(Slip Opinion)              OCTOBER TERM, 2011                                       1

                                       Syllabus

         NOTE: Where it is feasible, a syllabus (headnote) will be released, as is
       being done in connection with this case, at the time the opinion is issued.
       The syllabus constitutes no part of the opinion of the Court but has been
       prepared by the Reporter of Decisions for the convenience of the reader.
       See United States v. Detroit Timber & Lumber Co., 200 U. S. 321, 337.


SUPREME COURT OF THE UNITED STATES

                                       Syllabus

  KAPPOS, UNDER SECRETARY OF COMMERCE FOR

    INTELLECTUAL PROPERTY AND DIRECTOR, 

    PATENT AND TRADEMARK OFFICE v. HYATT 


CERTIORARI TO THE UNITED STATES COURT OF APPEALS FOR
                THE FEDERAL CIRCUIT

    No. 10–1219. Argued January 9, 2012—Decided April 18, 2012
Under the Patent Act of 1952, if a Patent and Trade Office (PTO) exam-
 iner denies a patent application, 35 U. S. C. §131, the applicant may
 file an administrative appeal with the PTO’s Board of Patent Appeals
 and Interferences, §134. If the Board also denies the application, the
 applicant may appeal directly to the Court of Appeals for the Federal
 Circuit under §141. Alternatively, the applicant may file a civil ac-
 tion against the PTO Director under §145, which permits the appli-
 cant to present evidence that was not presented to the PTO.
    Respondent Hyatt filed a patent application covering multiple
 claims. The patent examiner denied all of the claims for lack of an
 adequate written description. Hyatt appealed to the Board, which
 approved some claims but denied others. Pursuant to §145, Hyatt
 filed a civil action against the Director, but the District Court de-
 clined to consider Hyatt’s newly proffered written declaration in sup-
 port of the adequacy of his description, thus limiting its review to the
 administrative record. Applying the deferential “substantial evi-
 dence” standard of the Administrative Procedure Act (APA) to the
 PTO’s factual findings, the court granted summary judgment to the
 Director. On appeal, the Federal Circuit vacated the judgment, hold-
 ing that patent applicants can introduce new evidence in §145 pro-
 ceedings, subject only to the limitations in the Federal Rules of Evi-
 dence and the Federal Rules of Civil Procedure. It also reaffirmed
 its precedent that when new, conflicting evidence is introduced, the
 district court must make de novo findings to take such evidence into
 account.
2                         KAPPOS v. HYATT

                               Syllabus

Held: There are no limitations on a patent applicant’s ability to intro-
 duce new evidence in a §145 proceeding beyond those already present
 in the Federal Rules of Evidence and the Federal Rules of Civil Pro-
 cedure. If new evidence is presented on a disputed question of fact,
 the district court must make de novo factual findings that take ac-
 count of both the new evidence and the administrative record before
 the PTO. Pp. 5−14.
    (a) Section 145, by its express terms, neither imposes unique evi-
 dentiary limits in district court proceedings nor establishes a height-
 ened standard of review for PTO factual findings. Nonetheless, the
 Director contends that background principles of administrative law
 govern the admissibility of new evidence and impose a deferential
 standard of review in §145 proceedings. As the Director concedes,
 however, judicial review in §145 proceedings is not limited to the ad-
 ministrative record because the district court may consider new evi-
 dence. If it does so, the district court must act as a factfinder and
 cannot apply the APA’s deferential standard to PTO factual findings
 when those findings are contradicted by new evidence. Moreover, the
 doctrine of administrative exhaustion―the primary purpose of which
 is “the avoidance of premature interruption of the administrative
 process,” McKart v. United States, 395 U. S. 185, 193―does not apply
 because the PTO process is complete by the time a §145 proceeding
 occurs. Pp. 5−7.
    (b) The core language of the 1870 Patent Act, codified as Revised
 Statute §4915 (R. S. 4915), remains largely unchanged in §145. Deci-
 sions interpreting R. S. 4915 thus inform this Court’s understanding
 of §145. Both Butterworth v. United States ex rel. Hoe, 112 U. S. 50,
 and Morgan v. Daniels, 153 U. S. 120, describe the nature of R. S.
 4915 proceedings, but the two opinions can be perceived as being in
 some tension. Butterworth described the proceeding as an original
 civil action seeking de novo adjudication of the merits of a patent ap-
 plication, while Morgan described it as a suit for judicial review of
 agency action under a deferential standard. The cases are distin-
 guishable, however, because they addressed different circumstances.
 Butterworth discussed a patent applicant’s challenge to the denial of
 his application, whereas Morgan involved an interference proceeding
 that would now be governed by §146, not §145, and in which no new
 evidence was presented. Here, this Court is concerned only with a
 §145 proceeding in which new evidence was presented to the District
 Court, so Butterworth guides this Court’s decision. Thus, a district
 court conducting a §145 proceeding may consider all competent evi-
 dence adduced and is not limited to considering only new evidence
 that could not have been presented to the PTO. The introduction of
 new evidence in §145 proceedings is subject only to the Federal Rules
                     Cite as: 566 U. S. ____ (2012)                     3

