  United States Court of Appeals
      for the Federal Circuit
                ______________________

              GLYCINE & MORE, INC.,
                 Plaintiff-Appellee

                          v.

                  UNITED STATES,
                     Defendant

       GEO SPECIALTY CHEMICALS, INC.,
              Defendant-Appellant
             ______________________

                      2017-1312
                ______________________

   Appeal from the United States Court of International
Trade in No. 1:13-cv-00167-TCS, Chief Judge Timothy C.
Stanceu.
                ______________________

              Decided: January 23, 2018
               ______________________

    RONALD MARK WISLA, Kutak Rock LLP, Washington,
DC, argued for plaintiff-appellee. Also represented by
LIZBETH ROBIN LEVINSON.

    DAVID M. SCHWARTZ, Thompson Hine LLP, Washing-
ton, DC, argued for defendant-appellant.
                 ______________________

     Before MOORE, PLAGER, and CHEN, Circuit Judges.
2                    GLYCINE & MORE, INC.   v. UNITED STATES



PLAGER, Circuit Judge.
    This case turns on an important principle in adminis-
trative law, involving a basic tenet of the Administrative
Procedure Act (hereafter “APA”), to which the defendant
agency, the Department of Commerce, is subject. See
generally 5 U.S.C. §§ 551 et seq. The question presented
is—can an agency regulation, previously adopted by
formal notice-and-comment rulemaking procedure pursu-
ant to the APA, be amended by a guidance document that
is not so enacted? The case comes to us on appeal from a
decision of the United States Court of International Trade
(“CIT”).
     Defendant-appellant GEO Specialty Chemicals, Inc.
(“GEO”) appeals the CIT’s judgment. That judgment
affirmed a decision by the United States Department of
Commerce (“Commerce”). 1       Commerce’s decision, on
remand from an earlier CIT order, extended the deadline
for plaintiff-appellee Glycine & More, Inc. (“Glycine &
More”) to withdraw a request for an administrative re-
view of an antidumping order, accepted the withdrawal,
and rescinded the review.
    Commerce made its decision under protest. The CIT
in a prior order had invalidated Commerce’s change of
methodology for evaluating such time-extending petitions,
announced in a “Notice,” and ordered Commerce to re-
evaluate its original denial of the withdrawal request
pursuant to the court’s understanding of the governing
regulation, 19 C.F.R. § 351.213(d)(1).
   Identifying more fully the parties to this litigation
may be helpful since their roles evolve as the case devel-


    1   When the context requires, the term “Commerce”
refers as well to the Secretary of that department or the
Secretary’s designee.
GLYCINE & MORE, INC.   v. UNITED STATES                   3



ops. The proceedings before Commerce at issue were
requested by two parties. One of those two parties was
Baoding Mantong Fine Chemistry Co., Ltd. (“Baoding
Mantong”), a Chinese producer and exporter of glycine.
The other party was GEO Specialty Chemicals, Inc.
(“GEO”), the defendant-appellant, a U.S. producer of
glycine. A third party, plaintiff-appellee Glycine & More,
filed a notice of appearance in the proceedings and partic-
ipated in the review. Glycine & More is a U.S. importer of
glycine manufactured by Baoding Mantong and an affili-
ate of Baoding Mantong.
    Though the United States is listed as a party defend-
ant, and despite the fact that what is at issue is the
Commerce Department’s understanding of its own regula-
tions, neither Commerce nor the United States govern-
ment have participated in the appeal.
    On appeal, GEO argues that the first CIT decision in
the case forced Commerce to adopt an erroneous interpre-
tation of its regulation and thus forced Commerce in its
later decision to reach an erroneous result. Glycine &
More argues to uphold the decisions of the CIT. For the
reasons we shall explain, we agree with the CIT’s action
and affirm its judgment.
                        BACKGROUND
       Administrative Reviews Initiated by Request
    Under the law, Commerce may determine whether
foreign merchandise is being sold or is likely to be sold in
the United States at less than its fair value. See 19
U.S.C. §§ 1673, 1677. The International Trade Commis-
sion (“ITC”) separately determines whether an industry in
the United States is materially injured or threatened with
material injury by the import, sales, or likelihood of sales
of that foreign merchandise. Id. When the ITC has so
determined, Commerce then issues what is called an
4                      GLYCINE & MORE, INC.   v. UNITED STATES



