  United States Court of Appeals
      for the Federal Circuit
                ______________________

              APATOR MIITORS APS,
                   Appellant

                          v.

                  KAMSTRUP A/S,
                       Appellee
                ______________________

                      2017-1681
                ______________________

    Appeal from the United States Patent and Trademark
Office, Patent Trial and Appeal Board in No. IPR2015-
01403.
                 ______________________

                Decided: April 17, 2018
                ______________________

    RICHARD JOSEPH BASILE, St. Onge Steward Johnston
& Reens, LLC, Stamford, CT, argued for appellant. Also
represented by TODD M. OBERDICK.

   MARK JOHNSON, Renner Otto, Cleveland, OH, for
appellee. Also represented by KYLE BRADFORD FLEMING.
                 ______________________

      Before MOORE, LINN, and CHEN, Circuit Judges.
MOORE, Circuit Judge.
2                        APATOR MIITORS APS   v. KAMSTRUP A/S



     Apator Miitors ApS (“Apator”) appeals from a Final
Written Decision of the United States Patent and Trade-
mark Office Patent Trial and Appeal Board (“Board”) in
an inter partes review of U.S. Patent No. 8,893,559 find-
ing claim 2 was anticipated by Nielsen, U.S. Patent App.
Pub. No. 2012/0006127, and claim 10 would have been
obvious in light of Nielsen and Körner, European Patent
App. No. 1798528. The primary issue on appeal is wheth-
er Apator can swear behind Nielsen by showing concep-
tion and reduction to practice prior to Nielsen’s effective
filing date. Because substantial evidence supports the
Board’s finding that Apator failed to sufficiently corrobo-
rate inventor Jens Drachmann’s testimony of conception,
we affirm.
                       BACKGROUND
     On June 12, 2015, Kamstrup A/S (“Kamstrup”) filed a
petition for inter partes review of the ’559 patent, and the
Board instituted review of, among other things, claims 2
and 10 based in part on Nielsen. During trial, Apator
attempted to swear behind Nielsen’s effective filing date
of March 25, 2010, a mere eighteen days before its own
effective filing date of April 12, 2010. In support, Apator
proffered a declaration from Mr. Drachmann (“Drach-
mann Declaration”) in which Mr. Drachmann declares he
conceived of his invention, an ultrasonic consumption
meter, prior to Nielsen’s effective filing date. Apator
further proffered: an email from Mr. Drachmann to Svein
Tunheim dated February 15, 2010 (“first Tunheim email”)
that the Drachmann Declaration states attached an
image file titled “mechanics6.png” (“mechanics6 file”); an
email from Mr. Drachmann to Mr. Tunheim dated
March 22, 2010 (“second Tunheim email”) that the
Drachmann Declaration states attached a presentation
titled “UFM++ venture.pdf” (“UFM++ venture file”); an
email from Mr. Drachmann to Rasmus Bjerngaard dated
March 22, 2010 (“Bjerngaard email”) that the Drachmann
Declaration states attached the UFM++ venture file; and
APATOR MIITORS APS   v. KAMSTRUP A/S                     3



a number of drawings that the Drachmann Declaration
states were created between February 15, 2010, and
March 22, 2010.
    The Board rejected Apator’s attempt to swear behind
Nielsen, determining in its Final Written Decision that
claim 2 was anticipated by Nielsen and claim 10 was
obvious based in part on Nielsen. J.A. 17-18. The Board
found that, “other than Mr. Drachmann’s own testimony,
[Apator] has presented no evidence that Mr. Drachmann
conceived the [meter] prior to the effective filing date of
Nielsen.” J.A. 16. Since “mere unsupported evidence of
the alleged inventor, on an issue of priority, as to . . .
conception and the time thereof, can not be received as
sufficient proof of . . . prior conception,” the Board rea-
soned, even “accepting as true every statement in
Mr. Drachmann’s Declaration, . . . [Apator] has failed to
produce sufficient evidence” to swear behind Nielsen. J.A.
16 (quoting Price v. Symsek, 988 F.2d 1187, 1194–95 (Fed.
Cir. 1993)). Apator appeals. We have jurisdiction under
28 U.S.C § 1295(a)(4).
                         DISCUSSION
                     I. Legal Standards
    An inventor can swear behind a reference by proving
he conceived his invention before the effective filing date
of the reference and was diligent in reducing his invention
to practice after that date. Perfect Surgical Techniques,
Inc. v. Olympus Am., Inc., 841 F.3d 1004, 1007 (Fed. Cir.
2016) (citing 35 U.S.C. § 102(g)1). It is well established,