                                Syllabus

  of Evidence and the Federal Rules of Civil Procedure, and if new evi-
  dence is presented to the district court on a disputed factual question,
  de novo findings by the district court will be necessary for that new
  evidence to be taken into account along with the evidence before the
  Board. Pp. 7−13.
     (c) The district court may, however, consider whether the applicant
  had an opportunity to present the newly proffered evidence before the
  PTO in deciding what weight to afford that evidence. Pp. 13−14.
625 F. 3d 1320, affirmed and remanded.

  THOMAS, J., delivered the opinion for a unanimous Court. SOTO-
MAYOR, J.,
         filed a concurring opinion, in which BREYER, J., joined.
                        Cite as: 566 U. S. ____ (2012)                              1

                             Opinion of the Court

     NOTICE: This opinion is subject to formal revision before publication in the
     preliminary print of the United States Reports. Readers are requested to
     notify the Reporter of Decisions, Supreme Court of the United States, Wash-
     ington, D. C. 20543, of any typographical or other formal errors, in order
     that corrections may be made before the preliminary print goes to press.


SUPREME COURT OF THE UNITED STATES
                                   _________________

                                   No. 10–1219
                                   _________________


  DAVID J. KAPPOS, UNDER SECRETARY OF COM-

   MERCE FOR INTELLECTUAL PROPERTY AND 

    DIRECTOR, PATENT AND TRADEMARK OF- 

     FICE, PETITIONER v. GILBERT P. HYATT

 ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF

           APPEALS FOR THE FEDERAL CIRCUIT

                                 [April 18, 2012]


  JUSTICE THOMAS delivered the opinion of the Court.
  The Patent Act of 1952, 35 U. S. C. §100 et seq., grants
a patent applicant whose claims are denied by the Patent
and Trademark Office (PTO) the opportunity to challenge
the PTO’s decision by filing a civil action against the
Director of the PTO in federal district court. In such a
proceeding, the applicant may present evidence to the
district court that he did not present to the PTO. This
case requires us to consider two questions. First, we must
decide whether there are any limitations on the appli-
cant’s ability to introduce new evidence before the district
court. For the reasons set forth below, we conclude that
there are no evidentiary restrictions beyond those already
imposed by the Federal Rules of Evidence and the Federal
Rules of Civil Procedure. Second, we must determine
what standard of review the district court should apply
when considering new evidence. On this question, we hold
that the district court must make a de novo finding when
new evidence is presented on a disputed question of fact.
2                         KAPPOS v. HYATT

                         Opinion of the Court

In deciding what weight to afford that evidence, the dis-
trict court may, however, consider whether the applicant
had an opportunity to present the evidence to the PTO.
                              I
   The Patent Act of 1952 establishes the process by which
the PTO examines patent applications. A patent exam-
iner first determines whether the application satisfies the
statutory prerequisites for granting a patent. 35 U. S. C.
§131. If the examiner denies the application, the appli-
cant may file an administrative appeal with the PTO’s
Board of Patent Appeals and Interferences (Board). §134.
If the Board also denies the application, the Patent Act
gives the disappointed applicant two options for judicial
review of the Board’s decision. The applicant may either:
(1) appeal the decision directly to the United States Court
of Appeals for the Federal Circuit, pursuant to §141; or (2)
file a civil action against the Director of the PTO in the
United States District Court for the District of Columbia
pursuant to §145.1
   In a §141 proceeding, the Federal Circuit must review
the PTO’s decision on the same administrative record that
was before the PTO. §144. Thus, there is no opportunity
for the applicant to offer new evidence in such a proceed-
ing. In Dickinson v. Zurko, 527 U. S. 150 (1999), we ad-
——————
  1 On September 16, 2011, the President signed the Leahy-Smith

