  United States Court of Appeals
      for the Federal Circuit
                ______________________

                    XILINX, INC.,
                   Plaintiff-Appellant

                           v.

       PAPST LICENSING GMBH & CO. KG,
               Defendant-Appellee
             ______________________

                      2015-1919
                ______________________

   Appeal from the United States District Court for the
Northern District of California in No. 5:14-cv-04963-LHK,
Judge Lucy H. Koh.
                 ______________________

              Decided: February 15, 2017
               ______________________

   MATTHEW J. SILVEIRA, Jones Day, San Francisco, CA,
argued for plaintiff-appellant. Also represented by
PATRICK THOMAS MICHAEL.

    NICOLE E. GLAUSER, DiNovo, Price, Ellwanger & Har-
dy LLP, Austin, TX, argued for defendant-appellee. Also
represented by ANDREW DINOVO, JAY D. ELLWANGER.

    CHARLES DUAN, Public Knowledge, Washington, DC,
for amici curiae Public Knowledge, Electronic Frontier
Foundation. Also represented by VERA RANIERI, Electronic
Frontier Foundation, San Francisco, CA.
2              XILINX, INC.   v. PAPST LICENSING GMBH & CO. KG



    STEVEN MOORE, Kilpatrick Townsend & Stockton
LLP, San Francisco, CA, for amici curiae for AO
Kaspersky Lab, Limelight Networks, Inc., QVC, Inc., SAS
Institute Inc., Symmetry LLC, Vizio, Inc.

    HARRISON J. FRAHN, IV, Simpson Thacher & Bartlett,
LLP, Palo Alto, CA, for amici curiae Thirty-Four Law
Professors.
                ______________________

    Before PROST, Chief Judge, NEWMAN, and DYK, Circuit
                         Judges.
DYK, Circuit Judge.
    Xilinx, Inc., (“Xilinx”) appeals from a judgment of the
United States District Court for the Northern District of
California dismissing Xilinx’s declaratory judgment action
against Papst Licensing GmbH & Co. KG (“Papst”) for
lack of personal jurisdiction. Because we hold that the
district court has specific personal jurisdiction over Papst
with respect to Xilinx’s declaratory judgment action, we
reverse and remand.
                       BACKGROUND
    Xilinx is a Delaware corporation that is headquar-
tered in San Jose, California. Xilinx designs, develops,
and markets programmable logic devices for use in elec-
tronics systems. Papst is the assignee of U.S. Patent Nos.
6,574,759 and 6,704,891 (collectively, “the patents-in-
suit”), which are directed to methods for generating and
verifying memory tests in electronics.
    Papst is organized under the laws of Germany and
has its principal place of business there. Papst is a non-
practicing entity that is solely in the business of monetiz-
ing and licensing intellectual property rights. According
to Papst, it “has always been in the business of obtaining
and licensing patents, it does not manufacture or sell any
XILINX, INC.   v. PAPST LICENSING GMBH & CO. KG           3



consumer products, and it has always had fewer than 30
employees.” J.A. 1133. Xilinx points to various Papst
marketing materials and its website in which Papst
describes itself as “a global patent licensing and moneti-
zation firm specialized in enforcing infringed patents with
the goal to conclude a license agreement with the infring-
er.” Exhibit 9 at 1, Declaration of Jason M. Gonder,
Xilinx, Inc. v. Papst Licensing GmbH & Co. KG, No. 5:14-
cv-04963-LHK (N.D. Cal. Apr. 15, 2015), ECF No. 53-9
(“Exhibit 9”).
     These materials explain the business model by which
Papst acquires and then asserts patent rights. “Before
agreeing to purchase a patent,” Papst performs “due
diligence” to “identify patent infringement by comparing
the patent claims against the potentially infringing
products.” J.A. 1733. Papst’s due diligence involves
“identify[ing] the companies potentially involved in in-
fringements, and the markets they are selling their
product in—where they are located, and how large they
are, including where the product is made as well as where
it is sold.” Id.
    When Papst identifies infringers, it “notif[ies] them
that [Papst] believe[s] they are infringing.” Id. Papst
“then travel[s] extensively to visit the infringers.” Id.
“After technical discussions confirming the infringement,
the conversation moves towards licensing the patents
through an agreement.” Id. “If negotiations fail, [Papst]
is prepared to effectively enforce the respective patents in
courts. Especially in the United States, Germany, and
the Netherlands [Papst has] years and years of experience
in patent litigation.” Exhibit 9 at 1. Papst’s marketing
materials explain that Papst has “been very successful
with legal actions. With [Papst’s] outside partners includ-
ing attorneys, [Papst has] been very successful and won
many high-profile patent cases.” J.A. 1733.
4              XILINX, INC.   v. PAPST LICENSING GMBH & CO. KG



