  United States Court of Appeals
      for the Federal Circuit
               ______________________

                 ENOCEAN GMBH,
                    Appellant,

                          v.

     FACE INTERNATIONAL CORPORATION,
                    Appellee.
             ______________________

                     2012-1645
               ______________________

    Appeal from the United States Patent and Trademark
Office, Board of Patent Appeals and Interferences, in
Interference No. 105,755.
                 ______________________

              Decided: January 31, 2014
               ______________________

    GEORGE E. QUILLIN, Foley & Lardner LLP, of Wash-
ington, DC, argued for appellant.

    DUNCAN G. BYERS, Byers Law Group, of Norfolk, Vir-
ginia, argued for appellee.
                  ______________________

 Before RADER, Chief Judge, LOURIE and PROST, Circuit
                       Judges.
2               ENOCEAN GMBH   v. FACE INTERNATIONAL CORP



PROST, Circuit Judge.
    EnOcean GmbH (“EnOcean”) appeals from an order of
the U.S. Patent and Trademark Office (“PTO”), Board of
Patent Appeals and Interferences (“Board”), finding all of
EnOcean’s claims involved in Patent Interference No.
105,755 with Face International Corporation (“Face”)
unpatentable over a combination of prior art that includes
PCT Application No. PCT/GB01/00901 to Burrow (“Bur-
row reference”). See J.A. 50. Because the Board erred in
treating certain EnOcean claims as means-plus-function
claims and in finding that certain EnOcean claim limita-
tions lack support in its priority German and PCT appli-
cations, we vacate-in-part 1 the Board’s order with respect
to EnOcean’s claims and motions, and we remand for
further proceedings.
                     I. BACKGROUND
    EnOcean owns the rights to U.S. Patent Application
No. 10/304,121 (“EnOcean application”), which contains
claims to a self-powered switch. The switch can be used
to turn on and off lights, appliances, and other devices
without a battery or a connection to an electrical outlet.
    The named inventors on the EnOcean Application
originally filed a patent application disclosing their new
switch in Germany on May 24, 2000 (DE 10025 561.2),
and on May 21, 2001 they filed a PCT application with a
similar disclosure.        See PCT Application No.
PCT/DE01/01965.
    Following EnOcean’s formal suggestion, the Board de-
clared an interference on June 25, 2010 between EnOcean



    1   Since Face has not appealed the Board’s finding
that all of its claims involved in the interference are
unpatentable as obvious, the portion of the Board’s opin-
ion that relates to Face’s claims remains intact.
ENOCEAN GMBH   v. FACE INTERNATIONAL CORP                3



and Face, the real party of interest in U.S. Patent No.
7,084,529, which also claims a self-powered switch.
Subsequently, the Board found that all the involved Face
claims were unpatentable under 35 U.S.C. § 103 in view
of the Burrow reference in combination with several other
references. J.A. 41. Face has not appealed this determi-
nation.
    Under 37 C.F.R. § 41.207(c), 2 the Board next applied a
presumption that EnOcean’s claims would be unpatenta-
ble for the same reasons that Face’s claims were un-
patentable.    J.A. 45.   EnOcean’s sole argument for
rebutting the presumption required a determination that
EnOcean’s involved claims could benefit from the filing
date of its German and PCT applications, thereby elimi-
nating the Burrow reference from the realm of prior art. 3
However, the Board found that EnOcean’s disclosure of a
“receiver” in its German application did not support the



   2    Section 41.207(c) states: “When a motion for
judgment of unpatentability against an opponent’s claim
on the basis of prior art is granted, each of the movant’s
claims corresponding to the same count as the opponent’s
claim will be presumed to be unpatentable in view of the
same prior art unless the movant in its motion rebuts this
presumption.”
    3   The Burrow reference is a published PCT applica-
tion with a publication date of September 13, 2001 and an
international filing date of March 5, 2001. Since the
Burrow reference was filed on or after November 29,
2000, designated the United States, and was published in
English, it is available as prior art as of its PCT filing
date. 35 U.S.C. § 102(e)(2) (2002). The Burrow reference
is an intervening reference because its filing date of
March 5, 2001 falls between the U.S. filing date of the
EnOcean Application (November 25, 2002) and the filing
date of the German application (May 24, 2000).
4                ENOCEAN GMBH   v. FACE INTERNATIONAL CORP