America Invents Act, 125 Stat. 284, into law. That Act made signifi-
cant changes to Title 35 of the United States Code, some of which are
related to the subject matter of this case. For example, the Act changed
the venue for §145 actions from the United States District Court for the
District of Columbia to the United States District Court for the East-
ern District of Virginia, id., at 316, changed the name of the Board
of Patent Appeals and Interferences to the Patent Trial and Appeal
Board, id., at 290, and changed the name of interferences to derivation
proceedings, ibid. Neither party contends that the Act has any effect
on the questions before us, and all references and citations in this
opinion are to the law as it existed prior to the Act.
                 Cite as: 566 U. S. ____ (2012)            3

                     Opinion of the Court

dressed the standard that governs the Federal Circuit’s
review of the PTO’s factual findings. We held that the
Administrative Procedure Act (APA), 5 U. S. C. §701
et seq., applies to §141 proceedings and that the Federal
Circuit therefore should set aside the PTO’s factual find-
ings only if they are “ ‘unsupported by substantial evi-
dence.’ ” 527 U. S., at 152 (quoting 5 U. S. C. §706).
   In Zurko, we also noted that, unlike §141, §145 permits
the applicant to present new evidence to the district court
that was not presented to the PTO. 527 U. S., at 164.
This opportunity to present new evidence is significant,
not the least because the PTO generally does not accept
oral testimony. See Brief for Petitioner 40, n. 11. We have
not yet addressed, however, whether there are any limita-
tions on the applicant’s ability to introduce new evidence
in such a proceeding or the appropriate standard of review
that a district court should apply when considering such
evidence.
                             II
   In 1995, respondent Gilbert Hyatt filed a patent appli-
cation that, as amended, included 117 claims. The PTO’s
patent examiner denied each claim for lack of an adequate
written description. See 35 U. S. C. §112 (requiring pat-
ent applications to include a “specification” that provides,
among other information, a written description of the
invention and of the manner and process of making and
using it). Hyatt appealed the examiner’s decision to the
Board, which eventually approved 38 claims, but denied
the rest. Hyatt then filed a §145 action in Federal Dis-
trict Court against the Director of the PTO (Director), peti-
tioner here.
   To refute the Board’s conclusion that his patent applica-
tion lacked an adequate written description, Hyatt sub-
mitted a written declaration to the District Court. In the
declaration, Hyatt identified portions of the patent specifi-
4                     KAPPOS v. HYATT

                      Opinion of the Court

cation that, in his view, supported the claims that the
Board held were not patentable. The District Court de-
termined that it could not consider Hyatt’s declaration
because applicants are “ ‘precluded from presenting new is-
sues, at least in the absence of some reason of justice put
forward for failure to present the issue to the Patent Of-
fice.’ ” Hyatt v. Dudas, Civ. Action No. 03–0901 (D DC,
Sept. 30, 2005), p. 9, App. to Pet. for Cert. 182a (quoting
DeSeversky v. Brenner, 424 F. 2d 857, 858 (CADC 1970)).
Because the excluded declaration was the only additional
evidence submitted by Hyatt in the §145 proceeding, the
evidence remaining before the District Court consisted
entirely of the PTO’s administrative record. Therefore,
the District Court reviewed all of the PTO’s factual find-
ings under the APA’s deferential “substantial evidence”
standard. See supra, at 2; see also Mazzari v. Rogan, 323
F. 3d 1000, 1004–1005 (CA Fed. 2003). Applying that
standard, the District Court granted summary judgment
to the Director.
   Hyatt appealed to the Federal Circuit. A divided panel
affirmed, holding that the APA imposed restrictions on the
admission of new evidence in a §145 proceeding and that
the district court’s review is not “wholly de novo.” Hyatt v.
Doll, 576 F. 3d 1246, 1269–1270 (2009). The Federal
Circuit granted rehearing en banc and vacated the District
Court’s grant of summary judgment. The en banc court
first held “that Congress intended that applicants would
be free to introduce new evidence in §145 proceedings
subject only to the rules applicable to all civil actions, the
Federal Rules of Evidence and the Federal Rules of Civil
Procedure,” even if the applicant had no justification for
failing to present the evidence to the PTO. 625 F. 3d 1320,
1331 (2010). Reaffirming its precedent, the court also held
that when new, conflicting evidence is introduced in a
§145 proceeding, the district court must make de
novo findings to take such evidence into account. Id., at
                  Cite as: 566 U. S. ____ (2012)            5

