UNITED STATES – ANTI-DUMPING MEASURES ON POLYETHYLENE RETAIL CARRIER BAGS FROM THAILAND
Document: Report of the Panel
Date: 22 January 2010
Document codes: WT/DS383/R
Complainant: Thailand
Respondent: U.S.
Third parties: Argentina, EU, Japan, South Korea, Taiwan
Dispute stage: Panel
Agreements cited: Art. 2.4.2  Anti-dumping

UNITED STATES – ANTI-DUMPING MEASURES ON
POLYETHYLENE RETAIL CARRIER BAGS FROM
THAILAND

Report of the Panel

I. INTRODUCTION
1.1 On 26 November 2008, the Government of th e Kingdom of Thailand ("Thailand") requested
consultations pursuant to Article XXIII:1 of the General Agreement on Tariffs and Trade 1994 (the
"GATT 1994"), Article 4 of the Understanding on Rules and Procedures Governing the Settlement of
Disputes (the "DSU"), and Articles 17.2, 17.3 and 17.4 of the Agreement on Implementation of Article
VI of the General Agreement on Tariffs and Trade 1994 (the "Anti-Dumping Agreement"), concerning
the United States' alleged application of the practice known as "zeroing" of negative dumping margins
in the United States' determination of certain marg ins of dumping in its anti-dumping investigation of
polyethylene retail carrier bags from Thailand. 1 Thailand and the United States held consultations in
Geneva on 28 January 2009, but failed to resolve th e dispute. At the Dispute Settlement Body (the
"DSB") meeting held on 20 March 2009, Thailand requested the establishment of a panel pursuant to
Article XXIII:1 of the GATT 1994, Articles 4 and 6 of the DSU, and Article 17.4 of the Anti-
Dumping Agreement.
2 At that meeting, the DSB established a panel pursuant to the request of
Thailand.
1.2 The Panel's terms of reference are the following:
"To examine, in the light of the relevant provisions of the covered agreements cited
by the parties to the dispute, the matter referred to the DSB by Thailand in document
 and to make such findings as will assist the DSB in making the
recommendations or in giving the rulings provided for in those agreements."
1.3 On 20 August 2009, the parties agreed to the following composition of the Panel:
Chairman: Mr. Alberto Juan Dumont

 Members: Ms Deborah Milstein
 Mr. Norman M. Harris

1.4 Argentina, the European Communities
3, Japan, Korea and Chinese Taipei reserved their rights
to participate in the Panel proceedings as third parties.
1.5 After consulting with the parties, and with the accord of the third parties, the Panel decided
not to hold any substantive meetings with the parties and/or third parties.4
II. FACTUAL ASPECTS
2.1 The measures at issue in this dispute are th e anti-dumping order imposed by the United States
on polyethylene retail carrier bags from Thailand (t he "Order") and the Final Determination (the

1 WT/DS383/1.
2 WT/DS383/2.
3 On 1 December 2009, the Treaty of Lisbon amendi ng the Treaty on Europe an Union and the Treaty
establishing the European Community (done at Lisbon, 13 December 2007) entered into force. On
29 November 2009, the WTO received a Verbal Note (WT/L/779) from the Council of the European Union and
the Commission of the European Communities stating that, by virtue of the Treaty of Lisbon, as of
1 December 2009, the European Union replaces and succeeds the European Community.
4 The parties submitted a joint procedural agreement providing, inter alia, that the parties should ask
the Panel to accept only one written submission per party, that the parties should ask the Panel to forego
meetings with the parties, that the United States woul d not contest Thailand's claim, that Thailand should not
ask the Panel to suggest ways in which the United States might implement the Panel's recommendations
pursuant to the second sentence of Article 19.1 of the DSU, and that the United States should implement the
Panel's recommendations using specified provisions of US law (WT/DS383/4).