“means for receiving” limitation in the EnOcean applica-
tion’s claims 37, 38, and 43-45 (“means-plus-function
claims”). J.A. 46-47. The Board also found that the
EnOcean application’s claims 29, 30, 32, 33, 39, 40, and 41
(“receiver claims”) were means-plus-function claims,
despite the fact that they all lack “means for” language.
J.A. 43-46. The Board explained that the word “receiver”
is defined in the claims solely in terms of functional
language, thus creating no difference between a “receiver”
and “signal receiving means.” J.A. 43-44. Therefore, the
Board accorded no benefit of priority to the receiver
claims as well, and it found all of EnOcean’s claims un-
patentable under § 103 for the same reasons that Face’s
claims were unpatentable. J.A. 45. The Board then
dismissed all other pending motions of both parties as
moot. J.A. 6-7. EnOcean timely appealed. We have
jurisdiction under 28 U.S.C. § 1295(a)(4).
                      II. DISCUSSION
     This appeal concerns two sets of EnOcean’s claims,
the receiver claims and the means-plus-function claims,
and presents two main issues: (1) whether the Board
erred in finding that the receiver claims invoke § 112, ¶ 6;
and (2) whether the Board erred in finding that both sets
of claims are not entitled to claim priority to the German
and PCT applications. We address each issue in turn.
    A. Whether the Receiver Claims Invoke § 112, ¶ 6
    It is well established that the use of the term “means”
triggers a rebuttable presumption that § 112, ¶ 6 governs
the construction of the claim term. Inventio AG v.
ThyssenKrupp Elevator Ams. Corp., 649 F.3d 1350, 1356
(Fed. Cir. 2011) (citing TriMed, Inc. v. Stryker Corp., 514
F.3d 1256, 1259 (Fed. Cir. 2008)). Conversely, where, as
here, the claim language does not recite the term
“means,” we presume that the limitation does not invoke
§ 112, ¶ 6. Id. (citing Personalized Media Commc’ns, LLC
v. Int’l Trade Comm’n, 161 F.3d 696, 703-04 (Fed. Cir.
ENOCEAN GMBH    v. FACE INTERNATIONAL CORP                   5



1998)). However, this presumption can be overcome if the
challenger demonstrates that “the claim term fails to
‘recite sufficiently definite structure’ or else recites ‘func-
tion without reciting sufficient structure for performing
that function.’” Id. (citing CCS Fitness v. Brunswick
Corp., 288 F.3d 1359, 1369 (Fed. Cir. 2002)). The correct
inquiry is “whether skilled artisans, after reading the
patent, would conclude that a claim limitation is so devoid
of structure that the drafter constructively engaged in
means-plus-function claiming.” Inventio, 649 F.3d at
1357. Therefore, “[u]ltimately, whether claim language
invokes § 112, ¶ 6 depends on how those skilled in the art
would understand the structural significance of that claim
language.” Id. at 1360.
    Whether a claim limitation invokes means-plus-
function claiming under 35 U.S.C. § 112, ¶ 6 (now 35
U.S.C. § 112(f)), is an exercise in claim construction which
we review without deference. Power Integrations, Inc. v.
Fairchild Semiconductor Int’l, Inc., 711 F.3d 1348, 1355
(Fed. Cir. 2013) (citing Inventio, 649 F.3d at 1356). 4 We
set aside factual findings of the Board “that are unsup-
ported by substantial evidence.” Falkner v. Inglis, 448
F.3d 1357, 1363 (Fed. Cir. 2006).
    Here, EnOcean challenges the Board’s construction
that its receiver claims invoke § 112, ¶ 6. The receiver
claims include the following limitations:




    4   Face argues that the Board’s construction is enti-
tled to deference if the PTO’s interpretation is reasonable
in light of all the evidence before the Board. See In re
Suitco Surface, Inc., 603 F.3d 1255, 1259 (Fed. Cir. 2010).
Although we apply de novo review to the Board’s claim
construction, in this case a more deferential standard of
review would not change the outcome.
6                ENOCEAN GMBH   v. FACE INTERNATIONAL CORP



    Claim 37: “a signal receiver for receiving a first
    electromagnetic signal transmitted by said first
    signal transmitter;”
    Claim 38: “a receiver for receiving a first radiofre-
    quency signal transmitted by said first signal
    transmitter;”
    Claim 43: “a receiver adapted to receiving a radiof-
    requency telegram transmitted by said radio fre-
    quency transmission stage;”
    Claim 45: “a receiver adapted to receiving a radiof-
    requency telegram transmitted by said first radio
    frequency transmission stage;”
EnOcean application, claims 37, 38, 43, and 45 (emphases
added). Notably, these claims all lack the word “means,”
thus entitling them to a presumption that they are not
means-plus-function claims. Despite the benefit of this
presumption, the Board concluded that “the recited ‘re-
ceiver’ element of the involved EnOcean claims invokes
§ 112, ¶ 6.” J.A. 47. The Board found “that there is no
distinction in meaning between ‘receiver’ and ‘signal
receiving means,’” and stated that “the receiver of the
EnOcean claims is defined in the claims solely in terms of
functional language.” Id.
    On appeal, EnOcean challenges the Board’s determi-
nation that its receiver claims invoke § 112, ¶6. EnOcean
argues that the claim limitation “receiver” is reasonably
well understood in the art as a name for a structure which
performs the recited function. See Greenberg v. Ethicon
Endo-Surgery, Inc., 91 F.3d 1580, 1583 (Fed. Cir. 1996)
(applying this test to the claim term “detent mechanism”).
EnOcean points to external evidence and expert testimo-
ny to support this assertion.
     Face responds by arguing that the claimed “receiver”
is defined only in terms of the function that it performs
(i.e., receiving), not its structure. Citing Blackboard, Inc.
ENOCEAN GMBH   v. FACE INTERNATIONAL CORP                  7



v. Desire2Learn, Inc., it argues that a receiver is “essen-
tially a black box that performs a recited function,” be-
cause “how it does so is left undisclosed.” 574 F.3d 1371,
1383 (Fed. Cir. 2009).
    We agree with EnOcean. The term “receiver” (i.e., the
absence of the term means) presumptively connotes
sufficiently definite structure to those of skill in the art.
See Personalized Media, 161 F.3d at 703-04. And in this
case, Face has not overcome that presumption. Indeed,
the record indicates that the term “receiver” conveys
structure to one of skill in the art—the Board itself made
a factual finding that that the “skilled worker would have
been familiar with the design and principles of the types
of components utilized in the claimed invention, includ-
ing . . . receivers.” J.A. 18.
     We also come to this conclusion, in part, because
EnOcean has provided extensive evidence demonstrating
that the term “receiver” conveys known structure to the
skilled person. See, e.g., J.A. 1772-73, 1947 (scientific
literature demonstrating that the term “receiver” was
well understood in the art); J.A. 1199-1220, 1377-87,
1434-35, 1654-64 (expert declarations addressing how
well known the term “receiver” was); see also Inventio, 649
F.3d at 1356 (calling for courts to consider relevant ex-
trinsic evidence to determine whether a claim term in-
vokes § 112, ¶ 6). Further, we are not persuaded by
Face’s arguments that the term “receiver” is simply too
broad to recite sufficiently definite structure. We have
stated previously that just because “the disputed term is
not limited to a single structure does not disqualify it as a
corresponding structure, as long as the class of structures
is identifiable by a person of ordinary skill in the art.
Linear Tech. Corp. v. Impala Linear Corp., 379 F.3d 1311,
1322 (Fed. Cir. 2004); see also Power Integrations, 711
F.3d at 1365 (“[W]e require only that the claim term be
used in common parlance or by ordinarily skilled artisans
to designate sufficiently definite structure, even if the
8                ENOCEAN GMBH     v. FACE INTERNATIONAL CORP