    Papst has repeatedly filed patent infringement suits
in California federal courts. The record shows that Papst
has filed patent infringement lawsuits in California at
least seven times between 1994 and 2007 based on other
patents in Papst’s portfolio.
    Papst’s actions leading up to the filing of this declara-
tory judgment action are consistent with Papst’s business
model. Before acquiring the patents-in-suit in October
2012, Papst performed its due diligence by investigating
potential infringers and targets for licensing of those
patents. Xilinx describes the investigation as involving
twenty-nine target companies, twenty-eight of which are
based, or have significant presence, in California. One of
the companies that Papst investigated was Xilinx.
    In January 2014, Papst sent a patent-infringement
notice letter to Xilinx. In the letter, Papst identified
several of Xilinx’s products that allegedly infringed the
patents-in-suit, and stated that “Papst proposes com-
mencing discussions with Xilinx so that Xilinx can consid-
er taking a license to the Papst Patents.” J.A. 1053. After
Xilinx did not respond to Papst’s first set of letters, in
April 2014, Papst sent a second letter, “again encour-
ag[ing] Xilinx to participate in a dialogue regarding
taking a license to the” patents-in-suit. J.A. 1056. On
October 16, 2014, three representatives of Papst, includ-
ing Papst’s managing director, its senior counsel, and its
Texas-based outside counsel, traveled to California to
meet with Xilinx. The purpose of the meeting was to
discuss Papst’s allegations of infringement of the patents-
in-suit and Xilinx’s potential licensing of these patents.
No agreement resulted from these contacts.
    On November 7, 2014, Xilinx filed this declaratory
judgment action in the Northern District of California
seeking a declaration that Xilinx’s products do not in-
fringe the patents-in-suit and that the patents are invalid.
On the same day that Xilinx filed its declaratory judg-
XILINX, INC.   v. PAPST LICENSING GMBH & CO. KG            5



ment action in California, Papst filed an infringement suit
against Xilinx in the District of Delaware asserting the
same patents-in-suit. Papst moved to dismiss the Cali-
fornia declaratory judgment action for lack of personal
jurisdiction, or in the alternative, transfer the action to
the District of Delaware.
    On July 9, 2015, the court granted Papst’s motion and
dismissed the declaratory judgment action for lack of
personal jurisdiction. The court first determined that it
lacked general jurisdiction over Papst because it “is not at
home in California,” recognizing that “Papst is not incor-
porated in California, nor does it have its principal place
of business” there. J.A. 8–10.
     The court also held that it lacked specific personal ju-
risdiction over Papst. The court observed that “Papst
certainly has many connections to the state of California.”
J.A. 22–23. However, relying principally on our decisions
in Red Wing Shoe Co. v. Hockerson-Halberstadt, Inc., 148
F.3d 1355 (Fed. Cir. 1998), and its progeny, the court
recognized that “even if the ‘purposefully directed’ and
‘arises out of’ prongs are satisfied by the defendant’s
enforcement activities” in the forum, “[n]ot all assertions
of jurisdiction based on enforcement activities comport
with ‘fair play and substantial justice.’” J.A. 11 (citing
Avocent Huntsville Corp. v. Aten Int’l Co., 552 F.3d 1324,
1333 (Fed. Cir. 2008)). The court determined that Papst’s
California contacts were “either related solely to Papst’s
attempts to license the patents, which the Federal Circuit
has held insufficient, or according to Federal Circuit law
are irrelevant to the parties’ instant dispute.” J.A. 23.
With respect to Papst’s prior litigation in California, the
court explained that these “enforcement activities regard-
ing other patents are irrelevant to the question at hand:
whether this Court can assert specific jurisdiction over
Papst based on its efforts to enforce the patents-in-suit.”
J.A. 22. “The Federal Circuit has ‘consistently’ made
clear that the ‘other activities’ for purposes of personal
6               XILINX, INC.   v. PAPST LICENSING GMBH & CO. KG



