  United States Court of Appeals
      for the Federal Circuit
                ______________________

   DIAMOND COATING TECHNOLOGIES, LLC,
             Plaintiff-Appellant

        FEDERAL-MOGUL CORPORATION,
             Third Party Defendant

                           v.

 HYUNDAI MOTOR AMERICA, HYUNDAI MOTOR
  COMPANY, KIA MOTORS AMERICA, INC., KIA
 MOTORS COMPANY, NISSAN NORTH AMERICA,
       INC., NISSAN MOTOR CO. LTD.,
              Defendants-Appellees
             ______________________

                 2015-1844, 2015-1861
                ______________________

   Appeals from the United States District Court for the
Central District of California in Nos. 8:13-cv-01480-GHK-
DFM, 8:13-cv-01481-GHK-DFM, Judge George H. King.
                 ______________________

                Decided: May 17, 2016
                ______________________

    JOSEPH SAMUEL GRINSTEIN, Susman Godfrey LLP,
Houston, TX, argued for plaintiff-appellant. Also repre-
sented    by  COLIN MICHAEL         WATTERSON; OLEG
ELKHUNOVICH, KATHRYN HOEK, MARC M. SELTZER, Los
Angeles, CA.
2               DIAMOND COATING TECHS., LLC   v. HYUNDAI MOTOR AM.



    REGINALD J. HILL, Jenner & Block LLP, Chicago, IL,
argued for all defendants-appellees.        Defendants-
appellees Nissan North America, Inc., Nissan Motor Co.
Ltd. also represented by PETER J. BRENNAN, CHAD J. RAY;
ADAM G. UNIKOWSKY, Washington, DC.

    DANIEL TALLITSCH, Baker & McKenzie LLP, Chicago,
IL, for defendants-appellees Hyundai Motor America,
Hyundai Motor Company, Kia Motors America, Inc., Kia
Motors Company. Also represented by D. JAMES PAK, San
Francisco, CA.
                ______________________

    Before WALLACH, BRYSON, and TARANTO, Circuit Judges.
WALLACH, Circuit Judge.
    Appellant Diamond Coating Technologies, LLC (“Di-
amond”) sued Appellees Hyundai Motor America, Hyun-
dai Motor Company, Kia Motors America, Inc., Kia
Motors Company, Nissan North America, Inc., and Nissan
Motor Co. Ltd. (collectively, “Appellees”) in the United
States District Court for the Central District of California
(“District Court”) alleging infringement of U.S. Patent
Nos. 6,066,399 and 6,354,008 (together, the “patents-in-
suit”). The District Court dismissed the actions because it
found that agreements between Diamond and Sanyo
Electric Co., Ltd. (“Sanyo”), the original assignee of the
patents-in-suit, did not confer patentee status on Dia-
mond, allowing Diamond to sue Appellees without joining
Sanyo. Diamond Coating Techs., LLC v. Hyundai Motor
Am., Nos. 8:13-cv-01480-MRP, 8:13-cv-01481-MRP(DFM),
2015 WL 2088892, at *6 (C.D. Cal. Apr. 1, 2015). The
District Court subsequently held that nunc pro tunc
agreements executed by Diamond and Sanyo after its
decision in Diamond did not affect its determination. J.A.
12 (order denying reconsideration).
DIAMOND COATING TECHS., LLC   v. HYUNDAI MOTOR AM.        3