"Final Determination") by the United States Depart ment of Commerce (the "USDOC"), as amended,
leading to that Order.
2.2 The United States published its notice of initia tion of its anti-dumping investigation of
polyethylene retail carrier bags from Thailand on 16 July 2003. The Final Determination in this
investigation was published on 18 June 2004, and an amended final determ ination was published by
the USDOC on 15 July 2004.
2.3 Following a final determination of injury by the United States International Trade
Commission, the United States issued an anti-dumpi ng duty order on imports of polyethylene retail
carrier bags from Thailand on 9 August 2004.
III. PARTIES' REQUESTS FOR FINDINGS AND RECOMMENDATIONS
A. T
HAILAND
3.1 Thailand claims that in its Final Determinati on, as amended, the USDOC used the "zeroing"
methodology to determine the final dumping margin s for individually investigated Thai exporters
subject to the Order whose margins of dumping were not based on total facts available. In particular,
Thailand claims that, in calculating the anti-dumping margins for the relevant exporters, the USDOC:
(i) identified different "models," i.e., types, of products based on the most relevant
product characteristics;
(ii) calculated weighted average prices in the United States and weighted average normal
values in the comparison market on a model- specific basis, for the entire period of
investigation;
(iii) compared the weighted average normal va lue of each model to the weighted average
United States price for that same model;
(iv) calculated the dumping margin for an exporter by summing up the amount of
dumping for each model and then dividing it by the aggregated United States price for
all models; and
(v) set to zero all negative margins on individual models before summing the total
amount of dumping for all models.
3.2 Thailand submits that through this method, the USDOC calculated margins of dumping and
collected anti-dumping duties in amounts that exceeded the actual extent of dumping, if any, by the
investigated companies, contrary to the first sentence of Article 2.4.2 of the Anti-Dumping Agreement.
B. T
HE UNITED STATES
3.3 The United States acknowledges the accuracy of Thailand's description of the USDOC's use
of "zeroing" in calculating the dumping margins fo r the individually investigated exporters whose
margins of dumping were not based on total facts available. The United States recognizes that, in
US – Softwood Lumber V , the Appellate Body found that the us e of "zeroing" with respect to the
average-to-average comparison methodology in investig ations was inconsistent with Article 2.4.2, by
interpreting the terms "margins of dumping" and "a ll comparable export transactions" as used in the

first sentence of Article 2.4.2, in an integrated manner. 5 The United States also acknowledges that
this reasoning is equally applicable with respect to Thailand's claim in the present case.
IV. ARGUMENTS OF THE PARTIES
4.1 The arguments of the parties are set out in thei r written submissions to the Panel. Thailand
made further arguments in its response to a question from the Panel. The parties' written submissions,
and Thailand's response to the Panel' s question are attached to this report as annexes (see List of
Annexes, page ii).
V. ARGUMENTS OF THE THIRD PARTIES
5.1 Argentina, the European Comm unities, Japan, Korea and Chinese Taipei have reserved their
rights to participate in the Panel proceedings as th ird parties. The arguments of Argentina, the
European Communities and Japan are set out in th eir written submissions. Korea and Chinese Taipei
did not provide written submissions. The third parties' written submissions or their executive
summaries thereof are attached to this report as annexes (see List of Annexes, page ii).
VI. INTERIM REVIEW
6.1 The Panel issued its Interim Report to the parties on 11 December 2009. On
18 December 2009, both parties submitted written re quests for the review of precise aspects of the
Interim Report. Neither party exercised its righ t to submit written comments on the other party's
written request, or to request an interim review meeting. In accordance with Article 15.3 of the DSU,
this section of the Panel's Report sets out the arguments made at the interim review stage.
A. THAILAND
6.2 Thailand requested the Panel to delete a refe rence to a prior WTO dispute settlement case
from para. 6.2 of the Interim Report, on the ground that such case did not address the precise matter at
issue in this case. We have deleted the relevant reference from para. 7.2 of our Report.
6.3 Thailand requested that we insert the words "som e of" into footnote 13 of the Interim Report,
to clarify that Thailand also relied on evidence othe r than the USDOC's preliminary determination, in
particular the USDOC computer programme. We have amended footnote 14 of the Report
accordingly. We have also included a new para. 7. 16 in the Report, addressing the relevant parts of
the USDOC computer programme.
6.4 Thailand requested that we modify para. 6.17 of the Interim Report to ensure consistency with
the scope of our conclusion in para. 7.1 of the In terim Report, and with the arguments set forth in
Thailand's written submission. We have amended para. 7.18 of our Report accordingly.
B. THE UNITED STATES
6.5 The United States requested the inclusion of a re ference to consultations in para. 1.1 of the
Interim Report. We have amended para. 1.1 of the Report accordingly.
6.6 The United States requested a clarification in para. 6.9 of the Interim Report. We have
introduced the clarification sought by the United States into para. 7.9 of the Report.