antidumping order, and imposes a special duty on the
import of such products. See id.
    If Commerce thereafter receives a request for an ad-
ministrative review of a previously issued antidumping
duty order, Commerce must conduct such a review at
least once during each 12-month period beginning on the
anniversary date of the publication of the antidumping
duty order. See 19 U.S.C. § 1675(a)(1). Although Con-
gress in the governing legislation required that Commerce
engage in such a review if properly requested, Congress
did not provide for the situation at hand—how Commerce
should proceed if a request, once made, is withdrawn.
    To address this scenario, the Commerce Department
proposed and adopted a regulation. In the adopted regu-
lation, Commerce set forth rules for evaluating timely and
untimely withdrawals:
    (d) Rescission of administrative review—(1) With-
    drawal of request for review. The Secretary will
    rescind an administrative review under this sec-
    tion, in whole or in part, if a party that requested
    a review withdraws the request within 90 days of
    the date of publication of notice of initiation of the
    requested review. The Secretary may extend this
    time limit if the Secretary decides that it is rea-
    sonable to do so.
19 C.F.R. § 351.213(d)(1); see also id. § 351.102(b)(44)
(defining “Secretary” as “the Secretary of Commerce or a
designee”).
    In 2012 Baoding Mantong and GEO each requested
review of an antidumping order that Commerce had
imposed on imports of glycine from the People’s Republic
of China. Later, just at the end of the 90-day period after
Commerce had published notice that it was initiating a
review, GEO filed a notice of withdrawal of its petition for
review. Shortly thereafter, Baoding Mantong filed its
GLYCINE & MORE, INC.   v. UNITED STATES                  5



notice of withdrawal of its request for review, accompa-
nied by a request for extension of time to file its with-
drawal; the notice of withdrawal was filed after the 90-
day period provided in the regulation had expired.
    Under the final sentence in the regulation, “[t]he Sec-
retary may extend this time limit if the Secretary decides
that it is reasonable to do so.” 19 C.F.R. § 351.213(d)(1).
In response to the Baoding Mantong notice and request,
the Secretary declined to extend the 90-day time limit for
a withdrawal, thus causing the notice of withdrawal to be
ineffective.
    That final sentence had remained unchanged since
the publication of predecessor rules years earlier, and
upon which the current rule, § 351.213(d)(1), was based.
Further, as we shall explain, Commerce’s understanding
and application of that regulatory sentence remained
essentially consistent over the years—until 2011.
   In 2011, Commerce announced in a published guid-
ance document a view of that sentence that dramatically
changed its meaning. 2 The question raised in this appeal



   2    “Guidance” or “guidance document” is a frequent-
ly-used term to describe an agency’s instructions pub-
lished informally, that is without formal notice and
comment rulemaking pursuant to 5 U.S.C. § 553(b)(A) of
the APA. It encompasses what are termed general state-
ments of policy and interpretive rules. The extent to
which such guidance is or should be binding, and on
which agency constituencies, is a matter of some difficul-
ty—see, e.g., Administrative Conference of the United
States (“ACUS”), Recommendation 2017-5, Agency Guid-
ance Through Policy Statements, 82 Fed. Reg. 61,728,
61,734 (Dec. 29, 2017), addressed specifically to general
policy statements; see the discussion at n.3, below, re-
6                      GLYCINE & MORE, INC.   v. UNITED STATES



