Case: 20-1485 Document: 49 Page: 1 Filed: 01/19/2021
NOTE: This disposition is nonprecedential.
United States Court of Appeals
for the Federal Circuit
______________________
HAAG-STREIT AG,
Appellant
v.
EIDOLON OPTICAL, LLC,
Appellee
______________________
2020-1485
______________________
Appeal from the United States Patent and Trademark
Office, Patent Trial and Appeal Board in No. IPR2018-
01311.
______________________
Decided: January 19, 2021
______________________
RICHARD ERIC GAUM, Taft, Stettinius & Hollister, LLP,
Cleveland, OH, for appellant. Also represented by RYAN O.
WHITE, Indianapolis, IN.
JODI-ANN MCLANE, McInnes & McLane, LLP, Provi-
dence, RI, for appellee. Also represented by ALISSA
DIGMAN; JOHN T. MCINNES, Worcester, MA.
______________________
Case: 20-1485 Document: 49 Page: 2 Filed: 01/19/2021
2 HAAG-STREIT AG v. EIDOLON OPTICAL, LLC
Before LOURIE, O’MALLEY, and REYNA, Circuit Judges.
O’MALLEY, Circuit Judge.
Appellant Haag-Streit AG (“Haag-Streit”) filed a peti-
tion to institute an inter partes review (“IPR”) of certain
claims of U.S. Patent No. 6,547,394 B2 (“the ’394 patent”).
The Patent Trial and Appeal Board (“Board”) instituted re-
view and ultimately issued a final written decision finding
that Haag-Streit failed to prove that the challenged claims
were unpatentable under 35 U.S.C. § 103(a). Haag-Streit
AG v. Eidolon Optical, LLC, No. IPR2018-01311, 2019 Pat.
App. LEXIS 13545 (P.T.A.B. Dec. 19, 2019) (“Board Deci-
sion”). Haag-Streit appeals the Board’s final written deci-
sion, challenging the Board’s assessment of the evidence.
For the reasons explained below, we affirm.
BACKGROUND
Eidolon Optical, LLC (“Eidolon”) owns, by assignment,
the ’394 patent, which relates to “a device which is used to
illuminate a patient’s eye that has been administered with
a fluorescent dye for the purpose of examining the eye for
epithelial defects.” ’394 patent, col. 1, ll. 48–51. The patent
explains that “current technology utilizes a battery oper-
ated hand-held penlight illuminator in conjunction with a
solution of Sodium Fluorescein.” Id. at col. 1, ll. 14–16. The
existing prior art device “typically uses conventional bat-
teries as a power source and an incandescent or halogen
light bulb . . . [with a] cobalt blue filter attached over the
lamp [that] filters the white light emitted by the bulb to
produce a blue beam.” Id. at col. 1, ll. 19–22. “This blue
beam is used to illuminate the patient’s eye after applica-
tion of the Sodium Fluorescein dye.” Id. at col. 1, ll. 22–24.
According to ’394 patent, “[t]he invention in its sim-
plest form utilizes four components: a battery, an electrical
resistor, an electrical switch and a blue light emitting diode
[‘LED’].” Id. at col. 1, ll. 51–53. Figure 1, below, depicts
“an electrical schematic of an ophthalmic illuminator
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HAAG-STREIT AG v. EIDOLON OPTICAL, LLC 3
utilizing a blue LED source, according to the invention.”
Id. at col. 1, ll. 56–58.
Describing Figure 1, the ’394 patent discloses that,
“when the switch 12 is closed[,] electrical energy from the
battery 14 flows through the circuit 10 and causes the blue
LED 16 to produce blue light 18.” Id. at col. 2, ll. 7–10. The
patent also discloses that “resistor 20 is used to limit the
current that is applied to the LED 16 as per the manufac-
turer specification[,] which is typically 20 to 30 milli-
amps.” Id. at col. 2, ll. 10–12.