5 Appellate Body Report, US – Softwood Lumber V, paras. 62-117.

6.7 Regarding paras. 6.13 and 6.15, and footnote 13, of the Interim Report, the United States
requested the inclusion of a reference to Tha iland's reliance on evidence regarding the USDOC's
computer programme. We have amended para. 7.13 and footnote 14 of the Report, and included a
new para. 7.16 in the Report regarding the relevant parts of the USDOC computer programme.
6.8 The United States requested a change in para. 6.16 of the Interim Report, to ensure
consistency with Thailand's written submission an d para. 3.1 of the Interim Report. We have
amended para. 7.17 of the Report accordingly.
6.9 The United States requested that we modify pa ra. 6.17 of the Interim Report to ensure
consistency with the scope of our conclusion in para. 7.1 of the In terim Report. We have amended
6.10 The United States requested linguistic changes to para. 6.23 of the Interim Report. We have
modified para. 7.24 of our Report accordingly.
VII. FINDINGS
7.1 Thailand claims that the United States acted inc onsistently with Article 2.4.2, first sentence,
of the Anti-Dumping Agreement by using "zeroing" in the Final Determination, as amended, and the
Order to determine the dumping margins for individu ally investigated Thai exporters whose margins
of dumping were not based on total facts availabl e. The United States does not contest Thailand's
claim.
7.2 The issues raised in this case are very simila r to those addressed first by the panel in US –
Shrimp (Ecuador), and subsequently by the panel in US – Shrimp (Thailand) . Like the latter panel,
we agree with the approach adopted by the US – Shrimp (Ecuador) panel, and are guided by it.
7.3 We begin by considering, in light of the fact that the United States does not contest Thailand's
claim, our role under Article 11 of the DSU, and the burden of proof to be discharged by Thailand.
We then consider whether Thailand has established th at the USDOC "zeroed" in the measure at issue,
and whether Thailand has established that the meth odology used by the USDOC is the same in all
legally relevant respects as the methodol ogy reviewed by the Appellate Body in US – Softwood
Lumber V. Thereafter, we consider whether Thailand has established that the methodology applied by
the USDOC is inconsistent with Article 2.4.2 of the Anti-Dumping Agreement.
(a) The role of the Panel under Article 11 of the DSU
7.4 Article 11 of the DSU provides:
"The function of panels is to assist th e DSB in discharging its responsibilities under
this Understanding and the cove red agreements. Accordingly, a panel should make
an objective assessment of the matter before it, including an objective assessment of
the facts of the case and the applicability of and conformity with the relevant covered
agreements, and make such other findings as will assist the DSB in making the
recommendations or in giving the rulings pr ovided for in the covered agreements.
Panels should consult regularly with the parties to the dispute and give them adequate
opportunity to develop a mutually satisfactory solution."6 (emphasis added)

6 We note that Article 17.6 of the Anti-Dumping Agreement – setting forth the special standard of
review applicable to disputes under the Anti-Dumping Agreement – also applies to this dispute. Given that the