   1    Congress amended § 102 in 2011 as part of the
America Invents Act (“AIA”). REG Synthetic Fuels, LLC
v. Neste Oil Oyj, 841 F.3d 954, 958 n.3 (Fed. Cir. 2016)
(citing Leahy-Smith America Invents Act, 125 Stat. 84,
341 (2011)). References to § 102 in this opinion refer to
the pre-AIA version of the statute, which applies here.
4                       APATOR MIITORS APS   v. KAMSTRUP A/S



however, that when a party seeks to prove conception
through an inventor’s testimony the party must proffer
evidence, “in addition to [the inventor’s] own statements
and documents,” corroborating the inventor’s testimony.
Mahurkar v. C.R. Bard, Inc., 79 F.3d 1572, 1577 (Fed.
Cir. 1996); Hahn v. Wong, 892 F.2d 1028, 1032 (Fed. Cir.
1989). While the requirement of corroboration exists to
prevent an inventor from “describ[ing] his actions in an
unjustifiably self-serving manner,” Chen v. Bouchard, 347
F.3d 1299, 1309 (Fed. Cir. 2003), “[e]ven the most credible
inventor testimony is a fortiori required to be corroborat-
ed by independent evidence,” Medichem, S.A. v. Rolabo,
S.L., 437 F.3d 1157, 1171-72 (Fed. Cir. 2006).
    The sufficiency of the proffered corroboration is de-
termined by a “rule of reason” analysis in which all perti-
nent evidence is examined. In re NTP, Inc., 654 F.3d
1279, 1291 (Fed. Cir. 2011). Even under the “rule of
reason” analysis, however, the “evidence of corroboration
must not depend solely on the inventor himself.” Cooper
v. Goldfarb, 154 F.3d 1321, 1330 (Fed. Cir. 1998); see also
Hahn, 892 F.2d at 1033 (corroborating evidence must be
“independent of information received from the inventor”).
     Conception is a question of law predicated on subsidi-
ary factual findings, one of which is the sufficiency of
corroboration. REG, 841 F.3d at 958. We review the
Board’s legal conclusions de novo and its factual findings
for substantial evidence.      Id.   Substantial evidence
“means such relevant evidence as a reasonable mind
might accept as adequate to support a conclusion,” Con-
sol. Edison Co. v. NLRB, 305 U.S. 197, 229 (1938), and
“the possibility of drawing two inconsistent conclusions
from the evidence” will not render the Board’s findings
unsupported by substantial evidence, Consolo v. Fed.
Mar. Comm’n, 383 U.S. 607, 620 (1966).
APATOR MIITORS APS   v. KAMSTRUP A/S                       5



                         II. Analysis
    Substantial evidence supports the Board’s finding
that    Apator    failed   to    sufficiently corroborate
Mr. Drachmann’s testimony of conception prior to the
effective filing date of Nielsen. Apator has failed to
proffer any evidence of Mr. Drachmann’s conception that
is not supported solely by Mr. Drachmann himself.
    In the first Tunheim email, for example,
Mr. Drachmann writes, “I have found the basis for the
mechanical assembly of the meter” including “several new
things that I didn’t have before.” J.A. 808. He writes, “[a]
sample is attached” and references “completely new
mechanical solutions (as seen in the picture).” J.A. 808.
The Drachmann Declaration then states that the first
Tunheim email attached the mechanics6 file. J.A. 795,
809.      Apator contends this evidence corroborates
Mr. Drachmann’s testimony that he conceived of the
meter depicted in the mechanics6 file by the February 15,
2010, date of the first Tunheim email and prior to Niel-
sen’s effective filing date. But as the Board noted, “there
are no indicia in either the body or header of the email
indicating a file is attached, let alone a file entitled ‘me-
chanics6’.” J.A. 13.
    In the second Tunheim email, Mr. Drachmann men-
tions “the latest presentation I put together” and states,
“I’m sending it to you here,” while the Bjerngaard email
mentions “UFM++” in its subject line and states, “here is
the presentation I promised.” J.A. 812, 836. The Drach-
mann Declaration then states that each of these emails
attached the UFM++ venture file. J.A. 795-96. Apator
contends this evidence corroborates Mr. Drachmann’s
testimony that he conceived of the meter depicted in the
UFM++ venture file by the March 22, 2010, dates of the
second Tunheim and Bjerngaard emails and prior to
Nielsen’s effective filing date. Again, as the Board ob-
served, “the only evidence that a ‘UFM++venture’ file was
6                         APATOR MIITORS APS   v. KAMSTRUP A/S