According to the ’394 patent, the device depicted in Fig-
ure 1 is “superior to the current incandescent technology”
because: (1) “the blue LED 16 emits more illumination in
the desired blue spectrum (425 to 475 NM) than the filtered
incandescent lamp which results in more fluorescence of
the fluorescein dyed eye 22 and thus has better sensitivity;”
(2) “the blue LED 18 uses less power than a blue optically
filtered incandescent or halogen bulb so that the battery
power source 14 should last significantly longer;” and
(3) “the invention is simpler to the prior art technology in
that there is no need for a blue bandpass optical filter.” Id.
at col. 2, ll. 25–35.
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4 HAAG-STREIT AG v. EIDOLON OPTICAL, LLC
Of the challenged claims, claims 1 and 15 are independ-
ent. Claims 5, 6, 8–10, and 14 depend from claim 1, and
claims 16 and 19 depend from claim 15. Claim 1 recites:
1. An ophthalmic illuminator, comprising:
a battery;
an electrical resistor in circuit with the battery;
an electrical switch in circuit with the resistor;
at least one light emitting diode, in circuit with the
switch, for generating blue light energy in response
to activation of the switch; and
a fluorescein dye administered to a patient’s eye,
the dye being responsive to the energy to fluoresce.
’394 patent, col. 4, ll. 10–21. Claim 15 recites:
A method for illuminating a patient’s eye for oph-
thalmic examination, comprising the steps of: ad-
ministering a fluorescein dye to the patient’s eye,
illuminating the eye with blue light energy gener-
ated from one or more light emitting diodes, the dye
being responsive to the blue light energy to fluo-
resce, and viewing the patient’s eye, and viewing
the eye while the dye fluoresces.
Id. at col. 5, ll. 1–7.
Haag-Streit petitioned for IPR of claims 1, 5, 6, 8–10,
14–16, and 19 of the ’394 patent. In relevant part, Haag-
Streit challenged claims 1, 5, 6, 8–10, 14, and 19 as obvious
in light of European Patent Application 0 554 643 A1 (“Lon-
gobardi”), which was filed on February 5, 1992. J.A. 64–
76. Longobardi discloses “an apparatus for visualizing an
object and/or recording images of said object under low
lighting conditions.” Longobardi, col. 1, ll. 3–5. One dis-
closed application for the apparatus is for retinal or cho-
roidal angiography. Id. at Abstract. Figure 1 of
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HAAG-STREIT AG v. EIDOLON OPTICAL, LLC 5
Longobardi, reproduced below, depicts “a diagram of a pos-
sible embodiment of the device for retinal angiography[:]”
Id. at col. 8, ll. 4–5. Figure 1 shows a device for retinal
angiography having “a continuous light source 1 of low
power, for example 20 W electric,” a “filter support ring 7,”
which “may be fitted with various interference filters to be
used for various types of observation,” and an “image in-
tensifier 19,” which “amplifies the image.” Id. at col. 8, ll.
15–50. Figure 1 shows filter support ring 7 as including
five filters (shown as circles). Longobardi explains that the
filters are used with various tracers, such as fluorescein
and indocyanine green, to observe “the various layers of the
fundus of the eye.” Id. at col. 8, ll. 23–27. Longobardi fur-
ther explains that, “[f]or retinal fluoroscopic angiography,
two filters are normally used: one transmits blue light be-
tween 465 and 490 nm, representing the absorption peak
of the excitation of fluorescein; the other transmits between
525 and 530 nm, where the emission peak of fluorescein is
located.” Id. at col. 4, ll. 7–15.
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6 HAAG-STREIT AG v. EIDOLON OPTICAL, LLC
Figure 1A of Longobardi, reproduced below, depicts “a
diagram of a modified embodiment[:]”
Id. at col. 8, l. 6. In the Figure 1A embodiment, “a light
source consisting of ‘a set of three [LEDs] 1A, 1B, 1C’ re-
places continuous light source 1, filter support ring 7, and
mirror 9 from the Figure 1 embodiment.” Board Decision,
2019 Pat. App. LEXIS 13545, at *17 (quoting Longobardi,
col. 9, ll. 39–43)).