    Diamond appeals the District Court’s dismissals. We
have jurisdiction pursuant to 28 U.S.C. § 1295(a)(1)
(2012). For the reasons provided below, we affirm.
                         DISCUSSION
                   I. Standard of Review
    Whether a party is a patentee able to sue another for
patent infringement raises “a question of law that this
court reviews de novo, applying Federal Circuit prece-
dent.” WiAV Sols. LLC v. Motorola, Inc., 631 F.3d 1257,
1263 (Fed. Cir. 2010) (citation omitted).
  II. Diamond Cannot Sue Alone Unless It Received All
         Substantial Rights in the Patents-in-Suit
     “A patentee shall have remedy by civil action for in-
fringement of his patent.” 35 U.S.C. § 281 (2012) (empha-
sis added). A “‘patentee’ includes not only the patentee to
whom the patent was issued but also the successors in
title to the patentee.” Id. § 100(d). A party may become
the successor-in-title to the patentee. Id. § 261, ¶ 2
(“[P]atents, or any interest therein, shall be assignable in
law by an instrument in writing.”).
    In 2011, Diamond and Sanyo signed the Patent As-
signment and Transfer Agreement (“PATA”) (J.A. 199–
232) and the Ancillary Agreement (J.A. 246–56). 1 When
the patents-in-suit issued, the inventors assigned the


    1   In their submissions, the parties designated the
entire PATA and Ancillary Agreement as confidential.
However, during oral argument, Diamond agreed to waive
any claim of confidentiality at the court’s request. See
Oral Argument at 3:44–4:49, available at http://oralargum
ents.cafc.uscourts.gov/default.aspx?fl=2015-1844.mp3.
Accordingly, we treat the terms of the PATA and Ancil-
lary Agreement as public, including any such terms that
accompany the parties’ arguments in their briefs.
4              DIAMOND COATING TECHS., LLC   v. HYUNDAI MOTOR AM.



patents to Sanyo. J.A. 82, 141. Sanyo then conveyed to
Diamond various rights to and interests in the patents-in-
suit via the PATA. J.A. 199–232.
    Diamond alleges the PATA provides Diamond with
“legal title [to] the patents-in-suit,” Appellant’s Br. 14,
such that it is the successor-in-title to the patents-in-suit,
see id. at 16–17. Because it is the successor-in-title to the
patents-in-suit, Diamond continues, it meets the defini-
tion of “patentee” under 35 U.S.C. § 281. See id. And
because it is a patentee under § 281, Diamond argues that
it may sue Appellees without joining Sanyo. Id.
    Agreements transferring patent rights occur by as-
signment or license. “An assignment of patent rights
operates to transfer title to the patent, while a license
leaves title in the patent owner” and transfers something
less than full title and rights. Minco, Inc. v. Combustion
Eng’g, Inc., 95 F.3d 1109, 1116 (Fed. Cir. 1996) (citation
omitted). “To create an assignment, a contract must
transfer: (1) the entire exclusive patent right, (2) an
undivided interest[2] in the patent rights, or (3) the entire
exclusive right within any geographical region of the
United States.” Id. at 1117 (citation omitted). “An
agreement that does not transfer one of these three inter-
ests is merely a license.” Id. (citation omitted).
     We treat an agreement granting patent rights as a
contract and interpret its terms consistent with the choice
of law provision in the agreement in question. See Alfred
E. Mann Found. for Sci. Research v. Cochlear Corp., 604



    2   “When . . . multiple inventors are listed on the
face of the patent, each co-owner presumptively owns a
pro rata undivided interest in the entire patent, no matter
what their respective contributions.”       Isr. Bio-Eng’g
Project v. Amgen, Inc., 475 F.3d 1256, 1263 (Fed. Cir.
2007) (internal quotation marks and citation omitted).
DIAMOND COATING TECHS., LLC   v. HYUNDAI MOTOR AM.          5



