Shamrock Building Materials, Inc. v. United States

United States Court of Appeals
for the Federal Circuit
______________________
SHAMROCK BUILDING MATERIALS, INC.,
Plaintiff-Appellant
v.
UNITED STATES,
Defendant-Appellee
______________________
2023-1648
______________________
Appeal from the United States Court of International
Trade in No. 1:20-cv-00074-TCS, Senior Judge Timothy C.
Stanceu.
______________________
Decided: October 23, 2024
______________________
PATRICK D. GILL, Sandler, Travis & Rosenberg, P.A.,
New York, NY, argued for plaintiff-appellant. Also
represented by DONALD CAMERON, JR., NICHOLAS DUFFEY,
MARY HODGINS, JULIE MENDOZA, BRADY MILLS, R. WILL
PLANERT, Morris Manning & Martin LLP, Washington, DC.
NICO GURIAN, Commercial Litigation Branch, Civil
Division, Department of Justice, New York, NY, argued for
defendant-appellee. Also represented by AIMEE LEE,
JUSTIN REINHART MILLER, MARCELLA POWELL, MATHIAS
RABINOVITCH; VALERIE SORENSEN-CLARK, International
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SHAMROCK BUILDING MATERIALS, INC. v. US 2
Trade Litigation, United States Customs and Border
Protection, New York, NY.
______________________
Before TARANTO, HUGHES, and CUNNINGHAM, Circuit
Judges.
TARANTO, Circuit Judge.
Shamrock Building Materials, Inc. imported into the
United States from Mexico steel tubing having a thin
interior coating mainly composed of epoxy, melamine, and
silicone additives. The United States Customs and Border
Protection (Customs) classified the conduit under heading
7306 of the Harmonized Tariff Schedule of the United
States (HTSUS), which covers “[o]ther tubes, pipes . . . of
iron or nonalloy steel.” Shamrock protested, urging
classification under heading 8547 of the HTSUS, which
covers “[e]lectrical conduit tubing . . . of base metal lined
with insulating material.” (Emphasis added.) Customs
rejected the protests. Shamrock filed an action in the
Court of International Trade (Trade Court), which granted
summary judgment to the United States, upholding the
classification under heading 7306. Shamrock Building
Materials, Inc. v. United States, 619 F. Supp. 3d 1337 (Ct.
Int’l Trade 2023) (Shamrock). On Shamrock’s appeal, we
now affirm.
I
A
Shamrock imports electrical metallic tubing and
intermediate metal conduit produced by Conduit S.A. de
C.V. (doing business as RYMCO) in Mexico. Id. at 1341;
J.A. 143. Both types of conduit are at issue here, and both
are hollow concentric tubes of steel, sold in ten-foot lengths,
though they have different wall thicknesses. Shamrock,
619 F. Supp. 3d at 1341. Pieces of the conduit can be
connected by threaded steel couplings “to form a ‘raceway’
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SHAMROCK BUILDING MATERIALS, INC. v. US 3
for the routing of electrical wiring” in commercial and
residential buildings “while protecting the wires within
from external forces.” Id.
The conduit is coated on the outside with zinc (which
helps prevent rust) and, what is central here, on the inside
with a compound that is composed principally of epoxy
resin, melamine resin, and silicone additives (other
ingredients not having been disclosed by the coating’s
manufacturer, Pinturas Diamex, S.A., which sold it to
RYMCO). See id.; J.A. 144 ¶¶ 2–3, 910:6–11, 941:3–42:9,
954:12–55:6, 1412 ¶¶ 2–3, 1591–92, 1803 ¶ 8, 1804 ¶ 11.
The interior coating, which was measured to be between 10
and 60 microns in thickness, functions at least in part to
facilitate the installation of electrical wires within the
conduit by protecting them from abrasion and tears
resulting from friction created when pulling wires through
the conduit. See Shamrock, 619 F. Supp. 3d at 1341; J.A.