is whether the Secretary’s refusal, pursuant to the 2011
guidance document, to extend the time limit was legally
proper. Was it made consistent with the requirements set
forth in the governing regulation, specifically with the
criterion in the final sentence of that regulation?
            History of 19 C.F.R. § 351.213(d)(1)
    The current regulation was published as a Final Rule
in 1997. However, as proposed in 1996, the regulation did
not allow for untimely withdrawals. Instead, the pro-
posed regulation only allowed for timely withdrawals—
and even that was discretionary:
    (d) Rescission of administrative review. (1) With-
    drawal of request for review. The Secretary may
    rescind an administrative review under this sec-
    tion, in whole or in part, if a party that requested
    a review withdraws the request not later than 90
    days after the date of publication of notice of initi-
    ation of the requested review.
Antidumping Duties; Countervailing Duties, 61 Fed. Reg.
7308, 7365 (emphasis added) (proposed Feb. 27, 1996).
    The omission of any language allowing for untimely
withdrawals in the proposed regulation was a puzzle. 19
C.F.R. Part 351 was, in part, a consolidation of existing
regulations. See id. at 7308 (discussing consolidation in
context of proposed rule). See also Antidumping Duties;
Countervailing Duties, 62 Fed. Reg. 27,296, 27,296 (May
19, 1997) (discussing consolidation in context of final



garding interpretive rules. See also Nicholas R. Parrillo,
Federal Agency Guidance: An Institutional Perspective
(2017), a thorough and exhaustive study based on empiri-
cal data as well as legal analyses, commissioned by
ACUS.
GLYCINE & MORE, INC.   v. UNITED STATES                   7



rule). Both of those then-existing regulations included
identical language allowing for untimely withdrawals:
“The Secretary may extend this [90-day] time limit if the
Secretary decides that it is reasonable to do so.” 19 C.F.R.
§§ 353.22(a)(5), 355.22(a)(3) (1995).
    The omission of this language in the newly proposed
rule was even more puzzling in light of Commerce’s
statement, when proposing § 351.213, that “certain
changes are worth noting,” but no mention was made of
this particular change. See Antidumping Duties; Coun-
tervailing Duties, 61 Fed. Reg. at 7317. Instead, Com-
merce merely stated that “Paragraph (d) deals with the
rescission (previously referred to as ‘termination’) of
administrative reviews, and clarifies that the Department
may rescind a review that the Secretary self-initiated or
in which there are no entries, exports, or sales to be
reviewed.” Id.
    In adopting its Final Rule, however, Commerce re-
turned the missing sentence. It explained that it added
the language allowing untimely withdrawals in response
to comments and in light of former §§ 353.22 and 355.22:
   Commenting on proposed § 351.213(d)(1) and its
   90-day limit on withdrawals of a request for a re-
   view, one commenter suggested that the provision
   be modified so as to allow the Department to re-
   scind an administrative review after the 90-day
   period has expired if (1) the party that initially
   requested the review withdraws its request, and
   (2) no other party objects to the rescission within
   a reasonable period of time. According to the
   commenter, such a rule would avoid the burden
   and expense of completing reviews that none of
   the parties want.
   We agree that the 90-day limitation may be too
   rigid. However, we believe that the Department
   must have the final say concerning rescissions of
8                     GLYCINE & MORE, INC.   v. UNITED STATES



    reviews requested after 90 days in order to pre-
    vent abuse of the procedures for requesting and
    withdrawing a review. For example, we are con-
    cerned with the situation in which a party re-
    quests a review, the Department devotes
    considerable time and resources to the review,
    and then the party withdraws its requests once it
    ascertains that the results of the review are not
    likely to be in its favor. To discourage this behav-
    ior, the Department must have the ability to deny
    withdrawals of requests for review, even in situa-
    tions where no party objects.
    Therefore, in § 351.213(d)(1), we have retained the
    90-day requirement. In addition we have added a
    new     sentence,     taken     from    19    C.F.R.
    §§ 353.22(a)(5) and 355.22(a)(3), that essentially
    provides that if a request for rescission is made af-
    ter the expiration of the 90-day deadline, the deci-
    sion to rescind a review will be at the Secretary’s
    discretion.
62 Fed. Reg. at 27,317.
    A similar explanation for giving the Secretary the dis-
cretion to extend the 90-day deadline in appropriate cases
was given when the sentence was added to the earlier
antidumping regulation, again during the notice-and-
comment process:
    Department’s Position [in response to comments]:
    . . . We recognize the importance to the party
    submitting the request for review of knowing the
    final results of the immediately preceding review,
    if any. Therefore, we are modifying paragraph (a)
    to permit the party that submits a request to
    withdraw the request under certain conditions. If
    a relevant review has not been completed before
    the end of the anniversary month during which
    the new request is submitted, the party that sub-
GLYCINE & MORE, INC.   v. UNITED STATES                     9