F.3d 1354, 1359 (Fed. Cir. 2010). The PATA states that
New York law governs the interpretation of its terms, J.A.
219, and under that law we review the District Court’s
interpretation of the PATA de novo, Dreisinger v. Teglasi,
13 N.Y.S.3d 432, 435 (App. Div. 2015).
    In this case, Diamond asserts “patentee” status only
as the alleged recipient of “the entire exclusive patent
right” (not an undivided interest or a geographically
limited entire exclusive right). On its face, “the entire
exclusive patent right” must include all substantial rights
in the patent. We have not allowed labels to control by
treating bare formalities of “title” transfer as sufficient to
determine that an “assignment” of the entire exclusive
right has occurred. Rather, we have explained that, “[t]o
determine whether a provision in an agreement consti-
tutes an assignment or license, one must . . . examine the
substance of what was granted.” Vaupel Textilmaschinen
KG v. Meccanica Euro Italia S.p.A., 944 F.2d 870, 874
(Fed. Cir. 1991); see Waterman v. Mackenzie, 138 U.S.
252, 256 (1891); Prima Tek II, L.L.C. v. A-Roo Co., 222
F.3d 1372, 1378 (Fed. Cir. 2000).
    We therefore must ask whether Diamond received all
substantial rights in the patents-in-suit or, instead,
whether Sanyo retained substantial rights. Unless Dia-
mond received all substantial rights in the patents-in-suit
at the time it filed suit in the District Court, it was not a
“patentee” (allegedly without a joint owner). If Diamond
was not a patentee, it could not bring this suit by itself.
And since Diamond did not take the opportunity provided
by the District Court to join Sanyo, the District Court
properly dismissed the suit. See, e.g., Alfred E. Mann, 604
F.3d at 1360.
 III. At the Time of Suit, Diamond Did Not Have All Sub-
           stantial Rights in the Patents-in-Suit
    The District Court held that the PATA did not convey
all substantial rights in the patents-in-suit to Diamond.
6              DIAMOND COATING TECHS., LLC   v. HYUNDAI MOTOR AM.



Diamond, 2015 WL 2088892, at *5–6. In particular, it
held that the following terms of the PATA weighed
against finding a transfer of substantial rights: (1) Dia-
mond could not assign the PATA to another party without
Sanyo’s consent; (2) Sanyo retains an economic interest in
future proceeds, including any that arise from infringe-
ment litigation; (3) “Sanyo retains a license to make, use,
and sell products covered by the patents-in-suit”; and (4)
“Sanyo retains significant control over the decision to
enforce the patents” because the PATA “condition[s]
enforcement on consideration of the best interests of
[Diamond] and Sanyo.” Id. at *5 (internal quotation
marks and citation omitted).
     Diamond challenges these findings. 3 It argues that
“[t]he PATA vests [Diamond] with the sole right to ex-
clude others,” Appellant’s Br. 19; “[n]othing in the PATA
divests [Diamond]’s sole right to sue,” id. at 21; “[Dia-
mond] could assign or sell the patents-in-suit,” id. at 23;
“Sanyo’s economic interest did not deprive” Diamond of
patentee status, id. at 30; “Sanyo’s non-exclusive license
did not affect” Diamond’s patentee status, id. at 31; and
“Sanyo did not control [Diamond]’s ability to enforce the
patents-in-suit,” id. at 33. Thus, Diamond contends that
the PATA transferred to it all substantial rights in the
patents-in-suit. Id. at 12.
    We need not resolve all of Diamond’s questions be-
cause two characteristics of the PATA resolve the issue
before us. We “have never . . . establish[ed] a complete


    3   In its opening brief, Diamond states that various
provisions in the PATA were intended to achieve a partic-
ular result, see, e.g., Appellant’s Br. 34, 37, but it cites no
evidence to support its statements, see id. Accordingly,
we disregard them as speculative. See Lucent Techs., Inc.
v. Gateway, Inc., 580 F.3d 1301, 1327 (Fed. Cir. 2009)
(speculation does not equate to evidence).
DIAMOND COATING TECHS., LLC   v. HYUNDAI MOTOR AM.            7