7.5 Notwithstanding the United States' decision not to contest Thailand's claim, we consider that
we are still bound by Article 11 of the DSU to make an "objective assessment of the facts of the case
and the applicability of and conformity with the re levant covered agreements , and make such other
findings as will assist the DSB in making the recommendations or in giving the rulings provided for in
the covered agreements".
(b) Burden of proof
7.6 The panel in US – Shrimp (Ecuador) made the following findings in respect of burden of
proof:
"Because of its singularity, this dispute raises in a particularly acute fashion the issue
of the burden of proof.
The burden of proof lies, in WTO dispute se ttlement proceedings, with the party that
asserts the affirmative of a particular claim or defence. Ecuador, as the complaining
party, must therefore make a prima facie cas e of violation of the relevant provisions
of the relevant WTO agreements. The bur den would then shift to the responding
party (here the United States), to adduce evidence to rebut the presumption that
Ecuador's assertions are true. In this context, we recall that 'a prima facie case is one
which, in the absence of effective refutati on by the defending party, requires a panel,
as a matter of law, to rule in favour of the complaining party presenting the prima
facie case'.
In our view, the issue of the burden of proof is of particular importance in this case.
This is because Ecuador has made factual and legal claims before the Panel which the
United States does not contest. Yet, the f act that the United States does not contest
Ecuador's claims is not a sufficient basis fo r us to summarily conclude that Ecuador's
claims are well-founded. Rather, we can onl y rule in favour of Ecuador if we are
satisfied that Ecuador has made a prima facie case. We take note in this regard that
the Appellate Body has cautioned panels against ruling on a claim before the party
bearing the burden of proof has made a prima facie case. In EC – Hormones , the
Appellate Body ruled that the Panel erred in law when it absolv ed the complaining
parties from the necessity of establishing a prima facie case and shifted the burden of
proof to the responding party:
'In accordance with our ruling in United States – Shirts and Blouses ,
the Panel should have begun the analysis of each legal provision by
examining whether the United States and Canada had presented
evidence and legal arguments sufficient to demonstrate that the EC
measures were inconsistent with the obligations assumed by the
European Communities under each Article of the SPS Agreement
addressed by the Panel .... Only after such a prima facie
determination had been made by the Panel may the onus be shifted to
the European Communities to bring forward evidence and arguments
to disprove the complaining party's claim.'

More recently, in US – Gambling, the Appellate Body indicated that "[a] panel errs
when it rules on a claim for which the co mplaining party has failed to make a prima
facie case", and noted that:

United States does not contest Thailand's claim, it is not necessary for us to consider the application of this
provision in detail.

'A prima facie case must be based on "evidence and legal argument"
put forward by the complaining party in relation to each of the
elements of the claim. A complaining party may not simply submit
evidence and expect the panel to divine from it a claim of WTO-
inconsistency. Nor may a complaining party simply allege facts
without relating them to its legal arguments.
In the context of the sufficiency of panel requests under Article 6.2 of
the DSU, the Appellate Body has found that a panel request:
... must plainly connect the challenged measure(s)
with the provision(s) of the covered agreements
claimed to have been infringed, so that the
respondent party is aware of the basis for the alleged
nullification or impairment of the complaining
party's benefits.
Given that such a requirement applies to panel requests at the outset
of a panel proceeding, we are of the view that a prima facie case—
made in the course of submissions to the panel—demands no less of
the complaining party. The evidence and arguments underlying a
prima facie case, therefore, must be sufficient to identify the
challenged measure and its basic im port, identify the relevant WTO
provision and obligation contained therein, and explain the basis for
the claimed inconsistency of the measure with that provision.'
Thus, notwithstanding the fact that the United States is not seeking to refute
Ecuador's claims, we must satisfy ourselves that Ecuador has established a prima
facie case of violation, and notably that it has presented 'evidence and argument...
sufficient to identify the challenged measure and its basic import, identify the relevant
WTO provision and obligation contained th erein, and explain the basis for the
claimed inconsistency of the measure with that provision.'"
7 (footnotes omitted)
7.7 We agree with this reasoning of the panel in US – Shrimp (Ecuador), and adopt it as our own.
Accordingly, notwithstanding the fact that the Unite d States is not seeking to refute Thailand's claim,
we must satisfy ourselves that Thailand has established a prima facie case of violation of Article 2.4.2
of the Anti-Dumping Agreement.
(c) Has Thailand established that the USDOC "zeroed" in the measure at issue?
7.8 We now consider whether Thailand has establishe d that the USDOC "zeroed" in the measure
at issue.
7.9 In support of its factual assertion that the USDO C "zeroed" in the measure at issue, Thailand
refers to a copy of the computer programme used by the USDOC to calculate dumping margins in the
Final Determination, as amended, th at was provided to some of the i nvestigated exporters. We have
studied the relevant computer programme, and find that it indicates the use of "zeroing" in the
calculation of the dumping margins for the relevant Thai exporters. In particular, lines 2567-2570
provide that "IF EMARGIN LE 0 THEN EMARGIN = 0", i.e., that margins on individual models less
than zero should be set to zero. In addition, lines 2633-2637 and 2693-2696 pr ovide that the overall