1455 ¶ 7, 1803 ¶ 9. Shamrock has emphasized that
installation function in marketing. A brochure used to
advertise one of the conduits at issue states: “Smooth
interior coating insulates wall to provide easy installation
of wire.” J.A. 1589. It is undisputed, based on testing for
this case, that the coating also provides a nonzero amount
of resistance to electrical current flow. See Shamrock, 619
F. Supp. 3d at 1345.1 But the parties dispute the relevance
1 See id. at 1345 (“Plaintiff’s witness measured the
resistivity of the coating inside the conduit to be between
120 milliohms and 1.2 ohms, depending on the testing
method, and defendant’s witness measured the resistivity
as much less than that.”); id. at 1345 n.5 (“Using a two-
point test, plaintiff’s witness measured 0.2 ohms of
resistivity on uncoated pipe and between 0.7 and 1.2 ohms
of resistivity on the coated pipe. Using a four-point test,
plaintiff’s witness measured the resistivity of the uncoated
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SHAMROCK BUILDING MATERIALS, INC. v. US 4
of that resistance amount to the HTSUS classification
question in this case. They also dispute the relevance of
the facts, found by the Trade Court, that “[t]he parties are
unaware of any customers who purchased the conduit from
Shamrock specifically ‘because the interior coating
provides electrical insulation’” and that the above-noted
marketing brochure, while noting the benefit to
installation, “does not advertise the interior coating as
providing insulation from electrical current.” Id. at 1341,
1344.
B
Shamrock made 201 entries of conduit into the United
States between June and October 2018. Id. at 1339.
Between April and July 2019, Customs classified the
conduit under heading 7306 of the HTSUS, which is within
chapter 73 (“[a]rticles of iron or steel”) of the HTSUS, itself
within Section XV (including “ARTICLES OF BASE
METAL”). Id. at 1339, 1342–43. (There is no dispute here
about what HTSUS language is at issue, which is from the
2018 editions. Id. at 1340 n.2.) Specifically, Customs
classified the conduit, according to its wall thickness,
either under subheading 7306.30.1000, HTSUS, which
covers
[o]ther tubes, pipes, and hollow profiles . . . welded,
of circular cross section, of iron or nonalloy steel . . .
[h]aving a wall thickness of less than 1.65 mm
or under subheading 7306.30.5028, HTSUS, which covers
pipe to be 2.5 milliohms and the coated pipe to be 120
milliohms. Defendant’s witness measured the resistivity of
the lining to be between 3.419 and 14.043 milliohms.”)
(citations omitted). The Trade Court noted the absence of
any substantial evidence that the coating impedes heat
flow, at least in the intended use. Id. at 1345–46.
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SHAMROCK BUILDING MATERIALS, INC. v. US 5
[o]ther tubes, pipes and hollow profiles . . . welded,
of circular cross section, of iron or nonalloy steel . . .
[h]aving a wall thickness of 1.65 mm or more . . .
[w]ith an outside diameter not exceeding 114.3 mm
. . . [g]alvanized . . . [i]nternally coated or lined with
a non-electrically insulating material suitable for
use as electrical conduit (emphasis added).2
2 More fully, subheading 7306.30.1000 reads:
7306. Other tubes, pipes and hollow profiles (for
example, open seamed or welded, riveted, or similarly
closed), of iron or steel:
* * *
7306.30. Other, welded, of circular cross section, of iron
or nonalloy steel:
7306.30.1000. Having a wall thickness of less than
1.65mm.
Subheading 7306.30.5028 reads more fully:
7306. Other tubes, pipes and hollow profiles (for
example, open seamed or welded, riveted, or similarly
closed), of iron or steel:
* * *
7306.30. Other, welded, of circular cross section, of iron
or nonalloy steel:
* * *
7306.30.5028. Having a wall thickness of 1.65 mm or
more:
* * *
Other
* * *
Other:
With an outside diameter not exceeding 114.3 mm:
Galvanized:
* * *
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SHAMROCK BUILDING MATERIALS, INC. v. US 6
Those classifications produced a 25 percent import duty
because of the tariffs imposed on steel starting in 2018
under Section 232 of the Trade Expansion Act of 1962, as
amended, 19 U.S.C. § 1862—without which no duty would
have been assessed. See Shamrock, 619 F. Supp. 3d at
1343.