list of the rights” that “must be examined to determine
whether a [patentee] has transferred away sufficient
rights to render an[other party] . . . the owner of a pa-
tent.” Alfred E. Mann, 604 F.3d at 1360. However, we
have observed that (1) “the exclusive right to make, use,
and sell . . . is vitally important,” and (2) “the nature and
scope of the [patentee’s] retained right to sue accused
infringers [and license the patent are] the most important
factor[s] in determining whether an [agreement] . . .
transfers sufficient rights to render the [other party] the
owner of the patent.” Id. at 1360–61 (emphasis added).
We examine each of these issues in turn.
      With respect to the first, Diamond does not possess
sufficient rights to make, use, or sell the patented inven-
tion. We have held that a “licensor’s retention of a limited
right to develop and market the patented invention
indicates that the licensee failed to acquire all substantial
rights.” Fieldturf, Inc. v. Sw. Recreational Indus., Inc.,
357 F.3d 1266, 1269 (Fed. Cir. 2004) (citation omitted).
Sanyo retains a right and license to make, use, and sell
products covered by the patents-in-suit. Section 2.4(a) of
the PATA provides Sanyo with “a world-wide, royalty-
free, non-exclusive, non-sublicensable, non-transferable
. . . right and license . . . to practice the methods and to
make, have made, use, distribute, lease, sell, offer for sale,
import, export, develop and otherwise dispose of and
exploit any” products covered by the patents-in-suit,
including any “foundry[4] or contract manufacturing
activities . . . that [Sanyo] . . . currently undertake[s] . . .
or may undertake in the future.” J.A. 204. Indeed, the
PATA does not even grant Diamond a right to practice the



    4   A “foundry” right is “a licensee’s right[] to make a
product and sell it under a third party’s name.”
CoreBrace LLC v. Star Seismic LLC, 566 F.3d 1069, 1071
(Fed. Cir. 2009).
8              DIAMOND COATING TECHS., LLC   v. HYUNDAI MOTOR AM.



patents-in-suit. Section 5.1.1 of the PATA limits Diamond
to the “prosecution, maintenance, licensing, litigation,
enforcement and exploitation” of the patents-in-suit and
explains that Diamond “shall engage in no [other] busi-
ness or activity.” J.A. 208. Thus, in this respect, Dia-
mond unquestionably failed to acquire all substantial
rights in the patents-in-suit.
    Diamond contends that the court should construe “ex-
ploitation” in Section 5.1.1 of the PATA to mean “practice”
and “sell,” such that the PATA provides Diamond with
sufficient rights to make, use, and sell the patented
invention. Appellant’s Br. 24–26 (equating “exploitation”
with “selling”); Oral Argument at 35:21–35:55 (equating
“practice” with “exploitation”), available at http://oralargu
ments.cafc.uscourts.gov/default.aspx?fl=2015-1844.mp3.
“Practice” and “sell” appear in Section 2.4(a) of the PATA.
J.A. 204. If the parties intended for Diamond to possess
the rights to practice and sell the patents-in-suit, Section
2.4(a) indicates that they knew how to say so. 5 See
Dreisinger, 13 N.Y.S.3d at 435 (“Our function is to apply
the meaning intended by the parties, as derived from the
language of the contract in question.” (internal quotation
marks and citations omitted)).
     With respect to the second issue, “[r]etaining control
of [licensing or litigation] activities is [] critical to demon-


    5   Among other words, “exploitation” follows “prose-
cution,” “licensing,” “litigation,” and “enforcement” in
Section 5.1.1 of the PATA, which indicates that “exploita-
tion” concerns enforcement activities not explicitly ad-
dressed by the PATA. See J.A. 208; see also Harris v.
Allstate Ins. Co., 127 N.E.2d 816, 818 (N.Y. 1955) (apply-
ing the principle noscitur a sociis—that the meaning of a
word should be derived from the words immediately
surrounding it—to interpret a contract); Noscitur a Sociis,
Black’s Law Dictionary (10th ed. 2014).
DIAMOND COATING TECHS., LLC   v. HYUNDAI MOTOR AM.        9