jurisdiction must relate to ‘the relevant patents.’” Id.
(quoting Avocent, 552 F.3d at 1334). The court concluded
that “even when considered as a whole these connections
are insufficient to vest this Court with specific jurisdiction
over Papst.” J.A. 23.
    The court declined to allow additional discovery relat-
ed to Papst’s prior enforcement activities in California.
The court noted that Papst had already provided some
discovery and concluded that additional discovery would
be a waste of resources.
   Xilinx appeals. We have jurisdiction pursuant to 28
U.S.C. § 1295(a)(1). 1
                         DISCUSSION
                       I.   MOOTNESS
    Papst first argues that events post-dating Xilinx’s fil-
ing of this appeal render the appeal moot. We disagree.
“A case becomes moot . . . ‘only when it is impossible for a
court to grant any effectual relief whatever to the prevail-
ing party.’” Campbell-Ewald Co. v. Gomez, 136 S. Ct. 663,
669 (2016), as revised (Feb. 9, 2016) (quoting Knox v. Serv.
Emps., 132 S. Ct. 2277, 2287 (2012)). Following dismissal
of Xilinx’s California declaratory judgment action in-



    1    Altera Corporation (“Altera”) was also a party to
this appeal. Like Xilinx, it filed a declaratory judgment
action in the Northern District of California, and Papst
filed an infringement suit in the District of Delaware.
The Northern District of California also dismissed Al-
tera’s declaratory judgment action for lack of personal
jurisdiction. We subsequently granted Altera’s unopposed
motion for a determination that its appeal was moot
based on Altera’s filing of declaratory judgment counter-
claims in Papst’s California patent infringement action
after it was transferred from Delaware.
XILINX, INC.   v. PAPST LICENSING GMBH & CO. KG              7



volved in this appeal, on February 23, 2016, the District of
Delaware transferred Papst’s infringement suit to the
Northern District of California—the same court that had
dismissed the declaratory judgment action. Papst argues
that the transferred action has provided Xilinx another
opportunity to bring its declaratory judgment action as a
counterclaim in its desired forum, rendering this appeal
moot.
    However, Xilinx has not asserted declaratory judg-
ment counterclaims in the transferred action. The mere
availability of this unpursued alternative route to relief
does not render moot Xilinx’s action seeking the same
relief. See Campbell-Ewald Co., 136 S. Ct. at 672 (“[A]n
unaccepted settlement offer or offer of judgment does not
moot a plaintiff’s case . . . .”). Accordingly, Xilinx’s appeal
is not moot.
                  II. PERSONAL JURISDICTION
    The central issue in this case is whether the exercise
of specific personal jurisdiction over Papst in California is
fair and reasonable. “Personal jurisdiction is a question
of law that we review de novo.” Autogenomics, Inc. v.
Oxford Gene Tech. Ltd., 566 F.3d 1012, 1016 (Fed. Cir.
2009). Because Xilinx’s declaratory judgment appeal
involves only claims of patent noninfringement, “we apply
Federal Circuit law because the jurisdictional issue is
intimately involved with the substance of the patent
laws.” Id. (internal quotation marks omitted) (quoting
Avocent, 552 F.3d at 1328). Where, as here, “the district
court’s disposition as to the personal jurisdictional ques-
tion is based on affidavits and other written materials in
the absence of an evidentiary hearing, a plaintiff need
only to make a prima facie showing that defendants are
subject to personal jurisdiction.” Avocent, 552 F.3d at
1329 (quoting Elecs. for Imaging, Inc. v. Coyle, 340 F.3d
1344, 1349 (Fed. Cir. 2003)). We, like the district court,
“accept the uncontroverted allegations in the plaintiff’s
8              XILINX, INC.   v. PAPST LICENSING GMBH & CO. KG