                      Opinion of the Court

1336. We granted certiorari, 564 U. S. ___ (2011), and now
affirm.
                              III
  The Director challenges both aspects of the Federal
Circuit’s decision. First, the Director argues that a district
court should admit new evidence in a §145 action only if
the proponent of the evidence had no reasonable oppor-
tunity to present it to the PTO in the first instance. Se-
cond, the Director contends that, when new evidence is
introduced, the district court should overturn the PTO’s fac-
tual findings only if the new evidence clearly establishes
that the agency erred. Both of these arguments share
the premise that §145 creates a special proceeding that is
distinct from a typical civil suit filed in federal district
court and that is thus governed by a different set of proce-
dural rules. To support this interpretation of §145, the
Director relies on background principles of administrative
law and pre-existing practice under a patent statute that
predated §145. For the reasons discussed below, we find
that neither of these factors justifies a new evidentiary
rule or a heightened standard of review for factual find-
ings in §145 proceedings.
                             A
  To address the Director’s challenges, we begin with the
text of §145. See, e.g., Magwood v. Patterson, 561 U. S.
___, ___ (2010) (slip op., at 10). Section 145 grants a
disappointed patent applicant a “remedy by civil action
against the Director.” The section further explains that
the district court “may adjudge that such applicant is
entitled to receive a patent for his invention, as specified
in any of his claims involved in the decision of the [PTO],
as the facts in the case may appear and such adjudication
shall authorize the Director to issue such patent on com-
pliance with the requirements of law.” By its terms, §145
6                     KAPPOS v. HYATT

                      Opinion of the Court

neither imposes unique evidentiary limits in district court
proceedings nor establishes a heightened standard of re-
view for factual findings by the PTO.
                              B
   In the absence of express support for his position in the
text of §145, the Director argues that the statute should
be read in light of traditional principles of administrative
law, which Congress codified in the APA. The Director
notes that §145 requires a district court to review the
reasoned decisionmaking of the PTO, an executive agency
with specific authority and expertise. Accordingly, the
Director contends that a district court should defer to the
PTO’s factual findings. The Director further contends
that, given the traditional rule that a party must exhaust
his administrative remedies, a district court should con-
sider new evidence only if the party did not have an oppor-
tunity to present it to the agency.
   We reject the Director’s contention that background
principles of administrative law govern the admissibility
of new evidence and require a deferential standard of
review in a §145 proceeding. Under the APA, judicial
review of an agency decision is typically limited to the
administrative record. See 5 U. S. C. §706. But, as the
Director concedes, §145 proceedings are not so limited,
for the district court may consider new evidence. When the
district court does so, it must act as a factfinder. Zurko,
527 U. S., at 164. In that role, it makes little sense for the
district court to apply a deferential standard of review
to PTO factual findings that are contradicted by the new
evidence. The PTO, no matter how great its authority or
expertise, cannot account for evidence that it has never
seen. Consequently, the district court must make its own
findings de novo and does not act as the “reviewing court”
envisioned by the APA. See 5 U. S. C. §706.
   We also conclude that the principles of administrative
                 Cite as: 566 U. S. ____ (2012)            7

                     Opinion of the Court

exhaustion do not apply in a §145 proceeding. The Direc-
tor argues that applicants must present all available
evidence to the PTO to permit the PTO to develop the
necessary facts and to give the PTO the opportunity to
properly apply the Patent Act in the first instance. Brief
for Petitioner 21–22 (citing McKart v. United States, 395
U. S. 185, 193–194 (1969)). But as this Court held in
McKart, a primary purpose of administrative exhaustion
“is, of course, the avoidance of premature interruption of
the administrative process.” Id., at 193. That rationale
does not apply here because, by the time a §145 proceed-
ing occurs, the PTO’s process is complete. Section 145,
moreover, does not provide for remand to the PTO to
consider new evidence, and there is no pressing need for
such a procedure because a district court, unlike a court of
appeals, has the ability and the competence to receive new
evidence and to act as a factfinder. In light of these as-
pects of §145 proceedings—at least in those cases in which
new evidence is presented to the district court on a dis-
puted question of fact—we are not persuaded by the Direc-
tor’s suggestion that §145 proceedings are governed by the
deferential principles of agency review.
                              C
   Having concluded that neither the statutory text nor
background principles of administrative law support an
evidentiary limit or a heightened standard of review for
factual findings in §145 proceedings, we turn to the evi-
dentiary and procedural rules that were in effect when
Congress enacted §145 in 1952. Although §145 is a rela-
tively modern statute, the language in that provision
originated in the Act of July 8, 1870 (1870 Act), ch. 230, 16
Stat. 198, and the history of §145 proceedings can be
traced back to the Act of July 4, 1836 (1836 Act), ch. 357, 5
Stat. 117. Thus, we begin our inquiry with the 1836 Act,
which established the Patent Office, the PTO’s predeces-
8                        KAPPOS v. HYATT