   mitted the new request may withdraw it not later
   than 90 days after the date of publication of notice
   of initiation of the requested review. The Secre-
   tary may extend the time limit if it is reasonable
   to do so.
Antidumping Duties, 54 Fed. Reg. 12,742, 12,755 (Mar.
28, 1989). See also a similar explanation in the context of
allowing untimely withdrawals in former 19 C.F.R.
§ 355.22(a)(3), Countervailing Duties, 53 Fed. Reg.
52,306, 52,328 (Dec. 27, 1988).
                 Commerce’s 2011 Notice
    The history of § 351.213(d)(1) thus establishes Com-
merce’s understanding of the circumstances under which
it would be reasonable to extend a deadline for filing a
withdrawal. The criteria for what would be a reasonable
ground for extension reflects concerns for not wasting
departmental resources, for giving parties an opportunity
to know the results of prior administrative reviews when
applicable, and for not conducting undesired reviews,
among other considerations.
    Despite this record, in August 2011 Commerce pub-
lished what it denominated as a “Notice” in which it
dramatically changed its approach to the extension provi-
sion in § 351.213(d)(1):
   Pursuant to section 351.213(d)(1) of the Depart-
   ment’s regulations, a party that has requested a
   review may withdraw that request within 90 days
   of the date of publication of the notice of initiation
   of the requested review. The regulation provides
   that the Department may extend this time if it is
   reasonable to do so. In order to provide parties
   additional certainty with respect to when the De-
   partment will exercise its discretion to extend this
   90-day deadline, interested parties are advised
   that, with regard to reviews requested on the ba-
10                    GLYCINE & MORE, INC.   v. UNITED STATES



     sis of anniversary months on or after August
     2011, the Department will not consider extending
     the 90-day deadline unless the requestor demon-
     strates that an extraordinary circumstance has
     prevented it from submitting a timely withdrawal
     request. Determinations by the Department to
     extend the 90-day deadline will be made on a
     case-by-case basis.
     The Department is providing this notice on its
     Web site, as well as in its “Opportunity to Request
     Administrative Review” notices, so that interested
     parties will be aware of the manner in which the
     Department intends to exercise its discretion in
     the future.
See Antidumping or Countervailing Duty Order, Finding,
or Suspended Investigation; Opportunity to Request
Administrative Review, 76 Fed. Reg. 45,773, 45,773 (Aug.
1, 2011) (the “2011 Notice”).
    Commerce did not make clear whether this “Notice”
was intended as a statement of general policy or as an
interpretive rule. See n.2, above. Though statements of
general policy are understood to be non-binding, id., there
is some authority for the proposition that interpretive
rules should be treated differently. 3
    Commerce did make clear that this change was to be
global in nature, applicable to all future requests for an


     3  See Ronald M. Levin, Rulemaking and the Guid-
ance Exemption, Admin. L. Rev. (forthcoming 2018),
manuscript July 21, 2017, exhaustively reviewing the
authorities and urging that interpretive rules be accorded
no more weight than an agency’s general policy state-
ments.             Available             at            pa-
pers.ssrn.com/sol3/papers.cfm?abstract_id=2958267.
GLYCINE & MORE, INC.   v. UNITED STATES                11