complaint as true and resolve any factual conflicts in the
affidavits in the plaintiff’s favor.” Id.
                               A
    “Determining whether jurisdiction exists over an out-
of-state defendant involves two inquiries: whether a
forum state’s long-arm statute permits service of process
and whether assertion of personal jurisdiction violates
due process.” Autogenomics, 566 F.3d at 1017 (quoting
Genetic Implant Sys., Inc. v. Core-Vent Corp., 123 F.3d
1455, 1458 (Fed. Cir. 1997)). California’s long-arm stat-
ute permits service of process to the full extent allowed by
the due process clauses of the United States Constitu-
tion. 2 Elecs. for Imaging, 340 F.3d at 1349; see also Cal.
Civ. Proc. Code § 410.10 (West). Accordingly, “the two
inquiries collapse into a single inquiry: whether jurisdic-
tion comports with due process.” Inamed Corp. v. Kuz-
mak, 249 F.3d 1356, 1360 (Fed. Cir. 2001).
    In the case of specific, as opposed to general jurisdic-
tion, we have summarized the Supreme Court’s due
process jurisprudence in a three-factor test: “(1) whether
the defendant ‘purposefully directed’ its activities at
residents of the forum; (2) whether the claim ‘arises out of
or relates to’ the defendant’s activities with the forum;
and (3) whether assertion of personal jurisdiction is



    2   As we explained in Akro Corp. v. Luker, 45 F.3d
1541 (Fed. Cir. 1995), the due process inquiry implicates
the Due Process Clause of the Fifth Amendment, not the
Fourteenth Amendment, because subject matter jurisdic-
tion over a patent action exists by virtue of a federal
question, not the diversity of the parties. Id. at 1544–45.
Nonetheless, we have applied the Supreme Court’s juris-
prudence of personal jurisdiction regarding the demands
of the Fourteenth Amendment’s Due Process Clause to
this context. Id.
XILINX, INC.   v. PAPST LICENSING GMBH & CO. KG            9



‘reasonable and fair.’” Inamed, 249 F.3d at 1360. “The
first two factors correspond with the ‘minimum contacts’
prong of the [International Shoe Co. v. Washington, 326
U.S. 310 (1945)] analysis, and the third factor corresponds
with the ‘fair play and substantial justice’ prong of the
analysis.” Inamed, 249 F.3d at 1360.
    With respect to the first factor of the minimum con-
tacts portion of specific personal jurisdiction analysis, “it
is essential in each case that there be some act by which
the defendant purposefully avails itself of the privilege of
conducting activities within the forum State, thus invok-
ing the benefits and protections of its laws.” Hanson v.
Denckla, 357 U.S. 235, 253 (1958). As to the second
factor, also part of the minimum contacts analysis, the
court must determine whether “the suit ‘aris[es] out of or
relate[s] to the defendant’s contacts with the forum.’”
Goodyear Dunlop Tires Operations, S.A. v. Brown, 564
U.S. 915, 923–24 (2011) (alterations in original) (quoting
Helicopteros Nacionales de Colom., S.A. v. Hall, 466 U.S.
408, 414 n.8 (1984)).
     Many of our recent cases have been concerned with
the two minimum contacts factors of the analysis. We
have considered forum-related activities of the patentee
with respect to the patents in suit that do not necessarily
relate to the particular controversy, such as exclusive
licensing, though at the same time we have (appropriate-
ly) rejected the existence of contacts concerning other
patents as being pertinent to the minimum contacts
analysis. See Avocent, 552 F.3d at 1336 (explaining
relevant contacts are those that the “defendant patentee
purposefully directs . . . at the forum which relate in some
material way to the enforcement or the defense of the
patent”); see also Campbell Pet Co. v. Miale, 542 F.3d 879,
886 (Fed. Cir. 2008) (extra-judicial patent enforcement);
Breckenridge Pharm., Inc. v. Metabolite Labs., Inc., 444
F.3d 1356, 1366 (Fed. Cir. 2006) (exclusive license); Elecs.
for Imaging, 340 F.3d at 1351 (hiring of in-forum attorney
10             XILINX, INC.   v. PAPST LICENSING GMBH & CO. KG