                         Opinion of the Court

sor, and first authorized judicial review of its decisions.
                               1
   The 1836 Act provided that a patent applicant could
bring a bill in equity in federal district court if his applica-
tion was denied on the ground that it would interfere
with another patent. Id., at 123–124; see also B. Ship-
man, Handbook of the Law of Equity Pleading §§101–103,
pp. 168–171 (1897). Three years later, Congress expanded
that provision, making judicial review available whenever
a patent was refused on any ground. Act of Mar. 3, 1839
(1839 Act), 5 Stat. 354. Pursuant to these statutes, any
disappointed patent applicant could file a bill in equity to
have the district court “adjudge” whether the applicant
was “entitled, according to the principles and provisions
of [the Patent Act], to have and receive a patent for his
invention.” 1836 Act, 5 Stat. 124.
   In 1870, Congress amended the Patent Act again, add-
ing intermediate layers of administrative review and in-
troducing language describing the proceeding in the
district court. 16 Stat. 198. Under the 1870 Act, an appli-
cant denied a patent by the primary examiner could ap-
peal first to a three-member board of examiners-in-chief,
then to the Commissioner for Patents, and finally to an en
banc sitting of the Supreme Court of the District of Co-
lumbia.2 Id., at 205. Notably, Congress described that
court’s review as an “appeal” based “on the evidence pro-
duced before the commissioner.” Ibid. The 1870 Act
preserved the prior remedy of a bill in equity in district
court for the applicant whose appeal was denied either by
——————
   2 The Supreme Court of the District of Columbia was a trial court

created by Congress in 1863. Act of Mar. 3, 1863, ch. 91, 12 Stat. 762.
Although the court was generally one of first instance, it also func-
tioned as an appellate court when it sat en banc. Voorhees, The Dis-
trict of Columbia Courts: A Judicial Anomaly, 29 Cath. U. L. Rev. 917,
923 (1980).
                 Cite as: 566 U. S. ____ (2012)           9

                     Opinion of the Court

the Commissioner or by the Supreme Court of the District
of Columbia. Ibid. The district court, in a proceeding that
was distinct from the appeal considered on the adminis-
trative record by the Supreme Court of the District of
Columbia, would “adjudge” whether the applicant was
“entitled, according to law, to receive a patent for his
invention . . . as the facts in the case may appear.” Ibid.
In 1878, Congress codified this provision of the 1870 Act
as Revised Statute §4915 (R. S. 4915). That statute was
the immediate predecessor to §145, and its core language
remains largely unchanged in §145. Accordingly, both
parties agree that R. S. 4915 and the judicial decisions
interpreting that statute should inform our understanding
of §145.
                              2
   This Court described the nature of R. S. 4915 proceed-
ings in two different cases: Butterworth v. United States ex
rel. Hoe, 112 U. S. 50 (1884), and Morgan v. Daniels, 153
U. S. 120 (1894). In Butterworth, the Court held that the
Secretary of the Interior, the head of the federal depart-
ment in which the Patent Office was a bureau, had no
authority to review a decision made by the Commissioner
of Patents in an interference proceeding. In its discussion,
the Court described the remedy provided by R. S. 4915 as
    “a proceeding in a court of the United States having
    original equity jurisdiction under the patent laws, ac-
    cording to the ordinary course of equity practice and
    procedure. It is not a technical appeal from the
    Patent-Office, like that authorized [before the Su-
    preme Court of the District of Columbia], confined to
    the case as made in the record of that office, but is
    prepared and heard upon all competent evidence ad-
    duced and upon the whole merits.” 112 U. S., at 61.
The Butterworth Court also cited several lower court
10                   KAPPOS v. HYATT