7 Panel Report, US – Shrimp (Ecuador), paras. 7.7 – 7.11.

margin of dumping shall only be calculated on th e basis of comparisons "WHERE EMARGIN GT 0",
i.e., where the margin for a particular model was greater than zero.8
7.10 Furthermore, we recall that "the United St ates acknowledges the accuracy of Thailand's
description of the [USDOC]'s use of 'zeroing' in calculating the dumping margins for the individually
investigated exporters whose margins of dumpi ng were not based on total facts available". 9 In these
circumstances, we are satisfied that Thailand h as demonstrated that the USDOC "zeroed" in the
measure at issue.
(d) Has Thailand established that the methodology used by the USDOC is the same in all legally
relevant respects as the methodology reviewed by the Appellate Body in US – Softwood
Lumber V?
7.11 We now determine whether the "zeroing" methodology used by the USDOC to calculate the
dumping margins at issue here was, as alleged by Th ailand, the same in all legally relevant respects as
the one the Appellate Body, in US – Softwood Lumber V , found to be inconsiste nt with Article 2.4.2
of the Anti-Dumping Agreement.
7.12 The Appellate Body in US – Softwood Lumber V , described "zeroing" as applied by the
USDOC in that investigation as follows:
First, USDOC divided the product under i nvestigation (that is, softwood lumber from
Canada) into sub-groups of identical, or br oadly similar, product types. Within each
sub-group, USDOC made certain adjustment s to ensure price comparability of the
transactions and, thereafter, calculated a weighted average normal value and a
weighted average export price per unit of the product type. When the weighted
average normal value per unit exceeded the weighted average export price per unit for
a sub-group, the difference was regarded as the "dumping margin" for that
comparison. When the weighted average normal value per unit was equal to or less
than the weighted average export price per unit for a sub-group, USDOC took the
view that there was no "dumping margin" for that comparison. USDOC aggregated
the results of those sub-group comparisons in which the weighted average normal
value exceeded the weighted average export price—those where the USDOC
considered there was a "dumping margin"—after multiplying the difference per unit
by the volume of export transactions in that sub-group. The results for the sub-groups
in which the weighted average normal value was equal to or less than the weighted
average export price were treated as zero for purposes of this aggregation, because
there was, according to USDOC, no "dumping margin" for those sub-groups. Finally,
USDOC divided the result of this aggregati on by the value of all export transactions
of the product under investigation ( including the value of export transactions in the
sub-groups that were not included in the aggregation). In this way, USDOC obtained
an "overall margin of dumping", for each exporter or producer, for the product under
investigation (that is, softwood lumber from Canada).
10
7.13 In support of its claim that the methodology used by the USDOC is the same in all legally
relevant respects as the methodology reviewed by the Appellate Body in US – Softwood Lumber V ,
Thailand relies on the description of the methodology set forth in the USDOC's notice of preliminary
determination of sales at less than fair value in th e investigation at issue, as well as the computer