to communicate with plaintiff); Inamed, 249 F.3d at 1361
(exclusive license); Akro, 45 F.3d at 1548–49 (exclusive
license).
    Papst makes no argument that its activities directed
to Xilinx in California do not satisfy the minimum con-
tacts prong of the specific jurisdiction test. See Papst Br.
at 21 (“A cease-and-desist letter to a forum resident may
give rise to a declaratory judgment cause of action and
satisfy[] the minimum contacts portion of the specific
jurisdiction test.” (emphasis added)). Indeed, there is no
question that Papst has the required minimum contacts
with California. Papst purposefully directed its activities
to California when it sent multiple notice letters to Xilinx
and traveled there to discuss Xilinx’s alleged patent
infringement and potential licensing arrangements.
    Xilinx’s declaratory judgment action of noninfringe-
ment certainly relates to these contacts. In the context of
declaratory judgment actions involving assertions of
patent noninfringement or invalidity, we have concluded
that cease-and-desist letters sent by the patentee defend-
ant into the forum are relevant contacts in the personal
jurisdiction analysis. Red Wing, 148 F.3d at 1360. Mini-
mum contacts may be established by “the threat of an
infringement suit, as communicated in a cease-and-desist
letter.” Id.; see also id. (explaining that “cease-and-desist
letters alone are often substantially related to the cause of
action (thus providing minimum contacts)”).
    Even more significant than the notice letters is
Papst’s visit to Xilinx in California, another activity that
certainly “relate[s] in some material way to the enforce-
ment or the defense of the patent.” Avocent, 552 F.3d at
1336. As the Supreme Court has explained, “physical
entry into the State—either by the defendant in person or
through an agent, goods, mail, or some other means—is
certainly a relevant contact.” Walden v. Fiore, 134 S. Ct.
1115, 1122 (2014). This court has previously recognized
XILINX, INC.   v. PAPST LICENSING GMBH & CO. KG           11



that in-person visits to the forum are significant contacts
in the declaratory judgment context. See Elecs. for Imag-
ing, 340 F.3d at 1351; Deprenyl Animal Health, Inc. v.
Univ. of Toronto Innovations Found., 297 F.3d 1343, 1352
(Fed. Cir. 2002). Therefore, the minimum contacts prong
is satisfied here.
                                B
    In arguing against personal jurisdiction, Papst focus-
es entirely on the “reasonable and fair” prong and argues
that “exercising specific jurisdiction over a patentee based
solely on cease-and-desist letters, which contain notice of
the sender’s patent rights, accusations of infringement,
and/or licensing offers, does not comport with fair play or
substantial justice.” Papst Br. at 21–22 (citing Red Wing,
148 F.3d at 1360–61).
    As the Supreme Court has made clear, the specific ju-
risdiction analysis is a two-step process, and the reasona-
bleness prong is separate from the minimum contacts
prong. The Court noted in Daimler AG v. Bauman, 134 S.
Ct. 746, 762 n.20 (2014), “[f]irst, a court is to determine
whether the connection between the forum and the epi-
sode-in-suit could justify the exercise of specific jurisdic-
tion. Then, in a second step, the court is to consider
several additional factors to assess the reasonableness of
entertaining the case.” See also id. at 764 (Sotomayor, J.,
concurring) (“Our personal jurisdiction precedents call for
a two-part analysis. The contacts prong asks whether the
defendant has sufficient contacts with the forum State to
support personal jurisdiction; the reasonableness prong
asks whether the exercise of jurisdiction would be unrea-
sonable under the circumstances.”); 4 Charles Alan
Wright, Arthur R. Miller & Adam N. Steinman, Federal
Practice and Procedure § 1067.2 (4th ed. 2015) (explaining
that the Supreme Court “case law reflects a two-step
approach that requires both (1) that the defendant estab-
lish minimum contacts with the forum State, and (2) that
12             XILINX, INC.   v. PAPST LICENSING GMBH & CO. KG