                     Opinion of the Court

cases, which similarly described R. S. 4915 proceedings
as “altogether independent” from the hearings before the
Patent Office and made clear that the parties were “at
liberty to introduce additional evidence” under “the rules
and practice of a court of equity.” In re Squire, 22 F. Cas.
1015, 1016 (No. 13,269) (CC ED Mo. 1877); see also Whip-
ple v. Miner, 15 F. 117, 118 (CC Mass. 1883) (describing
the federal court’s jurisdiction in an R. S. 4915 proceeding
as “an independent, original jurisdiction”); Butler v. Shaw,
21 F. 321, 327 (CC Mass. 1884) (holding that “the court
may receive new evidence, and has the same powers as in
other cases in equity”).
   Ten years later, in Morgan, this Court again confronted
a case involving proceedings under R. S. 4915. 153 U. S.
120. There, a party challenged a factual finding by the
Patent Office, but neither side presented additional evi-
dence in the District Court. Id., at 122–123. This Court
described the parties’ dispute as one over a question of
fact that had already “been settled by a special tribunal
[e]ntrusted with full power in the premises” and charac-
terized the resulting District Court proceeding not as an
independent civil action, but as “something in the nature
of a suit to set aside a judgment.” Id., at 124. Consistent
with that view, the Court held that the agency’s findings
should not be overturned by “a mere preponderance of
evidence.” Ibid.
   Viewing Butterworth and Morgan together, one might
perceive some tension between the two cases. Butterworth
appears to describe an R. S. 4915 proceeding as an original
civil action, seeking de novo adjudication of the merits of
a patent application. Morgan, on the other hand, appears
to describe an R. S. 4915 proceeding as a suit for judicial
review of agency action, governed by a deferential stand-
ard of review. To resolve that apparent tension, the Direc-
tor urges us to disregard the language in Butterworth as
mere dicta and to follow Morgan. He argues that Butter-
                     Cite as: 566 U. S. ____ (2012)                  11

                         Opinion of the Court

worth “shed[s] no light on the extent to which new evi-
dence was admissible in R. S. 4915 proceedings or on the
standard of review that applied in such suits.” Brief for
Petitioner 33. The Director maintains that Morgan, in
contrast, firmly established that a district court in such
a proceeding performs a deferential form of review, gov-
erned by traditional principles of administrative law. We
reject the Director’s position.3
   We think that the differences between Butterworth and
Morgan are best explained by the fact that the two cases
addressed different circumstances. Butterworth discussed
the character of an R. S. 4915 proceeding in which a dis-
appointed patent applicant challenged the Board’s denial
of his application. Although that discussion was not
strictly necessary to Butterworth’s holding it was also not
the kind of ill-considered dicta that we are inclined to ignore.
The Butterworth Court carefully examined the various pro-
visions providing relief from the final denial of a patent
application by the Commissioner of Patents to determine
that the Secretary of the Interior had no role to play in
that process. 112 U. S., at 59–64. The Court further
surveyed the decisions of the lower courts with regard to
the nature of an R. S. 4915 proceeding and concluded that
its view was “the uniform and correct practice in the Cir-
cuit Courts.” Id., at 61. We note that this Court reiter-
ated Butterworth’s well-reasoned interpretation of R. S.
4915 in three later cases.4
——————
  3 Both parties cite additional cases from the lower courts that they

claim support their view of the statute, but these cases are too diverse
to support any firm inferences about Congress’ likely intent in enacting
§145.
  4 In Gandy v. Marble, 122 U. S. 432 (1887), the Court described an

R. S. 4915 proceeding as “a suit according to the ordinary course of
equity practice and procedure” rather than a “technical appeal from
the Patent Office.” Id., at 439 (citing Butterworth, 112 U. S., at 61).
Likewise, in In re Hien, 166 U. S. 432 (1897), the Court distinguished
an R. S. 4915 proceeding from the “ ‘technical appeal from the Patent
12                         KAPPOS v. HYATT

                          Opinion of the Court

   Morgan, on the other hand, concerned a different situa-
tion from the one presented in this case. First, Morgan
addressed an interference proceeding. See 153 U. S., at
125 (emphasizing that “the question decided in the Pat-
ent Office is one between contesting parties as to priority of
invention”). Although interference proceedings were pre-
viously governed by R. S. 4915, they are now governed
by a separate section of the Patent Act, 35 U. S. C. §146,
and therefore do not implicate §145. In addition, Morgan
did not involve a proceeding in which new evidence was
presented to the District Court. See 153 U. S., at 122
(stating that the case “was submitted, without any addi-
tional testimony, to the Circuit Court”).
                              3
  Because in this case we are concerned only with §145
proceedings in which new evidence has been presented
to the District Court, Butterworth rather than Morgan
guides our decision. In Butterworth, this Court observed
that an R. S. 4915 proceeding should be conducted “accord-
ing to the ordinary course of equity practice and proce-
dure” and that it should be “prepared and heard upon all
competent evidence adduced and upon the whole merits.”
112 U. S., at 61. Likewise, we conclude that a district
court conducting a §145 proceeding may consider “all com-
petent evidence adduced,” id., at 61, and is not limited to
considering only new evidence that could not have been
presented to the PTO. Thus, we agree with the Federal
Circuit that “Congress intended that applicants would be
free to introduce new evidence in §145 proceedings subject
only to the rules applicable to all civil actions, the Federal
——————
Office’ ” authorized under R. S. 4911, the predecessor to current §141.
Id., at 439 (quoting Butterworth, supra, at 61). And, finally, in Hoover
Co. v. Coe, 325 U. S. 79 (1945), the Court cited Butterworth to support
its description of an R. S. 4915 proceeding as a “formal trial.” 325 U. S.,
at 83, and n. 4.
                  Cite as: 566 U. S. ____ (2012)           13