Shamrock timely filed protests before Customs under
19 U.S.C. § 1514, arguing that the conduit should have
been classified under heading 8547 of HTSUS, which is
within Chapter 85 (“[e]lectrical machinery and equipment
and parts thereof”), itself within Section XVI (including
“ELETRICAL EQUIPMENT; PARTS THEREOF”).
Shamrock, 619 F. Supp. 3d at 1339, 1343. Specifically,
Shamrock argued that the conduit should be classified
under subheading 8547.90.0020, which covers
[e]lectrical conduit tubing and joints therefor, of
base metal lined with insulating material . . .
[c]onduit tubing.3
Internally coated or lined with a non-electrically
insulating material, suitable for use as electrical
conduit.
3 More fully, subheading 8547.90.0020 reads:
8547. Insulating fittings for electrical machines,
appliances or equipment, being fittings wholly of
insulating material apart from any minor components
of metal (for example, threaded sockets) incorporated
during molding solely for the purposes of assembly,
other than insulators of heading 8546; electrical
conduit tubing and joints therefor, of base metal lined
with insulating material:
* * *
8547.90. Other
* * *
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SHAMROCK BUILDING MATERIALS, INC. v. US 7
That classification would have resulted in a duty of 4.6
percent or zero. See Shamrock, 619 F. Supp. 3d at 1343.4
Customs denied Shamrock’s protests, under 19 U.S.C.
§ 1515, on November 7 and December 9, 2019, affirming its
classification under heading 7306. Id. at 1339. Within the
time allowed by 28 U.S.C. § 2636(a), and invoking 28
U.S.C. § 1581(a), Shamrock sued the United States in the
Trade Court to challenge the protest denials (and hence the
classifications) by filing its summons on April 6, 2020 (then
following up with a complaint on May 20, 2020). See id. at
1340; J.A. 28–29; 28 U.S.C. § 2632(b) (suit to challenge
protest denial under 19 U.S.C. § 1515 initiated by filing
summons). Shamrock and the United States filed cross-
motions for summary judgment. See Shamrock, 619 F.
Supp. 3d at 1339–40. The parties disagreed about the
interpretation and applicability of heading 8547,
specifically subheading 8547.90.0020—which defined the
issue for decision, because there was and is no dispute that,
if heading 8547 is inapplicable, then Customs’
classification within heading 7306 must be approved.
The Trade Court held that heading 8547 does not apply.
Shamrock, 619 F. Supp. 3d at 1339–48. The court adopted
8547.90.0020. Electrical conduit tubing and joints
therefor, of base metal lined with insulating material:
Conduit tubing
4 At the relevant time, goods within subheading
8547.90.0020 were subject to a general (Column 1) duty of
4.6 percent but would enter free of duty if they qualified for
preferential treatment under the North American Free
Trade Agreement Implementation Act (NAFTA). Id. at
1343 (citing General Note 12, HTSUS). According to
Shamrock, Customs informed it on November 15, 2018,
that the conduit qualified for the preferential treatment.
See Complaint at 6–7 ¶¶ 36, 38, Shamrock, No. 1:20-cv-
00074 (ECF # 10, May 20, 2020).
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SHAMROCK BUILDING MATERIALS, INC. v. US 8
an interpretation of the phrase of heading 8547 that is in
dispute—“electrical conduit tubing . . . of base metal lined
with insulating material.” Id. at 1344–46. That phrase,
the court held, requires a level of impeding current flow (or
heat) to the metal tube that is viewed as significant in the
commercial context defined by the intended use to
surround electricity-conducting wiring. Id. at 1346 (“The
court interprets heading 8547, HTSUS in a common and
commercial context to describe electrical conduit that
performs an insulating function necessary or desirable for
electrical wiring in applications for which the conduit is
designed and for which it is marketed in commerce.”); id.
(“the insulating layer must function in a way that relates
to the ‘electrical conduit’ function, i.e., it must impede
electrical current or isolate the heat from the wire from the
inside surface of the steel conduit”).