the assertion of personal jurisdiction is reasonable and
comports with fair play and substantial justice”).
    The inquiry under the reasonableness prong (step
two) is not limited to the specific facts giving rise to, or
relating to, the particular litigation. “Once it has been
decided that a defendant purposefully established mini-
mum contacts within the forum State, these contacts may
be considered in light of other factors to determine wheth-
er the assertion of personal jurisdiction would comport
with ‘fair play and substantial justice.’” Burger King
Corp. v. Rudzewicz, 471 U.S. 462, 476 (1985) (emphasis
added) (quoting Int’l Shoe, 326 U.S. at 320). These other
factors—the burden on the defendant, the plaintiff’s
interest in obtaining convenient and effective relief, etc.,
id. at 477—often cannot be analyzed without looking to
circumstances beyond those that give rise or relate to the
specific lawsuit.
    In Asahi Metal Industry Co. v. Superior Court of Cal.,
Solano Cty., 480 U.S. 102, 116 (1987), the one case where
the Supreme Court held that the reasonableness re-
quirement was not satisfied, the Court looked beyond
minimum contacts to consider other factors. For instance,
the Court explained that the distance between Asahi’s
headquarters in Japan and the California forum, as well
as subjecting a foreign company to United States law,
would impose a heavy burden on Asahi. Id. at 114. The
Court also explained that the plaintiff, another foreign
entity, did not demonstrate that litigating in California
would be more convenient than litigating in Taiwan or
Japan. Id.
    While the reasonableness inquiry is not limited to
considering the minimum contacts, the Supreme Court
has made clear that the reasonableness prong is typically
satisfied by a showing of minimum contacts. “Where a
defendant who purposefully has directed his activities at
forum residents seeks to defeat jurisdiction, he must
XILINX, INC.   v. PAPST LICENSING GMBH & CO. KG            13



present a compelling case that the presence of some other
considerations would render jurisdiction unreasonable.”
Burger King, 471 U.S. at 477; see also id. at 476 (explain-
ing that where a defendant’s “activities are shielded by
the benefits and protections of the forum’s laws it is
presumptively not unreasonable to require him to submit
to the burdens of litigation in that forum as well” (quota-
tion marks omitted)). The Court identified five considera-
tions relevant to the reasonableness analysis:
    [C]ourts in “appropriate case[s]” may evaluate [1]
    “the burden on the defendant,” [2] “the forum
    State’s interest in adjudicating the dispute,” [3]
    “the plaintiff’s interest in obtaining convenient
    and effective relief,” [4] “the interstate judicial
    system’s interest in obtaining the most efficient
    resolution of controversies,” and [5] the “shared
    interest of the several States in furthering fun-
    damental substantive social policies.”
Id. at 477 (second alteration in original) (quoting World-
Wide Volkswagen, 444 U.S. at 292).
     Here, as discussed in Part II.A above, Papst has the
required minimum contacts with California to make the
exercise of personal jurisdiction presumptively reasona-
ble. For the reasons that follow, Papst has failed to meet
its burden to show a “compelling case” under Burger King
that jurisdiction is unreasonable. 471 U.S. at 477.
    Papst makes no argument that factors 2–5 weigh
against a finding of personal jurisdiction, see id., nor could
it. Xilinx, which is headquartered in California, indisput-
ably has an interest in protecting itself from patent
infringement by obtaining relief “from a nearby federal
court” in its home forum. 3 Breckenridge, 444 F.3d at


    3 Absent an ability to litigate its declaratory judg-
ment action in California, Xilinx would be remitted to
14             XILINX, INC.   v. PAPST LICENSING GMBH & CO. KG