                      Opinion of the Court

Rules of Evidence and the Federal Rules of Civil Proce-
dure.” 625 F. 3d, at 1331.
   We also agree with the Federal Circuit’s longstanding
view that, “where new evidence is presented to the district
court on a disputed fact question, a de novo finding will be
necessary to take such evidence into account together with
the evidence before the board.” Fregeau v. Mossinghoff,
776 F. 2d 1034, 1038 (1985). As we noted in Zurko,
the district court acts as a factfinder when new evidence
is introduced in a §145 proceeding. 527 U. S., at 164. The
district court must assess the credibility of new witnesses
and other evidence, determine how the new evidence
comports with the existing administrative record, and
decide what weight the new evidence deserves. As a
logical matter, the district court can only make these
determinations de novo because it is the first tribunal to
hear the evidence in question. Furthermore, a de novo
standard adheres to this Court’s instruction in Butter-
worth that an R. S. 4915 proceeding be heard “upon the
whole merits” and conducted “according to the ordinary
course of equity practice and procedure.” 112 U. S., at 61.
                             D
   Although we reject the Director’s proposal for a stricter
evidentiary rule and an elevated standard of review in
§145 proceedings, we agree with the Federal Circuit that
the district court may, in its discretion, “consider the
proceedings before and findings of the Patent Office in
deciding what weight to afford an applicant’s newly-
admitted evidence.” 625 F. 3d, at 1335. Though the PTO
has special expertise in evaluating patent applications,
the district court cannot meaningfully defer to the PTO’s
factual findings if the PTO considered a different set of
facts. Supra, at 8; cf. Microsoft Corp. v. i4i Ltd. Partner-
ship, 564 U. S. ___, ___ (2011) (slip op., at 19) (noting that
“if the PTO did not have all material facts before it, its
14                    KAPPOS v. HYATT

                      Opinion of the Court

considered judgment may lose significant force”). For this
reason, we conclude that the proper means for the district
court to accord respect to decisions of the PTO is through
the court’s broad discretion over the weight to be given to
evidence newly adduced in the §145 proceedings.
   The Director warns that allowing the district court
to consider all admissible evidence and to make de novo
findings will encourage patent applicants to withhold
evidence from the PTO intentionally with the goal of pre-
senting that evidence for the first time to a nonexpert
judge. Brief for Petitioner 23. We find that scenario
unlikely. An applicant who pursues such a strategy would
be intentionally undermining his claims before the PTO on
the speculative chance that he will gain some advantage
in the §145 proceeding by presenting new evidence to a
district court judge.
                            IV
   For these reasons, we conclude that there are no limita-
tions on a patent applicant’s ability to introduce new
evidence in a §145 proceeding beyond those already pre-
sent in the Federal Rules of Evidence and the Federal
Rules of Civil Procedure. Moreover, if new evidence is
presented on a disputed question of fact, the district court
must make de novo factual findings that take account
of both the new evidence and the administrative record
before the PTO. In light of these conclusions, the Federal
Circuit was correct to vacate the judgment of the District
Court, which excluded newly presented evidence under the
view that it “need not consider evidence negligently sub-
mitted after the end of administrative proceedings.” Civ.
Action No. 03–0901, at 15, App. to Pet. for Cert. 189a.
   The judgment is affirmed, and the case is remanded to
the Court of Appeals for further proceedings consistent
with this opinion.
                                             It is so ordered.
                  Cite as: 566 U. S. ____ (2012)            1

                   SOTOMAYOR, J., concurring

SUPREME COURT OF THE UNITED STATES
                          _________________

                          No. 10–1219
                          _________________


  DAVID J. KAPPOS, UNDER SECRETARY OF COM-

   MERCE FOR INTELLECTUAL PROPERTY AND 

    DIRECTOR, PATENT AND TRADEMARK OF- 

     FICE, PETITIONER v. GILBERT P. HYATT

 ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF

           APPEALS FOR THE FEDERAL CIRCUIT

                         [April 18, 2012] 


