. 

Case: 19-1684 Document: 53 Page: 16 Filed: 05/18/2020