The Board instituted review. After briefing and oral
argument, the Board issued its final written decision find-
ing that Haag-Streit failed to show that the asserted claims
are unpatentable. In doing so, the Board explained that
claim 1 requires “at least one light emitting diode . . . for
generating blue light energy” (the “‘blue light energy’ limi-
tation”), and construed that limitation to require that the
“light emitting diode” or LED “itself generates ‘blue light
energy.’” Id. at *19–20 (quoting ’394 patent, col. 4, ll. 17–
19). While both parties agreed that Longobardi does not
expressly disclose the “blue light energy” limitation, Haag-
Streit argued that Longobardi “implicitly discloses a blue
LED.” Id. at *20–21. In particular, Haag-Streit argued
that “Longobardi teaches making the same invention of
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HAAG-STREIT AG v. EIDOLON OPTICAL, LLC 7
Fig. 1 using LEDs, as shown in Fig. 1A, which expressly
includes fluorescence wavelengths for sodium fluorescein,
i.e., blue light.” Id. at *29.
The Board rejected Haag-Streit’s argument “that one
of ordinary skill in the art would have understood Longo-
bardi as implicitly disclosing the presence of a blue LED
with sufficient power output to cause sodium fluorescein to
fluoresce.” Id. Specifically, the Board found that: (1) “[t]he
invention taught in Fig. 1A is more limited than the inven-
tion taught in Fig. 1[,]” such that the two embodiments do
not depict “identical embodiments of the same invention
with different light sources;” (2) “none of the declaration
testimony of [Haag-Streit’s expert] Dr. Jiao supports [the]
position” that Longobardi “implicitly disclos[es] the pres-
ence of a blue LED;” and (3) Haag-Streit “has not ade-
quately demonstrated that a blue LED with sufficient
power output to cause sodium fluorescein to fluoresce ex-
isted as of February 5, 1992”—which the parties agreed “is
the relevant point in time to assess the alleged implicit dis-
closures in Longobardi.” Id. at *30–34.
Given these findings, the Board concluded that Haag-
Streit failed to establish the existence, as of February 5,
1992, “of a blue LED having sufficient power output to
cause sodium fluorescein to fluoresce,” and further failed to
show “that Longobardi would have been understood by one
of ordinary skill in the art as implicitly disclosing the ‘blue
light energy’ limitation.” Id. at *41. As such, the Board
found that Haag-Streit “has not demonstrated by a prepon-
derance of the evidence that claim 1 would have been obvi-
ous based on Longobardi and Devonshire.” Id. 1
1 Before the Board, Haag-Streit asserted that claims
1, 5, 6, 8–10, 14, and 19 were obvious in light of Longobardi
and GB 2 077 946 A (“Devonshire”), published Decem-
ber 23, 1981. Board Decision, 2019 Pat. App. LEXIS
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8 HAAG-STREIT AG v. EIDOLON OPTICAL, LLC
Haag-Streit timely appealed. We have jurisdiction un-
der 28 U.S.C. § 1295(a)(4)(A).
DISCUSSION
Obviousness is a question of law based on underlying
findings of fact, including the scope and content of the prior
art, differences between the prior art and the claimed in-
vention, the level of ordinary skill in the art, and any ob-
jective evidence of nonobviousness. KSR Int’l Co. v.
Teleflex Inc., 550 U.S. 398, 406 (2007). Although the
Board’s ultimate conclusion that the claims are not obvious
is a legal determination subject to de novo review, we re-
view the Board’s subsidiary factual findings for substantial
evidence. Intelligent Bio-Sys., Inc. v. Illumina Cambridge
Ltd., 821 F.3d 1359, 1366 (Fed. Cir. 2016).