extension of time to withdraw a previously-filed request
for review. Thereafter, parties seeking untimely with-
drawals would no longer be able to get an extension based
on what might be reasonable under the circumstances in
light of the concerns previously identified and employed
by Commerce. Instead, they would have to demonstrate
the existence of an “extraordinary circumstance” warrant-
ing an extension. Commerce applied this change in its
approach to the administrative review in this case, which
forms the basis for this appeal.
                         This Appeal
    This appeal stems from Commerce’s 1995 antidump-
ing duty order on glycine from the People’s Republic of
China, see Antidumping Duty Order: Glycine from the
People’s Republic of China, 60 Fed. Reg. 16,116 (Mar. 29,
1995), under which Commerce had imposed specified
duties on imports of Chinese glycine. On March 1, 2012,
Commerce notified interested parties of the opportunity to
request an administrative review of that order for the
period from March 1, 2011 through February 29, 2012.
See Antidumping or Countervailing Duty Order, Finding,
or Suspended Investigation; Opportunity to Request
Administrative Review, 77 Fed. Reg. 12,559 (Mar. 1,
2012).
    In announcing the opportunity to request review,
Commerce repeated the language of its 2011 Notice,
explaining that, if a party requested review, Commerce
did not intend to extend the 90-day period for withdrawal
unless the requestor demonstrated an extraordinary
circumstance that prevented it from submitting a timely
withdrawal request.
    On March 30, 2012, GEO and Baoding Mantong sepa-
rately requested an administrative review. On April 30,
2012, Commerce published notice that it had initiated an
administrative review, and in that notice, Commerce
again stated it did not intend to extend the 90-day period
12                  GLYCINE & MORE, INC.   v. UNITED STATES



for withdrawal absent a party demonstrating an extraor-
dinary circumstance. See Initiation of Antidumping and
Countervailing Duty Administrative Reviews and Request
for Revocation in Part, 77 Fed. Reg. 25,401 (Apr. 30,
2012). On July 10, 2012, Commerce selected Baoding
Mantong as one of two mandatory respondents and issued
a questionnaire to the company.
    On July 30, 2012, GEO submitted what was deter-
mined to be its timely withdrawal. 4 On August 7, 2012—
after the 90-day period had ended—Baoding Mantong
asked Commerce for an extension of the 90-day period in
which to file its withdrawal, and an extension of the
deadline for its questionnaire response. Baoding Man-
tong claimed that extraordinary circumstances existed
and asserted that it learned of GEO’s withdrawal only
after the 90-day period expired.
    Baoding Mantong explained that it did not withdraw
before learning of GEO’s withdrawal because, if GEO had
not withdrawn, then its withdrawal would have had no
effect. Baoding Mantong further explained that good
reason existed for permitting an extension of time, be-
cause Commerce would be able to preserve its resources
since Baoding had not yet submitted its questionnaire.
    On August 22, 2012, Commerce informed Baoding
Mantong that Commerce was considering its request, and
that it did not have to respond to Commerce’s question-
naire. Subsequently, Commerce informed Baoding Man-
tong that it was rejecting its untimely withdrawal
because Baoding Mantong had not demonstrated an
extraordinary circumstance warranting an extension of



     4 The 90-day period ended on July 29, 2012, but be-
cause this was a Sunday, Commerce deemed GEO’s
withdrawal timely.
GLYCINE & MORE, INC.   v. UNITED STATES                13



the 90-day period. Commerce also instructed Baoding
Mantong to respond to Commerce’s questionnaire. Bao-
ding Mantong responded in a letter dated October 18,
2012 and filed on October 19, 2012, informing Commerce
that it would not participate in the administrative review
or respond to the questionnaire. 5
    On December 6, 2012, Commerce published its Pre-
liminary Results and proposed assigning Baoding Man-
tong a 453.79% dumping duty margin based on facts
otherwise available on the record and an adverse infer-
ence due to Baoding Mantong’s refusal to respond to
Commerce’s questionnaire. See Glycine from the People’s
Republic of China: Preliminary Results, 77 Fed. Reg.
72,817 (Dec. 6, 2012). 6
    On December 17, 2012, Glycine & More entered an
appearance before Commerce and objected to Commerce’s
rejection of Baoding Mantong’s request to withdraw and
the dumping duty margin.
    On April 8, 2013, Commerce published its Final Re-
sults, assigning the same dumping margin to Baoding
Mantong based on its Preliminary Results. In its related
Issues and Decision Memorandum, Commerce rejected