8 Exhibit THA-4.
10 Appellate Body Report, US – Softwood Lumber V, para. 64 (emphasis original; footnote omitted).

programme used to determine the dumping margins. In its notice of preliminary determination, the
USDOC stated that:

"To determine whether sales of PRCBs to the United States by Thai Plastic Bags and
Universal in this investigation were made at less than fair value, we compare EP
[export price] or constructed export price (C EP) to normal value, as described in the
'US Price' and 'Normal Value' sections of this notice. In accordance with
section 777A(d)(1)(A)(i) of the Act, we calculated weighted-average EPs and CEPs.
In making the product comparisons, we ma tched foreign like products based on the
physical characteristics reported by the respondents in the following order of
importance ..."
11
7.14 The USDOC further explained that:
We compared U.S. sales with sales of th e foreign like product in the home market on
the basis of the physical characteristic s described under Fair Value Comparisons
above. Wherever we were unable to matc h a U.S. model to identical merchandise
sold in the home market, we selected the most similar model of subject merchandise
in the home market as the foreign like product.12
7.15 Thereafter, the USDOC explained that the wei ghted-average dumping margin was "equal to
the weighted-average amount by which the normal value exceeds the EP or CEP".13
7.16 In addition, the abovementioned USDOC co mputer programme shows that the USDOC
determined weighted-average U.S. prices by m odel (lines 1976-2005); determined weighted-average
normal values by model (lines 985-1037); matched home market and U.S. sales by model (lines 2007-
2179); and made model-by-model calculations (lines 2417-2555), including the subtraction of U.S.
price from normal value (lines 2541-2543).
7.17 In our view, this evidence is sufficient to est ablish that the USDOC (i) identified different
"models," i.e., types, of products based on the most releva nt product characteristics, (ii) calculated
weighted average prices in the United States and we ighted average normal values in the comparison
market on a model-specific basis, for the entire peri od of investigation, (iii) compared the weighted
average normal value of each model to the weighted average United States price for that same model,
and (iv) calculated the dumping margin for an exporter by summing up the amount of dumping for
each model and then dividing it by the aggregated U.S. price for all models. 14 We recall that we have
already found that Thailand has established that (v ) the USDOC set to zero all negative margins on
individual models before summing the total amount of dumping for all models.
7.18 In light of these considerations, and in the ab sence of any denial by the United States, we are
satisfied that Thailand has demonstrated that th e methodology applied by the USDOC in calculating
the margins of dumping that were not based on to tal facts available in the Order imposing anti-
dumping duties on certain polyethylene retail carrier bags from Thailand, and the Final Determination
(as amended) leading to that Order, was the same in all legally relevant respects as the methodology

11 Notice of Preliminary Determination of Sales at Less than Fair Value and Postponement of Final
Determination: Polyethylene Retail Carrier Bags from Thailand , 69 Fed. Reg. 3552, 3554 (26 January 2004),
Exhibit THA-9.
12 Ibid., at 3555.
13 Ibid., at 3557.
14 Although some of this evidence pertains to the USDOC's preliminary determination, the United
States has not argued that the USDOC amended its methodology when making the Final Determination, or any
amendment thereto.

that was found by the Appellate Body in US – Softwood Lumber V to be inconsistent with Article 2.4.2
of the Anti-Dumping Agreement.
(e) Has Thailand established that the methodology ap plied by the USDOC is inconsistent with
Article 2.4.2 of the Anti-Dumping Agreement?
7.19 We now turn to the legal analysis of Thailand' s claim, i.e., whether the measure it challenges
is inconsistent with Article 2.4.2 of the Anti-Dumping Agreement. Article 2.4.2 provides as follows:
"Article 2
Determination of Dumping