Under that interpretation, the Trade Court ruled,
Shamrock’s conduit did not come within heading 8547. On
the factual matters relevant under the adopted
interpretation, Shamrock did not overcome the
presumption of correctness of Customs’ classification by
carrying its burden of proving the classification to be
incorrect. Id. at 1342, 1348. The court found that “the
uncontested facts are inconsistent with a finding that the
coating ‘insulates’ the interior wire so as to impede the
transfer of electrical current or heat when the conduit is
used for its intended purpose”; although “the coating inside
the subject conduit provides some measurable resistance
(or ‘resistivity’) to the flow of electric current when
compared to the same pipe when uncoated,” “the
uncontested facts also demonstrate that the degree of
resistivity is not significant in relation to the intended use
of the conduit.” Id. at 1345. “Notably,” the court explained,
Shamrock “does not contend that the coating provides
significant protection from current flow or heat, and the
brochure” promoting conduit at issue “does not make any
such claims.” Id. at 1345–46.
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SHAMROCK BUILDING MATERIALS, INC. v. US 9
Based on the interpretation of heading 8547 and the
facts found, the Trade Court held that Shamrock’s
electrical conduit “is not ‘electrical conduit . . . of base
metal lined with an insulating material’ within the
meaning of that term as used in the article description for
heading 8547, HTSUS.” Id. at 1346 (quoting heading 8547,
HTSUS). The conduit at issue “is instead described by the
terms of heading 7306.” Id. (quoting heading 7306,
HTSUS). The court granted summary judgment in favor of
the United States on March 13, 2023, and entered
judgment on that date. Id. at 1337, 1339, 1348; J.A. 1–2.
Shamrock timely appealed. This court has jurisdiction
under 28 U.S.C. § 1295(a)(5).
II
A
We review the Trade Court’s grant of summary
judgment without deference. CamelBak Products, LLC v.
United States, 649 F.3d 1361, 1364 (Fed. Cir. 2011). Proper
classification of goods under the HTSUS requires two
steps: “first ascertaining the meaning of specific terms in
the tariff provisions and then determining whether the
subject merchandise comes within the description of those
terms.” Victoria’s Secret Direct, LLC v. United States, 769
F.3d 1102, 1106 (Fed. Cir. 2014) (quoting Millenium
Lumber Distribution Ltd. v. United States, 558 F.3d 1326,
1328 (Fed. Cir. 2009)); see R.T. Foods, Inc. v. United States,
757 F.3d 1349, 1352 (Fed. Cir. 2014). The first step involves
an issue of law we decide de novo, the second an issue of
fact whose resolution by the Trade Court we review only for
clear error. Victoria’s Secret, 769 F.3d at 1106; see R.T.
Foods, 757 F.3d at 1352; Orlando Food Corp. v. United
States, 140 F.3d 1437, 1439 (Fed. Cir. 1998).
Under 28 U.S.C. § 2639(a)(1), the Customs
classification decision at issue here “is presumed to be
correct” and “[t]he burden of proving otherwise shall rest
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SHAMROCK BUILDING MATERIALS, INC. v. US 10
upon the party challenging such decision.” See, e.g.,
Universal Electronics Inc. v. United States, 112 F.3d 488,
491 (Fed. Cir. 1997); Millenium Lumber, 558 F.3d at 1328.
The statutory presumption of correctness applies only to
factual issues. See Goodman Manufacturing, L.P. v.
United States, 69 F.3d 505, 508 (Fed. Cir. 1995)
(presumption “not relevant” where there is no factual
dispute). It is a “procedural device that is designed to
allocate, between the two litigants to a lawsuit, the burden
of producing evidence in sufficient quantity. Specifically,
the importer must produce evidence (the burden of
production portion of the burden of proof) that
demonstrates by a preponderance (the burden of
persuasion portion of the burden of proof) that Customs’
classification decision is incorrect.” Universal Electronics,
112 F.3d at 492; see also, e.g., Timber Products Co. v. United
States, 515 F.3d 1213, 1219 (Fed. Cir. 2008); Libas, Ltd. v.
United States, 193 F.3d 1361, 1365 (Fed. Cir. 1999).