   5    On October 18, 2012, Commerce published the fi-
nal results of a prior (2010–2011) administrative review
of the 1995 antidumping order and assigned Baoding
Mantong a dumping margin of 453.79% for the period
from March 1, 2010 through February 28, 2011. See
Glycine from the People’s Republic of China: Final Re-
sults of Antidumping Duty Administrative Review, 77
Fed. Reg. 64,100, 64,101 (Oct. 18, 2012).
    6   Commerce based the 453.79% rate on the prior
(2010-2011) administrative review, see J.A. 351, however,
the rate has since been modified.
14                    GLYCINE & MORE, INC.   v. UNITED STATES



the assertion that its interpretation and application of
§ 351.213(d)(1) had been inconsistent. Commerce noted
that, “[i]n the past, extending the 90-day deadline de-
pended on a variety of factors, such as whether the De-
partment had devoted significant time or resources to the
review and the stage of the review.” J.A. 663. However,
Commerce explained that it had “clarified” the deadline in
its 2011 Notice to provide parties with “‘additional cer-
tainty’” and “[t]o enhance certainty and fairness.” Id.
    Commerce rejected the argument that Baoding Man-
tong had demonstrated an extraordinary circumstance
and observed that Baoding Mantong had likely stopped
participating in the review after learning of the results of
the prior (2010–2011) administrative review, which were
published one day before Baoding Mantong’s notice end-
ing its participation was filed. Commerce further noted
that the parties knew of the preliminary and revised
preliminary results of the prior (2010–2011) administra-
tive review before the 90-day period ended.
                Proceedings Before the CIT
    On April 26, 2013, Glycine & More filed a complaint
with the CIT and eventually moved for judgment on the
agency record, arguing, inter alia, that Commerce had
violated its own regulation concerning the 90-day time
limit. Commerce and GEO opposed Glycine & More’s
motion for judgment.
    The CIT issued its opinion on November 3, 2015. In
that opinion the CIT concluded that Commerce’s interpre-
tation of its own regulation was unreasonable and that
Commerce’s rejection of Baoding Mantong’s untimely
withdrawal was improper.
    The CIT conducted a lengthy review of the relevant
regulatory history and determined that Commerce’s 2011
Notice, requiring an “extraordinary circumstance” in the
context of untimely withdrawals, did not control because
GLYCINE & MORE, INC.   v. UNITED STATES                  15



it defeated the original purpose of the regulation. The
CIT determined that Commerce’s interpretation of
§ 351.213(d)(1) was unreasonable as applied.
    The CIT observed that Baoding Mantong had not
learned of the final results of the prior administrative
review until after the 90-day deadline. The CIT also
explained that, because Baoding Mantong had sought
withdrawal before submitting its questionnaire response,
there was no evidentiary basis from which Commerce
could have concluded that it had spent considerable time
and resources on the review. The CIT remanded for
Commerce to re-decide whether Baoding Mantong’s
extension should be granted.
    In its remand, the CIT required that Commerce
“reach a new decision that does not apply the interpreta-
tion of [§ 351.213(d)(1)] adopted in 2011, which is unrea-
sonable for the reasons the [CIT] has identified, and
instead applies an interpretation that is reasonable and,
in particular, is consistent with the purpose of the regula-
tion, as stated by Commerce upon promulgation in 1989
and maintained upon re-promulgation in 1997.” Glycine
& More, Inc. v. United States, 107 F. Supp. 3d 1356, 1370
(Ct. Int’l Trade 2015).
    The CIT instructed Commerce to consider the circum-
stances including that Baoding Mantong’s request oc-
curred only days after the 90-day deadline expired; that
the review was in an early stage with no questionnaire
response being submitted; that Baoding Mantong could
not have known the final results of the prior review; and
that all parties who had requested the review wanted it
rescinded. The CIT stated that it “envisions that it could
sustain a decision reinstating the previous, negative
decision only if the record were to support a finding of a
new and compelling circumstance, not previously identi-
fied by Commerce.” Id.
16                   GLYCINE & MORE, INC.   v. UNITED STATES