Under 35 U.S.C. § 103, a prior art reference “must be
considered not only for what it expressly teaches, but also
for what it fairly suggests.” In re Burckel, 592 F.2d 1175,
1179 (C.C.P.A. 1979); see also In re Lamberti, 545 F.2d 747,
750 (C.C.P.A. 1976) (“[T]he question under 35 U.S.C. § 103
is not merely what the references expressly teach, but what
they would have suggested to one of ordinary skill in the
art at the time the invention was made.”). Whether a per-
son of ordinary skill in the art would view a prior art refer-
ence as containing an implicit disclosure is a question of
fact, which we review for substantial evidence. See IXI IP,
LLC v. Samsung Elecs. Co., 903 F.3d 1257, 1262–65 (Fed.
Cir. 2018) (“We conclude that substantial evidence sup-
ports the Board’s finding” of implicit disclosure in a prior
art reference).
On appeal, Haag-Streit argues that the Board erred in
finding that Longobardi does not implicitly disclose a blue
13545, at *6, n.5. On appeal, Haag-Streit does not chal-
lenge any of the Board’s findings with respect to Devon-
shire.
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HAAG-STREIT AG v. EIDOLON OPTICAL, LLC 9
LED having sufficient power to cause sodium fluorescein to
fluoresce. According to Haag-Streit, the Board: (1) misin-
terpreted Longobardi in holding that the invention shown
in Figure 1A is more limited than the invention shown in
Figure 1; (2) erred in finding that none of Dr. Jiao’s testi-
mony supported the position that one of ordinary skill
would have understood Longobardi as implicitly disclosing
a blue LED; and (3) erred in finding that Haag-Streit failed
to establish that, as of February 5, 1992, blue LEDs had
sufficient output power to cause sodium fluorescein to flu-
oresce. As explained below, we conclude that substantial
evidence supports the Board’s findings.
First, as noted, the Board disagreed with Haag-Streit’s
argument that Figure 1 and Figure 1A of Longobardi depict
“‘identical embodiments of the same invention with differ-
ent light sources’—i.e., a continuous light source and filter
providing blue light in the context of the Figure 1 embodi-
ment and an LED generating blue light in the Figure 1A
embodiment.” Board Decision, 2019 Pat. App. LEXIS
13545, at *29–30. Instead, the Board was persuaded that
“[t]he invention taught in Fig. 1A is more limited than the
invention taught in Fig. 1.” Id. In reaching this conclusion,
the Board explained that Figure 1 of Longobardi is “di-
rected to a non-LED light source and does not teach that
there is any limitation to the number of filters that can be
employed,” whereas “Longobardi expressly teaches that
Fig. 1A is limited to only three LEDs.” Id. And, although
it recognized that Longobardi does “state that the Figure
1A embodiment includes several structures identical to
those in Figure 1,” the Board found that Haag-Streit “has
not persuasively shown that one of ordinary skill in the art
would have understood this to also indicate that these em-
bodiments share all the same functionality, including, for
example, the presence of blue light to cause sodium fluo-
rescein to fluoresce.” Id. at *30–31.
Substantial evidence supports the Board’s factual find-
ing that one of ordinary skill in the art would not
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10 HAAG-STREIT AG v. EIDOLON OPTICAL, LLC
understand the functionality of Figure 1 and Figure 1A of
Longobardi to be the same. Haag-Streit argued that Lon-
gobardi teaches making the same invention of Figure 1 us-
ing LEDs shown in Figure 1A, and that this substitution
would “include[] a blue light LED to cause the most com-
mon tracer substance, sodium fluorescein, to fluoresce.”
Appellant’s Br. 32. But the Board agreed with Eidolon that
Figure 1 of Longobardi is directed to a non-LED light
source, and discloses “the use of tracers other than sodium
fluorescein (e.g., indocyanine green) for use with the Figure
1 embodiment,” whereas Figure 1A is limited to three
LEDs. Board Decision, 2019 Pat. App. LEXIS 13545, at
*30–31.