1367–68 (explaining that one reasonableness factor
“requires the court to focus on the convenience and effec-
tiveness of relief from the plaintiff’s perspective”). The
Supreme Court has recognized the importance of declara-
tory judgment actions in patent cases for allowing accused
infringers to secure a determination that their products
do not infringe the patent or that the patent is invalid.
See Medtronic, Inc. v. Mirowski Family Ventures, LLC,
134 S. Ct. 843, 849 (2014); MedImmune, Inc. v. Genentech,
Inc., 549 U.S. 118, 137 (2007). Likewise, California has
“definite and well-defined interests in commerce and
scientific development,” Viam Corp. v. Iowa Exp.-Imp.
Trading Co., 84 F.3d 424, 430 (Fed. Cir. 1996), and “Cali-
fornia has a substantial interest in protecting its resi-
dents from unwarranted claims of patent infringement,”
Elecs. for Imaging, 340 F.3d at 1352. Jurisdiction over
Xilinx’s declaratory judgment claims in California would
also result in an efficient resolution of the controversy.
Finally, there does not appear to be any conflict between
the interests of California and any other state, because
“the same body of federal patent law would govern the
patent invalidity claim irrespective of the forum.” Id.
    This leaves for our consideration the burden on the
defendant. With respect to this factor, the Supreme Court
has explained, “[w]hen minimum contacts have been
established, often the interests of the plaintiff and the
forum in the exercise of jurisdiction will justify even the
serious burdens placed on the alien defendant.” Asahi,
480 U.S. at 114. Thus, instances in which the fairness
analysis will defeat “otherwise constitutional personal
jurisdiction are limited to the rare situation in which the



litigating on the opposite side of the country in the United
States District Court for the Eastern District of Virginia,
the statutory venue for actions against patentees not
residing in the United States. See 35 U.S.C. § 293.
XILINX, INC.   v. PAPST LICENSING GMBH & CO. KG             15



plaintiff’s interest and the state’s interest in adjudicating
the dispute in the forum are so attenuated that they are
clearly outweighed by the burden of subjecting the de-
fendant to litigation within the forum.” Akro, 45 F.3d at
1549 (quotation marks omitted).
    Papst argues that its contacts with Xilinx in Califor-
nia are insufficient to justify the burden of litigating in
that forum. Papst focuses on our prior cases holding that
because of “policy considerations unique to the patent
context,” Silent Drive, Inc. v. Strong Indus., Inc., 326 F.3d
1194, 1206 (Fed. Cir. 2003), a patentee’s sending of warn-
ing letters and offers to license, “without more, . . . are not
sufficient to satisfy the requirements of Due Process in
declaratory judgment actions.” Red Wing, 148 F.3d at
1360.
    In Red Wing, we explained that although warning let-
ters satisfy the requirement of minimum contacts, “such
letters cannot satisfy the [fairness] prong of the Due
Process inquiry.” Id. at 1361. We explained the rationale
for this rule: “[p]rinciples of fair play and substantial
justice afford a patentee sufficient latitude to inform
others of its patent rights without subjecting itself to
jurisdiction in a foreign forum.” Id. at 1360–61. To
require a defendant to answer “in a distant foreign forum
when its only contacts with that forum were efforts to give
proper notice of its patent rights” would place an undue
burden on the defendant. 4 Id. at 1361.



    4    The court further held that the inclusion of offers
to license the patents “within a cease-and-desist letter
does not somehow convert that letter into something more
than it was already.” Id. The court explained that “[a]n
offer to license is more closely akin to an offer for settle-
ment of a disputed claim rather than an arms-length
negotiation in anticipation of a long-term continuing
16              XILINX, INC.   v. PAPST LICENSING GMBH & CO. KG