2.4.2 Subject to the provisions governing fair comparison in paragraph 4, the
existence of margins of dumping during the investigation phase shall normally be
established on the basis of a comparison of a weighted average normal value with a
weighted average of prices of all comparable export transactions or by a comparison
of normal value and export prices on a transaction-to-transaction basis. A normal
value established on a weighted average basis may be compared to prices of
individual export transactions if the author ities find a pattern of export prices which
differ significantly among different purchasers, regions or time periods, and if an
explanation is provided as to why such differences cannot be taken into account
appropriately by the use of a weighted av erage-to-weighted average or transaction-to-
transaction comparison."
7.20 Thailand relies on the Appellate Body Report in US – Softwood Lumber V in support of its
claim of inconsistency with Article 2. 4.2. In particular, Thailand relies
15 on the Appellate Body's
finding that the terms "margins of dumping" and "a ll comparable export transactions" in Article 2.4.2
must be interpreted in an "integrated manner" 16, such that where "an investigating authority has
chosen to undertake multiple comparisons, the inv estigating authority necessarily has to take into
account the results of all those comparisons in or der to establish margins of dumping for the product
as a whole under Article 2.4.2".17
7.21 While we are not bound by the reasoning in pr ior Appellate Body and/or panel reports,
adopted Reports create legitimate expectations among WTO Members18, and "following the Appellate
Body's conclusions in earlier disputes is not only appropriate, but is what would be expected from
panels, especially where the issues are the same".19
7.22 The panel in US – Shrimp (Ecuador) explained its understanding of the Appellate Body's
reasoning in US – Softwood Lumber V as follows:
"The Appellate Body began its analysis with the text of Article 2.4.2 and noted that
the question before it was the proper interpretation of the terms 'all comparable export
transactions' and 'margins of dumping' in Ar ticle 2.4.2. In examining the arguments
of the parties with respect to these phrases, the Appellate Body concluded that the

16 Appellate Body Report, US – Softwood Lumber V, paras. 86-103.
17 Ibid., para. 98.
18 Appellate Body Report , Japan Alcoholic Beverages II , p. 14; Appellate Body Report, US – Shrimp
(Article 21.5 – Malaysia), paras. 108-109; Appellate Body Report, US – Softwood Lumber V, paras. 109-112.
19 Appellate Body Report, US – Oil Country Tubular Goods Sunset Reviews, para. 188.

parties' disagreement centered on whether a Member could take into account 'all'
comparable export transactions only at the sub-group level, or whether such
transactions also had to be taken into account when the results of the sub-group
comparisons are aggregated. To examine that issue, the Appellate Body noted the
definition of dumping in Article 2.1 of the Anti-Dumping Agreement. The Appellate
Body found that 'it [was] clear from the texts of [Article VI:1 of the GATT 1994 and
Article 2.1 of the Anti-Dumping Agreement] that dumping is defined in relation to a
product as a whole as defined by the investig ating authority'. The Appellate Body
further considered that the definition of 'd umping' contained in Article 2.1 applies to
the entire Agreement, including Article 2.4.2, and that "'[d]umping', within the
meaning of the Anti-Dumping Agreement, can therefore be found to exist only for the
product under investigation as a whole, and cannot be found to exist only for a type,
model, or category of that product." Next, the Appellate Body relied on its Report in
EC – Bed Linen , in which it stated that '[w]hatever the method used to calculate the
margins of dumping ... these margins must be, and can only be, established for the
 product under investigation as a whole'. Thus, the Appellate Body noted that "[a]s
with dumping, 'margins of dumping' can be found only for the product under
investigation as a whole, and cannot be found to exist for a product type, model, or
category of that product". The Appellate Body therefore rejected the United States'
arguments in that case that Article 2.4.2 does not apply to the aggregation of the
results of multiple comparisons at the sub- group level; for the Appellate Body, while
an investigating authority may undertake mu ltiple averaging to establish margins of
dumping for a product under investigation, the results of the multiple comparisons at
the sub-group levels are not margins of dumpi ng within the meaning of Article 2.4.2;
they merely reflect intermediate calculations made by an investigating authority in the
context of establishing margins of dumping for the product under investigation. It is
only on the basis of aggregating all
 such intermediate values that an investigating
authority can establish margins of dumping for the product under investigation as a
whole. On this basis, the Appellate Body held that zeroing, as applied by the
USDOC in US – Softwood Lumber V:
mean[t], in effect, that at least in the case of some export transactions,
the export prices are treated as if they were less than what they
actually are. Zeroing, therefore, does not take into account the
entirety of the prices of some export transactions, namely, the prices
of export transactions in those sub-groups in which the weighted
average normal value is less than the weighted average export price.
Zeroing thus inflates the margin of dumping for the product as a
whole.
The Appellate Body on this basis conclude d that the treatment of comparisons for
which the weighted average normal value is less than the weighted average export
price as "non-dumped" comparisons was not in accordance with the requirements of
Article 2.4.2 of the Anti-Dumping Agreement. As a result, the Appellate Body upheld
the Panel's finding that the United States had acted inconsistently with Article 2.4.2 of
the Anti-Dumping Agreement in determining the existence of margins of dumping on
the basis of a methodology incorporating the practice of zeroing."
20
7.23 The panel in US – Shrimp (Ecuador) further found that "there is now a consistent line of
Appellate Body Reports, from EC – Bed Linen to US – Zeroing (EC) that holds that 'zeroing' in the