    The CIT further stated that it “appears likely” that
only a decision allowing an extension of the 90-day period
and rescinding the administrative review “could fulfill the
stated purpose of § 351.213(d)(1). For although this
regulation grants [Commerce] discretion over whether to
extend the 90-day period, the compelling circumstances
giving rise to this case, when viewed according to the
purpose of the regulation, would call into question any
decision on remand reinstating the previous, challenged
decision to deny the extension.” Id.
            Commerce’s Decision on Remand
    After remand, in February 2016, Commerce filed its
Redetermination Pursuant to Court Remand Order (“Re-
determination Decision”).     In that Redetermination,
Commerce stated its intent to extend—under protest—the
deadline for Baoding Mantong to withdraw and rescind
the review, because Commerce could not find any “new
and compelling circumstance” justifying denial.
    At the same time, Commerce made clear its grounds
for protest: Commerce asserted that the CIT’s decision
unfairly and improperly ‘nullified’ Commerce’s “wide
discretion” under § 351.213(d)(1). Commerce explained
that it did not read the regulatory histories of the final
rules in 1989 and 1997 as limiting Commerce’s discretion
to account for instances in which parties were seeking to
know the final results of an immediately preceding re-
view. Commerce emphasized that, in its view, the pur-
pose of the regulation was to grant Commerce maximum
discretion in determining whether to extend the 90-day
period.
           Further Proceedings Before the CIT
    In October 2016, the CIT issued a judgment and opin-
ion affirming Commerce’s Redetermination Decision,
granting Glycine & More’s CIT Rule 56.2 motion for
judgment on the agency record, and ordering that Com-
GLYCINE & MORE, INC.   v. UNITED STATES                 17



merce take the necessary steps to rescind the administra-
tive review with respect to Baoding Mantong.
    The CIT, however, emphasized that it was not affirm-
ing all of Commerce’s statements in its decision, because
Commerce had misinterpreted the CIT’s prior decision.
In particular, the CIT explained that it did not nullify
Commerce’s discretion, and that Commerce did not have
to grant untimely requests merely because the requestor
did not know the final results of an immediately preced-
ing review. Instead, the CIT explained that, by way of
example, Commerce might deny such a request if it had
already expended considerable time and resources in the
review at issue and the requestor sought withdrawal after
concluding the results were not likely to be favorable—
even if the requestor had not learned the results of the
immediately preceding review.
                   Appeal to this Court
    GEO appeals and argues that the CIT failed to give
proper deference to Commerce’s interpretation of its own
regulation in 19 C.F.R. § 351.213(d)(1). GEO also argues
that the CIT improperly directed Commerce’s findings on
remand, while precluding Commerce from explaining or
clarifying its own interpretation. As noted, neither Com-
merce nor the United States join the appeal.
   We have jurisdiction under 28 U.S.C. § 1295(a)(5).
                         DISCUSSION
     We review the CIT’s grant of judgment upon the ad-
ministrative record without deference, except that we
review the CIT’s factual determinations for clear error.
See Ammex, Inc. v. United States, 419 F.3d 1342, 1344
(Fed. Cir. 2005). We review the CIT’s legal determina-
tions without deference. Ad Hoc Shrimp Trade Action
Comm. v. United States, 515 F.3d 1372, 1379 (Fed. Cir.
2008).
18                     GLYCINE & MORE, INC.   v. UNITED STATES