strating that the patent has not been effectively assigned
to the licensee.” Azure Networks, LLC v. CSR PLC, 771
F.3d 1336, 1343 (Fed. Cir. 2014) (citations omitted),
vacated on other grounds, 135 S. Ct. 1846 (2015). Sanyo
retained significant control over Diamond’s enforcement
and litigation activities. First, the PATA conditions
Diamond’s litigation and enforcement activities on
Sanyo’s best interests. Section 5.1.4 of the PATA states
that Diamond, “in its reasonable sole discretion,” “shall
pursue the licensing, litigation, enforcement and other
exploitation of the [patents-in-suit] to generate revenue
for so long as [Diamond] determines in good faith, taking
into consideration the best interests of [Diamond] and
[Sanyo], that it is commercially reasonably to do so.” J.A.
209 (emphases added). Second, the PATA cabins Dia-
mond’s authority to license the patents-in-suit. Section
5.2.2 of the PATA explains that Diamond “shall not”
license the patents-in-suit jointly with patents owned by
another party absent Sanyo’s prior written consent. J.A.
210. Third, the PATA and Ancillary Agreement limit
Diamond’s discretion to refrain from suing certain com-
panies. As the District Court observed, the agreements
provide
    a list of companies which [Diamond] “reserves the
    right not to assert the [patents-in-suit] against.”
    Sanyo “acknowledges and agrees” that [Dia-
    mond]’s decision not to seek enforcement against
    these companies “shall not form a basis for alleg-
    ing that [Diamond] breached any obligation under
    the PATA.” Furthermore, [Diamond] may not add
    companies to [the list] “in bad faith or in a man-
    ner that would reasonably be viewed as circum-
    vention of the business objectives” of the [PATA].
Diamond, 2015 WL 2088892, at *6 (brackets and citations
omitted). The District Court properly concluded that, “if
[Diamond] had unfettered discretion on enforcement, then
[the list] would be superfluous.” Id. Section 5 and Ap-
10            DIAMOND COATING TECHS., LLC   v. HYUNDAI MOTOR AM.



pendix 2 of the Ancillary Agreement also provide a list of
“companies that Sanyo reasonably believes represent
licensing opportunities” and restrict Diamond’s ability to
remove companies from that list. J.A. 249, 256. These
provisions show that Sanyo retained significant control
over Diamond’s enforcement and litigation activities.
    The PATA and the Ancillary Agreement therefore did
not convey all of the substantial rights in the patents-in-
suit to Diamond. Accordingly, we hold that Diamond is
not a “patentee” under 35 U.S.C. § 281.
 IV. Precedent Bars Consideration of the Nunc Pro Tunc
                      Agreements
    Following the District Court’s decision in Diamond,
Diamond and Sanyo executed nunc pro tunc agreements, 6
purportedly “to clarify the parties’ original intent; namely,
to grant full ownership of the patents in question to
[Diamond].” Appellant’s Br. 12. Diamond asserts these
nunc pro tunc agreements effectively establish Diamond’s
status as a patentee. Id. at 43. We conclude they do not.
    In Alps South, LLC v. Ohio Willow Wood Co., we held
that “[n]unc pro tunc assignments are not sufficient to
confer retroactive [patentee status].” 787 F.3d 1379, 1384
(Fed. Cir. 2015) (citation omitted). Although Diamond
contends that the nunc pro tunc agreements cure its
patentee problems, Appellant’s Br. 43–49, it concedes that
“the panel should . . . affirm . . . based on Alps South”
unless there is “intervening authority from an en banc
panel of this Court or the Supreme Court,” id. at 43.
Because neither the en banc court nor the Supreme Court
has overruled Alps South, we reject Diamond’s argument.
See Deckers Corp. v. United States, 752 F.3d 949, 965


     6  The phrase “nunc pro tunc” means “[h]aving ret-
roactive legal effect.” Nunc Pro Tunc, Black’s Law Dic-
tionary (10th ed. 2014).
DIAMOND COATING TECHS., LLC   v. HYUNDAI MOTOR AM.    11



(Fed. Cir. 2014) (explaining that panels do not have the
authority to overrule prior precedential panel decisions
unless the en banc court or the Supreme Court overturns
the prior decision).
                        CONCLUSION
    We have considered Diamond’s remaining arguments
and find them unpersuasive. Accordingly, the decisions of
the United States District Court for the Central District
of California are
                        AFFIRMED