B
The HTSUS is composed of headings, each of which
“set[s] forth general categories of merchandise,” and “has
one or more subheadings” that “provide a more
particularized segregation of the goods within each
category.” E.g., Orlando Food Corp., 140 F.3d at 1439
(emphasis added); Schlumberger Technology Corp. v.
United States, 845 F.3d 1158, 1163 (Fed. Cir. 2017); Otter
Products, LLC v. United States, 834 F.3d 1369, 1375 (Fed.
Cir. 2016); Wilton Industries, Inc. v. United States, 741 F.3d
1263, 1266 (Fed. Cir. 2013); see also U.S. Int’l Trade
Comm., Preface to the 30th Edition: Guide to the HTS and
Statistical Reporting, at 2 n.5 (Jan. 1, 2018) (explaining
that a subheading “cover[s] a subset of the heading’s
product scope”); Sigma-Tau HealthScience, Inc. v. United
States, 838 F.3d 1272, 1280–81 (Fed. Cir. 2016) (relying on
this structural relationship).
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SHAMROCK BUILDING MATERIALS, INC. v. US 11
The headings and subheadings are enumerated in
chapters, each of which has its own section and chapter
notes. R.T. Foods, 757 F.3d at 1353. Congress also
prescribed, among other things, “General Rules of
Interpretation” (GRI) for HTSUS. Id. Classification
analysis begins with GRI 1, which states that “for legal
purposes, classification shall be determined according to
the terms of the headings and any relative section or
chapter notes.” See Orlando Food, 140 F.3d at 1440.
“Absent contrary legislative intent, HTSUS terms are to be
construed according to their common and commercial
meanings, which are presumed to be the same. A court
may rely upon its own understanding of the terms used and
may consult lexicographic and scientific authorities,
dictionaries, and other reliable information sources.” Carl
Zeiss, Inc. v. United States, 195 F.3d 1375, 1379 (Fed. Cir.
1999) (internal citation omitted). After consulting the
headings and relevant section or chapter notes, we may
also consult the relevant Explanatory Notes. Kahrs
International, Inc. v. United States, 713 F.3d 640, 644–45
(Fed. Cir. 2013) (citation omitted). In contrast to “section
or chapter notes,” which are binding, Explanatory Notes
“are not legally binding or dispositive,” but they often help
resolve an interpretive dispute because they “are generally
indicative of the proper interpretation of the various
HTSUS provisions.” Id.; see Sigma-Tau, 838 F.3d at 1280–
81. Other GRIs lay down other classification rules (such as
GRI 3’s preference for the specific over the general, see
Orlando Food, 140 F.3d at 1440–41), but the principles just
described control the decision in the present case.
III
The only question here is whether heading 8547
applies to the conduit at issue. The note to section XV,
where heading 7306 resides, excludes articles classified
under section XVI, where heading 8547 resides. HTSUS,
Section XV, Note 1(f) at XV-1 (“This section does not cover:
. . . [a]rticles of section XVI (machinery, mechanical
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SHAMROCK BUILDING MATERIALS, INC. v. US 12
appliances and electrical goods) . . . .”). It is not disputed
here that if heading 8547 applies to the conduit, heading
7306 does not apply and that, if heading 8547 does not
apply, heading 7306 does. See Shamrock, 619 F. Supp. 3d
at 1343–44.
In this case, the dispute before us reduces to a dispute
about the interpretation of heading 8547. We interpret the
key language of the heading as requiring commercially
significant insulation of the conduit against current flow
(and perhaps heat flow) from an electricity-conducting wire
inside the conduit, and we see no material difference
between that interpretation and the interpretation set
forth and applied in the Trade Court’s opinion. See, e.g.,
Shamrock, 619 F. Supp. 3d at 1346. Shamrock disputes
that interpretation, but if we adopt it, as we do, no further
issue needs to be decided for us to affirm the judgment
before us.