    When construing an agency regulation as a matter of
law, we use basically the same rules we would use in
construing a statute. Roberto v. Dep’t of Navy, 440 F.3d
1341, 1350 (Fed. Cir. 2006). We examine the regulation’s
language to ascertain its plain meaning. Id. We may also
consider the language of related regulations. Id. When
the regulation is unambiguous, “it is the duty of the
courts to enforce it according to its obvious terms and not
to insert words and phrases so as to incorporate therein a
new and distinct provision.” Tesoro Haw. Corp. v. United
States, 405 F.3d 1339, 1347 (Fed. Cir. 2005) (quoting
Gibson v. United States, 194 U.S. 182, 185 (1904)). If “the
plain meaning of the regulation is clear, no further in-
quiry is required into agency interpretations or the regu-
latory history to determine its meaning.” Roberto, 440
F.3d at 1350.
    On the other hand, if the regulation is deemed to be
ambiguous, then an agency’s interpretation of its own
regulation may be entitled to judicial deference, generally
described as Auer or Skidmore deference, referring to the
decisions that articulated the particular type of interpre-
tive deference owed an agency by the courts. In this case,
GEO argues that the CIT, by failing to give the agency’s
understanding of its own regulation proper deference,
erred in its first decision, an error that necessarily infect-
ed its second decision.
    Before addressing the question of how wide is the
agency’s discretion in interpreting its own regulations,
discussed at length by the appellant; and before address-
ing the consequent question of how much and what kind
of deference is owed the agency, a question which further
implicates the history of the sentence in § 351.213(d)(1),
discussed at length by the CIT in its opinions—there is a
predicate question: is this 2011 Notice ambiguous?
   The answer is no. As we have discussed, there is no
question about what Commerce intended by its 2011
GLYCINE & MORE, INC.   v. UNITED STATES                 19



Notice—the explanation given in the Notice leaves little
room for doubt—and its application to this appellant
indicates a straightforward understanding and decision-
process. And as the record establishes, this understand-
ing changes significantly what the original enactment of
the sentence was intended to do, and how it was applied,
as demonstrated by the history of the sentence itself.
    In short, the meaning of the 2011 Notice is plain, and
the difference between what the sentence at issue meant
before and after the Notice is equally plain. Before the
Notice, the regulation was understood to provide the
Secretary with wide discretion, to use judgment regarding
the facts and circumstances presented, and to apply a
reasonableness test in making the decision whether to
extend the deadline for filing a withdrawal notice. After
the 2011 Notice, only “extraordinary circumstances”
would do, and the Secretary’s discretion was to be applied
narrowly to the case, and only when an applicant for
extension could prove such extraordinary circumstances
exist. Thus, the Notice represented an incompatible
departure from the clear meaning of the regulation. It
was not simply an interpretive statement regarding an
ambiguity in the regulation or a general statement of
policy.
    Assuming Commerce wished to rewrite the regulation
in this manner, could it do so in this way? The answer is
no. Because the regulation’s meaning is clear, no defer-
ence is warranted. Deferring to Commerce’s position
“would be to permit the agency, under the guise of inter-
preting a regulation, to create de facto a new regulation.”
Christensen v. Harris Cty., 529 U.S. 576, 588 (2000)
(unambiguous regulation could not be rewritten by agency
under guise of interpreting regulation and judiciary owed
no deference to agency interpretation). If Commerce
wished to rewrite or amend the regulation, such a regula-
tion intended to have the force of law must be adopted
20                   GLYCINE & MORE, INC.   v. UNITED STATES



with notice-and-comment rulemaking, which was absent
here. See id. at 587–88.
    Since the 2011 Notice was intended to effectively re-
write the substantive meaning of the regulation without
going through the necessary notice-and-comment rule-
making, it has no legal standing, and thus provides no
basis upon which the Secretary could make his decision.
That was the ruling made by the CIT, and it is correct.
    The CIT required the Secretary to re-make the deci-
sion about the extension of time, applying the criteria
contained in the only legally applicable standard, the one
set out in § 351.213(d)(1). Applying that standard, the
Secretary granted the extension, and Baoding Mantong’s
request for review was effectively withdrawn. Com-
merce’s protest of the CIT order is unavailing, as is GEO’s
support for it.
                       CONCLUSION
     For the foregoing reasons, the judgment of the CIT is
affirmed.
                      AFFIRMED