The Board carefully considered Longobardi as a whole,
as well as the competing expert testimony, and concluded
that one of ordinary skill in the art would not have under-
stood the embodiments shown in Figure 1 and Figure 1A to
be identical embodiments of the same invention with a dif-
ferent light source and the same functionality. Id. at *28–
31. We decline to reweigh that evidence on appeal. In re
NTP, Inc., 654 F.3d 1279, 1292 (Fed. Cir. 2011) (“This court
does not reweigh evidence on appeal, but rather deter-
mines whether substantial evidence supports the Board’s
fact findings.”). Instead, we conclude that, on this record,
the Board’s determination that the invention taught in Fig-
ure 1A is more limited than the invention taught in Fig-
ure 1, is supported by substantial evidence.
Second, the Board found that Dr. Jiao’s testimony did
not support the position that one of ordinary skill in the art
would have understood Longobardi to implicitly disclose
the presence of a blue LED. In particular, the Board found
that none of Dr. Jiao’s testimony “actually addresses the
state of the art of blue LEDs in 1992, which, as acknowl-
edged by [Haag-Streit], is the relevant point in time to as-
sess the alleged implicit disclosures in Longobardi.” Board
Decision, 2019 Pat. App. LEXIS 13545, at *33. The Board
explained that, although Dr. Jiao’s original declaration
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HAAG-STREIT AG v. EIDOLON OPTICAL, LLC 11
filed with the IPR petition stated that “one of ordinary skill
in the art ‘would understand Longobardi’s teaching of us-
ing fluorescein for imaging purposes [to] necessarily
mean[] that the instrument emits blue light’” he failed to
“adequately support the view that one of ordinary skill in
the art would have understood Longobardi to implicitly dis-
close the presence of a blue LED.” Id. at *33. Indeed, the
Board noted that Dr. Jiao’s testimony on this issue “makes
no reference to a blue LED.” Id.
On appeal, Haag-Streit argues that the Board’s finding
that “none of Dr. Jiao’s testimony supports the contention
that Longobardi implicitly discloses a blue LED” is incon-
sistent with findings the Board made in its Institution De-
cision. Appellant’s Br. 34. But it is well established that
“the Board is not bound by any findings made in its Insti-
tution Decision.” TriVascular, Inc. v. Samuels, 812 F.3d
1056, 1068 (Fed. Cir. 2016) (explaining that, at the institu-
tion phase, “the Board is considering the matter prelimi-
narily without the benefit of a full record”). In any event,
we disagree with Haag-Streit’s assertion that the Board’s
findings in the Institution Decision are inconsistent with
those in its final written decision.
In the Institution Decision, the Board never said that
Dr. Jiao’s testimony supports the position that one of ordi-
nary skill in the art would have understood Longobardi to
implicitly disclose the presence of a blue LED. Instead, the
Board acknowledged that “Petitioner (via Dr. Jiao) [took]
the position that one of ordinary skill in the art would view
Longobardi as at least implicitly teaching or suggesting the
use of a blue LED to generate blue light energy,” while “Pa-
tent Owner (via Dr. Lebby) [took] the position that blue
LEDs did not exist at the time for medical use and that one
of ordinary skill in the art would not have used a blue LED
for medical use.” Haag-Streit AG v. Eidolon Optical, LLC,
No. IPR2018-01311, 2019 WL 171684, at *10 (P.T.A.B. Jan.
11, 2019). The Board found that this conflicting testimony
created a genuine issue of material fact which, at that stage
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12 HAAG-STREIT AG v. EIDOLON OPTICAL, LLC
in the proceedings, had to be viewed in the light most fa-
vorable to Haag-Streit. Id.