term covers a broad class of structures.”) (internal citation
omitted). Given the demonstrated familiarity that one of
skill in the art would have with a “receiver” and the
Board’s own factual finding that a skilled worker would
know what a “receiver” is, we hold that in this case the
term is not the “black box that performs a recited func-
tion” that Face would have us believe it is.
     This conclusion is also well supported by our prece-
dent. We have found sufficient structure in claim terms
to avoid invoking § 112, ¶ 6 in several similar cases. See,
e.g., Flo Healthcare Solutions, LLC v. Kappos, 697 F.3d
1367, 1374-75 (Fed. Cir. 2012) (holding that “height
adjustment mechanism” imparts sufficient structure so
that the presumption against applying § 112, ¶ 6 is not
overcome); Inventio, 649 F.3d at 1353, 1359-60 (holding
that “computing unit . . . for . . . evaluating . . .” is not a
means-plus-function limitation because the term connotes
a computer or other data processing device); Linear Tech.,
379 F.3d at 1320-21 (holding that term “circuit” itself in
claim term “‘circuit’ for ‘monitoring a signal from the
output terminal to generate a first feedback signal’”
connotes structure); Personalized Media Commc’ns, 161
F.3d at 704 (holding that claim term “digital detector”
recited sufficient structure to avoid § 112, ¶ 6); Greenberg,
91 F.3d at 1583-84 (holding that § 112, ¶ 6 did not apply
to the term “detent mechanism,” because “the noun ‘de-
tent’ denotes a type of device with a generally understood
meaning in the mechanical arts, even though the defini-
tions are expressed in functional terms.”). For the forego-
ing reasons, we conclude that the Board erred in finding
that the EnOcean application’s receiver claims invoked
§ 112, ¶ 6.
    B. Whether the Board Erred in Determining Priority
    Turning to the priority issue, we now examine wheth-
er the means-plus-functions claims and/or the receiver
claims are entitled to claim the benefits of the earlier
ENOCEAN GMBH   v. FACE INTERNATIONAL CORP                   9



German and PCT applications’ priority dates. This in-
quiry is crucial because, as the Board correctly noted, to
overcome the date of the Burrow reference, EnOcean
must establish that its claims are entitled to an earlier
priority date. J.A. 43.
    “To obtain the benefit of the filing date of a parent ap-
plication, the claims of the later-filed application must be
supported by the written description in the parent ‘in
sufficient detail that one skilled in the art can clearly
conclude that the inventor invented the claimed invention
as of the filing date sought.’” Anascape, Ltd. v. Nintendo
of Am. Inc., 601 F.3d 1333, 1335 (Fed. Cir. 2010) (citing
Lockwood v. Am. Airlines, Inc., 107 F.3d 1565, 1572 (Fed.
Cir. 1997)). We review de novo the Board’s legal conclu-
sions regarding priority. Eaton v. Evans, 204 F.3d 1094,
1097 (Fed. Cir. 2000).
    The Board first found, and EnOcean does not dispute,
that claims 29, 30, 32, 33, 39, and 41 are means-plus-
function claims. J.A. 44. A portion of EnOcean’s exem-
plary claim 29 is reproduced below:
    29. A switching system comprising:
    ...
    signal reception means for receiving a first elec-
    tromagnetic signal transmitted by said first signal
    transmission means;
    said signal reception means being adapted to gen-
    erate a second signal in response to said first elec-
    tromagnetic signal transmission means; . . . .
EnOcean application, claim 29 (emphases added). The
Board then looked to the German application and found
that it “makes only passing reference to the signal recep-
tion means.” J.A. 45. The German application’s only
reference to a receiver states:
10                ENOCEAN GMBH   v. FACE INTERNATIONAL CORP