That is because, on appeal, Shamrock does not make a
procedural argument that, even under that interpretation,
the Trade Court erred in deciding the case on summary
judgment rather than proceeding to a trial. And it has not
shown any basis for setting aside the Trade Court’s
determination that Shamrock did not present evidence
that would allow a finding that the coating provided
commercially significant dampening of current or heat flow
between a conducting wire and the metal conduit. Indeed,
Shamrock admitted that it is “unaware of ‘any customers
that have stated’ that they purchase the electrical conduit
exclusively because of it[s] electrical insulating properties
rather than its protective insulating properties.” J.A. 1805
¶ 14. The only marketing brochure in the record mentions
an installation benefit and “[p]hysical and mechanical
protection,” but not in-use protection against current or
heat flow. J.A. 1589; see also id. (brochure noting that
conduit affirmatively provides “system grounding,” which
the government expert testified means that “the conduit
and interior coating must be a good conductor of
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SHAMROCK BUILDING MATERIALS, INC. v. US 13
electricity,” J.A. 1499 ¶ 28). Finally, even if litigation-
prompted testing could substitute for marketplace
evidence, the Trade Court determined that the testing here
could not be found to do so if the standard was one of
commercial significance, and Shamrock has not shown
error in that determination. See Shamrock, 619 F. Supp.
3d at 1345.
We therefore turn to the dispute about the correct
interpretation of heading 8547—specifically, about the
phrase, “electrical conduit tubing . . . of base metal lined
with insulating material.” We explain our conclusion about
the proper interpretation in steps.
First: We reject Shamrock’s suggestion that heading
8547 covers any lining that contains, among its
ingredients, materials (such as epoxy resins or silicone)
that standing alone are recognized as insulating materials.
The natural reading of “lined with insulating material” is
that the “lin[ing]” (considered as a unit) must be a
“material” that is “insulating.” Otherwise, in Shamrock’s
apparent view, the heading would cover a material that,
while containing insulating compounds, also contains
highly conducting material, for example, so that the lining
as a whole is anything but insulating. See J.A. 308
(testimony of Dr. Jeffrey T. Gotro, expert witness for
Shamrock, confirming that even materials that are
composed mostly of constituents with insulating
properties, like epoxy, can nonetheless be “conductive” and
“fail to insulate against electricity” when combined with
other materials, such as “metallic filler[s]”).
Second: The term “insulate” (in its several word forms)
can be used to cover protection of various kinds—e.g.,
against rust-causing oxygen, current or heat flow, sound,
and perhaps abrasion. But heading 8547, understood in
context, does not cover all kinds of “insulating.” The
“insulating” that counts for heading 8547 is best
understood to mean protection against the passage of
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SHAMROCK BUILDING MATERIALS, INC. v. US 14
current (and/or heat) from an electricity-conducting wire
through the lining to the metal tubing.
That understanding is immediately suggested by the
opening words of the heading 8547 phrase in dispute.
What is being lined is “electrical conduit tubing.” That
language, indicating an intended use, suggests that the
identified property of the lining be tied to the use—here, of
insulating electricity-conducting wires inside the conduit.
See Shamrock, 619 F. Supp. 3d at 1346. Moreover, the
parties agree that headings 8547 and 7306 create a
structural dichotomy: For the steel conduit at issue, if it
comes within heading 8547, it is outside heading 7306, and
vice versa. Appellant’s Br. at 7, 44; Appellee’s Br. at 17.
The fairest inference is that the “insulating” property of
heading 8547 is the property of being “electrically”
insulating.
That conclusion is confirmed by relevant explanatory
notes—which can be, and here are, persuasive, though they
are not binding. Explanatory Note 85.47 and Explanatory
Note 73.06 “draw a distinction between electrical conduit
tubing that is ‘insulated’ and electrical conduit tubing that
is ‘uninsulated,’” with the former covered by heading 8547
and the latter by heading 7306. Shamrock, 619 F. Supp. 3d
at 1345. The language used in the explanatory notes to
characterize the two headings—“insulated” versus
“uninsulated”—confirms that “insulating” in heading 8547
means electrically insulating (though the word
“electrically” is not used), because metal tubes lined or
coated with non-electrically insulating material fall within
heading 7306. Compare Explanatory Note 73.06
(excluding “[i]nsulated electrical conduit tubing (heading
85.47)” from heading 7306), with Explanatory Note 85.47
(explaining that “uninsulated metal tubing, often used for
the same purpose [i.e., permanent electrical installations],
is excluded” from heading 8547). See also Shamrock, 619
F. Supp. 3d at 1345. In addition, Explanatory Note 85.47
excludes “[m]etal tubing simply coated with varnish to
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SHAMROCK BUILDING MATERIALS, INC. v. US 15
prevent corrosion,” thus excluding one form of insulation,
namely from oxygen or other corrosive elements or
compounds.