In its final written decision, the Board carefully consid-
ered Dr. Jiao’s declarations, but agreed with Eidolon’s evi-
dence and argument in finding that his testimony failed to
demonstrate that one of ordinary skill in the art would
have understood Longobardi to implicitly disclose the pres-
ence of a blue LED. Board Decision, 2019 Pat. App. LEXIS
13545, at *31–33. “[I]t is not for us to second-guess the
Board’s assessment of the evidence.” Velander v. Garner,
348 F.3d 1359, 1378–79 (Fed. Cir. 2003) (“Our task is to
determine whether substantial evidence supports the con-
clusion chosen by the Board.”).
Finally, the Board found that Haag-Streit did not carry
its burden to establish that “a blue LED with sufficient
power output to cause sodium fluorescein to fluoresce ex-
isted as of February 5, 1992.” Board Decision, 2019 Pat.
App. LEXIS 13545, at *34. On this point, Eidolon pre-
sented expert testimony that, “[a]t the time of Longobardi,
1992, an LED capable of generating blue light energy suit-
able for diagnostic medical applications such as retinal an-
giography simply did not exist.” Id. at *34–35. The Board
found that this evidence shifted the burden of production
to Haag-Streit to establish that blue LEDs sufficient to ex-
cite sodium fluorescein existed as of February 5, 1992. Id.
at *35–36. Haag-Streit’s expert, Dr. Jiao, admitted that he
did not know the specific amount of power output needed
for an LED to cause sodium fluorescein to fluoresce. Id. at
*38–39. “Without knowing the amount of power necessary
to cause sodium fluorescein to fluoresce,” the Board found
that Haag-Streit could not carry its burden on this issue.
Id. at *39. Given the evidence, the Board found that Haag-
Streit did not meet its burden to establish that, as of Feb-
ruary 5, 1992, blue LEDs with sufficient power existed. Id.
at *41.
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HAAG-STREIT AG v. EIDOLON OPTICAL, LLC 13
On appeal, Haag-Streit points to three different refer-
ences to argue that blue LEDs existed as of 1992. Appel-
lant’s Br. 12–15. As noted, however, the relevant inquiry
before the Board was whether blue LED with sufficient
power output to cause sodium fluorescein to fluoresce ex-
isted as of February 5, 1992. Board Decision, 2019 Pat.
App. LEXIS 13545, at *27. The Board carefully considered
the parties’ competing evidence and testimony in finding
that Haag-Streit failed to meet its burden on this issue. In
doing so, the Board refused to consider an exhibit Haag-
Streit sought to rely upon for the first time during oral ar-
gument. Id. at *36–37. That evidentiary determination
was within the Board’s discretion, and we decline to dis-
turb it on appeal. Belden Inc. v. Berk-Tek LLC, 805 F.3d
1064, 1078 (Fed. Cir. 2015) (“We review the Board’s eviden-
tiary ruling for abuse of discretion, which may be found if
the Board violated governing law.”); see Dell Inc. v. Accel-
eron, LLC, 884 F.3d 1364, 1369 (Fed. Cir. 2018) (noting
that, absent exercise of its waiver authority, “the Board
was obligated to dismiss [the petitioner’s] untimely argu-
ment . . . raised for the first time during oral argument”).
Haag-Streit also argues that the Board erred in “disre-
garding the Hartnett reference from 1994.” Appellant’s Br.
21. Review of the Board’s decision reveals that it did, in
fact, consider that reference, but found that it: (1) did not
reflect the state of the art as of 1992; and (2) disclosed “the
use of a laser, not a blue LED.” Board Decision, 2019 Pat.
App. LEXIS 13545, at *41. We decline to reweigh that ev-
idence on appeal.
On this record, substantial evidence supports the
Board’s factual finding that Haag-Streit did not prove by a
preponderance of the evidence that Longobardi implicitly
discloses the “blue light energy” limitation of claims 1 and
15 of the ’394 patent.
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14 HAAG-STREIT AG v. EIDOLON OPTICAL, LLC
CONCLUSION
We have considered Haag-Streit’s remaining argu-
ments, but find them unpersuasive. For the foregoing rea-
sons, we affirm the Board’s final written decision.
AFFIRMED