   JUSTICE SOTOMAYOR, with whom JUSTICE BREYER joins,
concurring.
    As the Court today recognizes, a litigant in a 35 U. S. C.
§145 proceeding is permitted to introduce evidence not
presented to the Patent and Trademark Office (PTO)
“ ‘according to the ordinary course of equity practice and
procedure.’ ” Ante, at 9 (quoting Butterworth v. United
States ex rel. Hoe, 112 U. S. 50, 61 (1884)). Dating back
to §145’s original predecessor, Congress contemplated that
courts would manage such actions “according to the course
and principles of courts of equity.” Act of July 4, 1836,
ch. 357, §17, 5 Stat. 124. And this Court and other courts
have acknowledged and applied that principle on numer-
ous occasions. See, e.g., Gandy v. Marble, 122 U. S. 432,
439 (1887) (describing Rev. Stat. 4915 (R. S. 4915) pro-
ceeding as “a suit according to the ordinary course of
equity practice and procedure”); In re Hien, 166 U. S. 432,
438 (1897) (same); In re Squire, 22 F. Cas. 1015, 1016 (No.
13,269) (CC ED Mo. 1877) (in an R. S. 4915 proceeding,
the parties were “at liberty to introduce additional evi-
dence” under “the rules and practice of a court of equity”);
ante, at 10, 12, n. 4 (citing same cases).
    Consistent with ordinary equity practice and procedure,
2                     KAPPOS v. HYATT

                   SOTOMAYOR, J., concurring

there may be situations in which a litigant’s conduct
before the PTO calls into question the propriety of admit-
ting evidence presented for the first time in a §145 pro-
ceeding before a district court. The most well-known
example was presented in Barrett Co. v. Koppers Co., 22 F.
2d 395, 396 (CA3 1927), a case in which the Barrett Com-
pany, during proceedings before the Patent Office, “ex-
pressly refused to disclose and to allow their witnesses
to answer questions” essential to establishing the priority
of its invention. After the Patent Office ruled against it,
the Barrett Company attempted to present in a subsequent
R. S. 4915 proceeding “the very subject-matter concerning
which . . . witnesses for the [patent] application were
asked questions and the Barrett Company forbade them to
answer.” Id., at 396. The Third Circuit understandably
found the Barrett Company estopped from introducing
evidence that it had “purposely” withheld from prior fact-
finders, lest the company be allowed “to profit by [its] own
. . . wrong doing.” Id., at 397. See also Dowling v. Jones,
67 F. 2d 537, 538 (CA2 1933) (L. Hand, J.) (describing
Barrett as a case in which “the Third Circuit refused to
consider evidence which the inventor had deliberately
suppressed”).
    For the reasons the Court articulates, §145 proceedings
are not limited to the administrative record developed be-
fore the PTO and applicants are entitled to present new
evidence to the district court. Accordingly, as Judge
Hand suggested, a court’s equitable authority to exclude
evidence in such proceedings is limited, and must be
exercised with caution. See Dowling, 67 F. 2d, at 538
(describing as “doubtful” the proposition that a court should
exclude evidence that was “not suppressed, but merely
neglected” before the Patent Office). Thus, when a patent
applicant fails to present evidence to the PTO due to
ordinary negligence, a lack of foresight, or simple attorney
error, the applicant should not be estopped from present-
                 Cite as: 566 U. S. ____ (2012)            3

                   SOTOMAYOR, J., concurring

ing the evidence for the first time in a §145 proceeding.
  Because there is no suggestion here that the applicant’s
failure to present the evidence in question to the PTO was
anything other than the product of negligence or a lack
of foresight, I agree that the applicant was entitled to
present his additional evidence to the District Court. But
I do not understand today’s decision to foreclose a district
court’s authority, consistent with “ ‘the ordinary course of
equity practice and procedure,’ ” ante, at 13 (quoting But-
terworth, 112 U. S., at 61), to exclude evidence “deliber-
ately suppressed” from the PTO or otherwise withheld in
bad faith. For the reasons set out by the Court, see ante, at
13–14, an applicant has little to gain by such tactics; such
cases will therefore be rare. In keeping with longstanding
historical practice, however, I understand courts to retain
their ordinary authority to exclude evidence from a §145
proceeding when its admission would be inconsistent with
regular equity practice and procedure.
  With those observations, I join the Court’s opinion in
full.