Third: As to how to identify what is electrically
insulating within heading 8547, the most sensible
standard is one tied to the intended purpose of the
commercial product: the provision of a commercially
significant degree of electrical insulation when an
electricity-conducting wire is in use in the conduit. Both
parties view electrical resistance as an appropriate lens
through which to assess insulating properties. See J.A. 157
¶¶ 105–108, 858, 1223–24, 1496–97 ¶ 17, 1522. Shamrock
has suggested that any positive number in electrical-
resistance tests, no matter how close to zero, should suffice
for a lining to be electrically insulating, but it offers no
persuasive basis for such a conclusion. Resistance appears
in degrees, on a continuous scale, and a standard is needed
to identify how much is enough for a product to be
electrically insulating.
Compositional makeup affects a lining’s insulating
properties, as does thickness. See J.A. 318 (testimony of
Shamrock witness, Dr. Gotro); J.A. 1222 (testimony of
government expert, Dr. Athanasios Meliopoulos); J.A. 1592
(letter from Pinturas Diamex, S.A., manufacturer of the
coating material at issue here). But those facts do not
resolve how much resistance is required. The most
appropriate standard, we conclude, is what the commercial
marketplace deems significant when the product is used as
intended (when a conducting wire is in use in the conduit).
That interpretation fits the established preference for
“common and commercial meanings,” Carl Zeiss, 195 F.3d
at 1379, and aligns with our recognition that intended use
can identify meaning even of an eo nomine classification,
GRK Canada Ltd. v. United States, 761 F.3d 1354, 1358–
59 (Fed. Cir. 2014), and that “how the subject articles are
regarded in commerce” and “how the subject articles are
described in sales and marketing literature” can “guide the
Case: 23-1648 Document: 61 Page: 15 Filed: 10/23/2024

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SHAMROCK BUILDING MATERIALS, INC. v. US 16
court’s assessment of whether articles fall within the scope
of an eo nominee provision,” CamelBak, 649 F.3d at 1364–
65, 1368; Sigma-Tau, 838 F.3d at 1279. And it may be
implemented by facts from the marketplace, such as
promotions of the products at issue, including perhaps
comparisons to the amount of resistance provided by
products clearly outside heading 8547, such as metal
tubing simply coated with varnish to prevent corrosion or
coated with non-electrically insulating material covered by
heading 7306. Explanatory Note 85.47.
One final point: Shamrock cites several prior
administrative rulings by Customs, such as HQ 966525,
HQ 966526, Ruling N306508, Ruling N290590, and Ruling
NY I84073, that classify lined electrical conduit (or other
electrical products) in heading 8547 without speaking to
whether and how to assess the degree of the electrically
insulating property of the relevant lining material. See,
e.g., J.A. 1335–41, 1344–50, 1356–57, 1360, 1364. But the
cited rulings do not provide any analysis of how to interpret
“lined with insulating material” or determine what degree
of “insulating” function, compared to “non-electrically
insulating material[s],” is required. In this circumstance,
we do not find the earlier rulings to warrant deference
under Skidmore v. Swift & Co., 323 U.S. 134 (1944); see
also Loper Bright Enterprises v. Raimondo, 144 S. Ct. 2244,
2259, 2267 (2024), or otherwise to alter our conclusion.
CONCLUSION
For the foregoing reasons, we affirm the Court of
International Trade’s grant of summary judgment in favor
of the United States.
AFFIRMED
Case: 23-1648 Document: 61 Page: 16 Filed: 10/23/2024

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