     In this case, a typical scenario is that all the
     switches, for example light switches, upon actua-
     tion, emit one or a plurality of radio frequency tel-
     egrams which are received by a single receiver and
     the latter initiates the corresponding actions
     (lamp on/off, dimming of lamp, etc.).
J.A. 1276 (emphasis added). Based on that disclosure, the
Board found that “the PCT and German applications [do
not] describe the structure, materials, acts or the equiva-
lents corresponding to the claimed signal reception
means.” J.A. 46. In making its finding, the Board re-
quired that the priority documents “expressly describe the
structure of the receiver.” J.A. 45.
     Merely because we concluded above that the term “re-
ceiver” in EnOcean’s receiver claims connotes enough
structure to avoid invoking § 112, ¶ 6 does not necessarily
mean that we must conclude that the disclosure of “a
single receiver” connotes enough structure to support
EnOcean’s means-for-receiving claims for purposes of
claiming priority. Compare Inventio, 649 F.3d at 1360
(“Ultimately, whether claim language [lacking ‘means
for’] invokes § 112, ¶ 6 depends on how those skilled in
the art would understand the structural significance of
that claim language.”), with Lucent Techs., Inc. v. Gate-
way, Inc., 543 F.3d 710, 719 (Fed. Cir. 2008) (citing Bio-
medino, LLC v. Waters Techs. Corp., 490 F.3d 946, 952
(Fed. Cir. 2007)) (stating that for purposes of claiming
priority to an earlier application, “[t]he understanding of
one of skill in the art does not relieve the patentee of the
duty to disclose sufficient structure to support means-
plus-function claim terms”).
    Nonetheless, we do come to that conclusion. “Suffi-
cient structure must simply ‘permit one of ordinary skill
in the art to know and understand what structure corre-
sponds to the means limitation’ so that he may ‘perceive
the bounds of the invention.’” In re Aoyama, 656 F.3d
ENOCEAN GMBH   v. FACE INTERNATIONAL CORP                11



1293, 1298 (Fed. Cir. 2011). For the reasons articulated
in section II.A, supra, EnOcean has demonstrated that a
person of ordinary skill in the art could understand the
bounds of the invention merely by reading the term
“receiver,” which is present in EnOcean’s German and
PCT applications. In requiring that the German and PCT
applications “expressly describe the structure of the
receiver,” the Board applied an incorrect standard. J.A.
45. Since the inventors did not invent the receiver, and
the Board found that the structure was well known as of
the filing date, the inventors were “not obliged . . . to
describe . . . the particular appendage to which the im-
provement refers, nor its mode of connection with the
principal machine.” Webster Loom Co. v. Higgens, 105
U.S. 580, 586 (1881). “This enables patents to remain
concise statements of what is new, not cumbersome
repetitions of what is already known and readily provided
by reference.” Pressure Prods. Med. Supplies, Inc. v.
Greatbatch Ltd., 599 F.3d 1308, 1324 (Fed. Cir. 2010).
Thus, we conclude that the Board erred in finding on this
basis that the EnOcean application’s means-plus-function
claims were not entitled to claim the benefit of the Ger-
man and PCT applications’ priority dates.
    The Board stated that it applied the same priority
analysis to EnOcean’s receiver claims as it applied to
EnOcean’s means-plus-function claims and subsequently
concluded that the receiver claims were also not entitled
to the benefit of the German and PCT applications’ priori-
ty dates. J.A. 44. Therefore, we also conclude that the
Board erred in finding that the receiver claims were not
entitled to claim the benefit of the German and PCT
applications’ priority dates.
                     III. CONCLUSION
    For the foregoing reasons, we hold: (1) that the receiv-
er claims in EnOcean’s application do not invoke § 112,
¶ 6; (2) that the “means for receiving” limitations found in
12              ENOCEAN GMBH   v. FACE INTERNATIONAL CORP



EnOcean’s means-plus-function claims are adequately
supported by the written descriptions found in the Ger-
man and PCT applications for purposes of claiming priori-
ty; and (3) that the “receiver” limitations found in
EnOcean’s receiver claims are adequately supported by
the written descriptions found in the German and PCT
applications for purposes of claiming priority. We there-
fore vacate-in-part the Board opinion to the extent it
relates to EnOcean’s receiver and means-plus-function
claims.    We also vacate the Board’s dismissal of
EnOcean’s remaining motions and remand with instruc-
tions to the Board to consider all outstanding EnOcean
motions in view of this opinion.
       VACATED-IN-PART AND REMANDED