20 Panel Report, US – Shrimp (Ecuador), paras. 7.38 and 7.39 (footnotes omitted).

context of the weighted average-to-weighted aver age methodology in original investigations (first
methodology in the first sentence of Article 2.4.2) is inconsistent with Article 2.4.2".21
7.24 We have carefully considered th e Appellate Body's reasoning in US – Softwood Lumber V
and taken into consideration the finding of the panel in US – Shrimp (Ecuador) that there is a
consistent line of Appellate Body Reports finding that "zeroing" in the context of the weighted
average-to-weighted average methodology in original i nvestigations is inconsistent with Article 2.4.2,
first sentence. Given that the issu es raised by Thailand's claim are id entical in all material respects to
those addressed by the Appellate Body in Softwood Lumber V , we are satisfied that Thailand has
established a prima facie case that the use of zeroi ng by the USDOC in the calculation of the margins
of dumping in respect of the measures at issue is inconsistent with the United States' obligations under
Article 2.4.2 of the Anti-Dumping Agreement because the USDOC did not calculate these dumping
margins on the basis of the "product as a whole", taking into account all comparable export
transactions in calculating the margins of dumpi ng. We note also that the United States
"acknowledges" that the reasoning of the Appellate Body in US – Softwood Lumber V "is equally
applicable with respect to Thaila nd's claim regarding the individua lly investigated exporters whose
margins of dumping were not based on total facts available in the investigation at issue".
22
7.25 In light of our finding that Thailand has made a prima facie case of violation in respect of the
measure at issue, and in the absence of arguments from the United States to the contrary, we rule in
favour of Thailand. We therefore conclude th at the USDOC, by using "zeroing" in the manner
described above, has acted inconsistently with the Un ited States' obligations under Article 2.4.2 of the
Anti-Dumping Agreement.
VIII. CONCLUSIONS AND RECOMMENDATION
8.1 In light of the above findings, we conclude that the United States acted inconsistently with
Article 2.4.2, first sentence, of the Anti-Dumping Agreement by using "zeroing" in the Final
Determination, as amended, and the Order to determine the dumping margins for individually
investigated Thai exporters whose margins of dumping were not based on total facts available.
8.2 Under Article 3.8 of the DSU, in cases where there is an infringement of the obligations
assumed under a covered agreement, the action is considered prima facie to constitute a case of
nullification or impairment of benefits under that ag reement. Accordingly, we conclude that, to the
extent the United States has acted incons istently with the provisions of the Anti-Dumping Agreement,
it has nullified or impaired benefits accruing to Thailand under that Agreement. We therefore
recommend that the Dispute Settlement Body request the United States to bring its measures into
conformity with its obligations under the Anti-Dumping Agreement.