attached to these emails . . . is the Drachmann Declara-
tion,” that is, the testimony of Mr. Drachmann himself.
J.A. 13. None of the emails themselves indicate what file
was attached or what such attachment disclosed.
     The drawings proffered by Mr. Drachmann indicate
they were “[m]odified” on January 30, 2012, but the
Drachmann         Declaration     states,    based       on
Mr. Drachmann’s file naming convention, that these
drawings were actually created earlier, prior to Nielsen’s
effective filing date. J.A. 908, 796-98. Apator contends
this evidence shows Mr. Drachmann conceived of the
meter depicted in the drawings prior to Nielsen’s effective
filing date. Once more, as the Board noted, beyond the
Drachmann Declaration there is “no evidence showing the
existence or rules of Mr. Drachmann’s file naming conven-
tion [and] no evidence that [the drawings] were named
pursuant to that file naming convention.” J.A. 15.
    The evidence proffered by Mr. Drachmann is stuck in
a catch-22 of corroboration: Apator attempts to corrobo-
rate Mr. Drachmann’s testimony with the emails and the
drawings, but the emails and drawings can only provide
that corroboration with help from Mr. Drachmann’s
testimony. The first Tunheim email states that “[a]
sample is attached,” but we must rely on
Mr. Drachmann’s testimony to learn that the first Tun-
heim email has an attachment, and we must rely on his
testimony again to learn that that attachment is the
mechanics6 file. The second Tunheim and Bjerngaard
emails suffer from the same problem: while the emails
reference a “presentation,” it is only by resort to
Mr. Drachmann’s testimony that we can know either
email has an attachment and that attachment is the
UFM++ venture file. And without Mr. Drachmann’s
testimony otherwise, we cannot know that the drawings
were created any earlier than the January 30, 2012, date
indicated. As we stated in NTP, “[i]t would be strange
indeed to say that [an inventor], who filed the . . . affidavit
APATOR MIITORS APS   v. KAMSTRUP A/S                     7



that needs corroborating, can by his own testimony pro-
vide that corroboration.” NTP, 654 F.3d at 1292.
     Apator argues that Mr. Drachmann’s emails and
drawings, like unwitnessed laboratory notebooks, have
some corroborative value, citing Singh v. Brake, 222 F.3d
1362, 1370 (Fed. Cir. 2000). Apator is correct that,
“[u]nder a ‘rule of reason’ analysis, the fact that a note-
book entry” or other writing “has not been promptly
witnessed does not necessarily disqualify it in serving as
corroboration of conception.” Id. at 1369. Indeed, we
have permitted such writings to aid in corroborating
witness testimony alongside other, more persuasive,
evidence. See, e.g., Hybritech Inc. v. Monoclonal Antibod-
ies, Inc., 802 F.2d 1367, 1378 (Fed. Cir. 1986) (inventor
testimony of conception was sufficiently corroborated by
inventor’s laboratory notebook in which some entries were
witnessed before the critical date but others were not);
Mikus v. Wachtel, 542 F.2d 1157, 1161 (CCPA 1976)
(“Record of Invention” based on unwitnessed laboratory
notebook and witnessed before the critical date “may
supply evidence of conception”). But an unwitnessed
laboratory notebook, alone, cannot corroborate an inven-
tor’s testimony of conception. Brown v. Barbacid, 276
F.3d 1327, 1335 (Fed. Cir 2002) (“The Board did not err in
holding that an inventor’s own unwitnessed documenta-
tion does not corroborate an inventor’s testimony about
inventive facts.”); Procter & Gamble Co. v. Teva Pharms.
USA, Inc., 566 F.3d 989, 998-99 (Fed. Cir. 2009) (labora-
tory notebook that “was unwitnessed and was not corrob-
orated by any other evidence” could not corroborate
inventor     testimony    of   conception).       Likewise,
Mr. Drachmann’s unwitnessed emails and drawings,
alone, cannot corroborate his testimony of conception.
    It is no answer that Apator’s evidence is “unrebutted,”
as Apator repeatedly points out. This criticism misunder-
stands Apator’s burden of proof under § 102(g), which
requires that Apator prove Mr. Drachmann did conceive
8                       APATOR MIITORS APS   v. KAMSTRUP A/S



of his meter prior to Nielsen’s effective filing date, not
that Kamstrup prove Mr. Drachmann did not. In re
Magnum Oil Tools Int’l, Ltd., 829 F.3d 1364, 1375-76
(Fed. Cir. 2016) (“[I]n the context of establishing concep-
tion and reduction to practice for the purposes of estab-
lishing a priority date, . . . a patent challenger has the
burden of producing evidence to support a conclusion of
unpatentability under § 102 or § 103, but a patentee bears
the burden of establishing that its claimed invention is
entitled to an earlier priority date than an asserted prior
art reference.”) (emphasis added).
     In sum, a reasonable mind could conclude that Apator
failed to proffer evidence corroborating Mr. Drachmann’s
testimony regarding conception. Accordingly, we hold
that substantial evidence supports the Board’s finding
that Apator has not established conception prior to Niel-
sen’s effective filing date. Because conception has not
been established, we need not reach the issue of
Mr. Drachmann’s diligence in reducing his meter to
practice.
                       CONCLUSION
    Because Apator has not established conception prior
to Nielsen’s effective filing date, Apator cannot swear
behind Nielsen. Accordingly, we affirm the Board’s
determination that claim 2 is anticipated by Nielsen and
claim 10 is obvious over Nielsen and Körner.
                      AFFIRMED
                          COSTS
    No costs.