    We disagree with Papst that this case is controlled by
Red Wing and its holding that certain types of contacts,
by themselves, are not sufficient to establish the reasona-
bleness of jurisdiction. As we have discussed in the
minimum contacts analysis, Papst has done more than
just send letters to Xilinx. Representatives from Papst
traveled to California to meet with Xilinx in person to
discuss Papst’s infringement contentions and licensing
offer with respect to the patents-in-suit. 5 The Supreme
Court noted in Burger King that “territorial presence
frequently will enhance a potential defendant’s affiliation
with a State and reinforce the reasonable foreseeability of
suit there.” 471 U.S. at 476.
     Moreover, there are other facts that, under the Burger
King analysis, confirm the view that the burden on the
defendant is not undue. For instance, the burden on
Papst is mitigated by Papst’s status as a non-practicing
patent holder residing outside the United States. This is
not a case like Red Wing, where the defendant conducts
its affairs in one state and is called to litigate in a distant
state rather than its own residence. See 148 F.3d at 1357.
By the very nature of its business, Papst must litigate its
patents in the United States in fora far from its home




business relationship” and that the policy favoring set-
tlement “squarely invokes one of the considerations
enumerated by the Supreme Court for the second prong of
a proper Due Process analysis, namely, ‘the interstate
judicial system’s interest in obtaining the most efficient
resolution of controversies.’” Id. (quoting World-Wide
Volkswagen Corp. v. Woodson, 444 U.S. 286, 292 (1980)).
    5   We note that Papst also traveled twice to Califor-
nia to meet with Altera for the same purpose.
XILINX, INC.   v. PAPST LICENSING GMBH & CO. KG        17



office. In this context the burden on Papst to litigate in
California appears not undue. 6
     The lack of significant burden on Papst is also evi-
denced by Papst’s prior litigations in California itself.
Papst has repeatedly availed itself of the California
federal court system—at least seven times—by filing
patent infringement lawsuits there. In this respect, this
case is similar to Viam. In Viam, we held that requiring
an Italian patent owner and its Iowa exclusive agent to
litigate a declaratory judgment action in California was
not unduly burdensome where those entities had initiated
a suit enforcing the same patent in the same district in
California against other parties. 84 F.3d at 430. Our
reasoning that personal jurisdiction was fair rested in
relevant part on the fact that the suit demonstrated that
the patent owner “has found a way to shoulder successful-
ly the burden of litigating in California.” Id.
    Our decision in Acorda Therapeutics Inc. v. Mylan
Pharmaceuticals Inc., 817 F.3d 755, 764 (Fed. Cir. 2016),
makes clear the relevance of a defendant’s litigations in
the forum. There we explained that the burden on an
accused infringer answering an infringement lawsuit “will
be at most modest, as [the accused infringer], a large
generic manufacturer, has litigated many . . . lawsuits in
[the forum], including some that it initiated.” Id.
    Finally, Papst has not made any demonstration that
it would be unduly burdensome to litigate in California.
For all of these reasons, therefore, we hold that Papst




    6   We do not suggest that the foreign location of a
defendant itself supports personal jurisdiction. See Avo-
cent, 552 F.3d at 1339. Rather, we note that Papst, as a
non-practicing patent owner, necessarily must litigate its
patents somewhere in the United States.
18              XILINX, INC.   v. PAPST LICENSING GMBH & CO. KG



would not be subject to undue burdens if forced to defend
its patents in California.
    In light of the totality of circumstances present in this
case, this is not “one of the ‘rare’ situations in which
sufficient minimum contacts exist but where the exercise
of jurisdiction would be unreasonable.” Elecs. for Imag-
ing, 340 F.3d at 1352. In other words, there is simply no
“compelling case” here that personal jurisdiction over
Papst is unreasonable. Burger King, 471 U.S. at 477.
                        CONCLUSION
    We hold that Xilinx has established that personal ju-
risdiction over Papst is proper in California. We need not
address Xilinx’s additional arguments regarding the
district court’s denial of jurisdictional discovery. Accord-
ingly, we reverse the district court’s dismissal of Xilinx’s
declaratory judgment complaint with respect to its nonin-
fringement claims and remand for further proceedings
consistent with this opinion.
             REVERSED AND REMANDED
                               COSTS
     Costs to Xilinx.
