Carucel Investments, LP

Patent Trials and Appeals Board

Nov 20, 2020

IPR2019-01101 (P.T.A.B. Nov. 20, 2020)

Trials@uspto.gov Paper 31
571-272-7822 Entered: November 20, 2020

UNITED STATES PATENT AND TRADEMARK OFFICE

BEFORE THE PATENT TRIAL AND APPEAL BOARD

VOLKSWAGEN GROUP OF AMERICA, INC.,
Petitioner,
v.
CARUCEL INVESTMENTS, L.P.,
Patent Owner.

IPR2019-011011
Patent 7,221,904 B1

Before THOMAS L. GIANNETTI, DANIEL J. GALLIGAN, and
PAUL J. KORNICZKY, Administrative Patent Judges.
GALLIGAN, Administrative Patent Judge.

JUDGMENT
Final Written Decision
Determining All Challenged Claims Unpatentable
35 U.S.C. § 318(a)

1 IPR2019-01573 has been consolidated with the instant proceeding.
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I. INTRODUCTION
In this inter partes review, Volkswagen Group of America, Inc.
(“Petitioner”) challenges the patentability of claims 22, 23, 28–35, 40, 50,
51, and 56–59 of U.S. Patent No. 7,221,904 B1 (“the ’904 patent,”
Ex. 1001), which is assigned to Carucel Investments, L.P. (“Patent Owner”).
We have jurisdiction under 35 U.S.C. § 6. This Final Written
Decision, issued pursuant to 35 U.S.C. § 318(a), addresses issues and
arguments raised during the trial in this inter partes review. For the reasons
discussed below, we determine that Petitioner has proven by a
preponderance of the evidence that claims 22, 23, 28–35, 40, 50, 51, and 56–
59 of the ’904 patent are unpatentable. See 35 U.S.C. § 316(e) (“In an inter
partes review instituted under this chapter, the petitioner shall have the
burden of proving a proposition of unpatentability by a preponderance of the
evidence.”).
A. Procedural History
On May 20, 2019, Petitioner requested inter partes review of claims
22, 23, 28–35, 40, 50, and 51 of the ’904 patent on the following grounds:
Claims Challenged 35 U.S.C. § References/Basis
22, 23, 28–35, 40, 50, 51 103(a)2 Gilhousen865,3 Gilhousen3904
22, 23, 28, 29, 32–35,
40, 50, 51
103(a) Vercauteren,5 Forssén6

2 The Leahy-Smith America Invents Act (“AIA”) included revisions to
35 U.S.C. §§ 102 and 103 that became effective after the filing of the
application for the ’904 patent. Therefore, we apply the pre-AIA versions of
these sections.
3 Gilhousen, US 5,559,865, issued Sept. 24, 1996 (Ex. 1005).
4 Gilhousen, US 5,109,390, issued Apr. 28, 1992 (Ex. 1006).
5 Vercauteren, US 5,504,935, issued Apr. 2, 1996 (Ex. 1007).
6 Forssén, US 5,566,209, issued Oct. 15, 1996 (Ex. 1008).
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Claims Challenged 35 U.S.C. § References/Basis
30, 31 103(a) Vercauteren, Forssén,
Gilhousen390
Paper 27 (“Pet.”), 5–6. Patent Owner filed a Preliminary Response. Paper 6
(“Prelim. Resp.”). We instituted trial on all grounds of unpatentability.
Paper 7 (“Inst. Dec.”), 20.
On September 5, 2019, Petitioner requested inter partes review of
claims 56–59 of the ’904 patent on the following grounds:
Claim(s) Challenged 35 U.S.C. § Reference(s)/Basis
56 103(a) Gilhousen865
57–59 103(a) Gilhousen865, Gilhousen390
56 103(a) Vercauteren
57, 58 103(a) Vercauteren, Gilhousen390
59 103(a) Vercauteren, Gilhousen390,
Forssén
IPR2019-01573, Paper 2 (“1573 Pet.”), 6. Patent Owner filed a Preliminary
Response. IPR2019-01573, Paper 6. We instituted trial on all grounds of
unpatentability. IPR2019-01573, Paper 7, 16.
After institution of trial in IPR2019-01573, we consolidated
IPR2019-01573 with IPR2019-01101 and terminated IPR2019-01573.
Paper 11.
During the trial, Patent Owner filed a Response (Paper 19, “PO
Resp.”), Petitioner filed a Reply (Paper 22, “Pet. Reply”), and Patent Owner
filed a Sur-reply (Paper 26, “PO Sur-reply”).
An oral hearing was held on September 2, 2020, a transcript of which
appears in the record. Paper 30 (“Tr.”).

7 Citations to the record are to IPR2019-01101 unless indicated otherwise by
“IPR2019-01573” or by the prefix “1573.”
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B. Related Matters
As required by 37 C.F.R. § 42.8(b)(2), the parties identify various
related matters. Pet. 2–3; Paper 4. The ’904 patent is also the subject of
IPR2019-01298 and IPR2019-01635.8
The ’904 patent was asserted in Carucel Investments, LP v. Novatel
Wireless, Inc., 16-cv-118 (S.D. Cal.) (“the Novatel litigation”), resulting in a
jury verdict of non-infringement. See Ex. 2106, 2–5 (Order denying
Carucel’s motion for JMOL or new trial).
C. Real Parties in Interest
The parties identify themselves as the real parties in interest. Pet. 2;
Paper 4.
D. The ’904 Patent and Illustrative Claim
The ’904 patent relates to cellular telephone systems and states that
“[a] problem with existing mobile telephone systems is the considerable
time required in handoffs,” which is the process by which a mobile unit is
transferred from one cell site to another as it moves through a network.
Ex. 1001, 1:16–20, 1:34–41, 1:51–52. According to the ’904 patent, in
urban areas the number of cells is increased and cell size is decreased to
accommodate more users. Ex. 1001, 1:55–62. The ’904 patent states that a
drawback of reducing cell size is that mobile units cross cell boundaries
more often, requiring more handoffs. Ex. 1001, 1:62–67.
To address this purported problem, the ’904 patent proposes a system
having moving base stations that move in the direction of traffic along a
roadway. Ex. 1001, code (57). The moving base stations are interposed

8 IPR2019-01635 was consolidated with IPR2019-01298. IPR2019-01298,
Paper 13, 3 n.2.
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between mobile units and fixed base stations. Ex. 1001, 3:18–22. The ’904
patent states that, “because of movement of the base station in the same
direction as the traveling mobile unit, the number of handoffs is greatly
reduced.” Ex. 1001, 5:17–19.
Challenged claim 22 is illustrative and recites the following:
An apparatus adapted to move in accordance with a
movement of a mobile unit moving relative to a plurality of fixed
radio ports, the apparatus comprising:
a receiver adapted to receive a plurality of signals, each of
the plurality of signals transmitted from each of the plurality of
fixed radio ports within a frequency band having a lower limit
greater than 300 megahertz;
a transmitter adapted to transmit, within the frequency
band, a resultant signal to the mobile unit in accordance with at
least one of the plurality of signals; and
a processor adapted to maximize an amount of transferred
information to the mobile unit by evaluating a quality of each of
the plurality of signals transmitted from the plurality of fixed
radio ports.

II. ANALYSIS
A. Level of Ordinary Skill in the Art
Petitioner contends that a person of ordinary skill in the art would
have had “a B.S. degree in Computer Science, Electrical Engineering, or an
equivalent field, as well as at least 2-3 years of academic or industry
experience in mobile wireless communications, or comparable industry
experience.” Pet. 14 (citing Ex. 1003 (Declaration of Dr. Zhi Ding) ¶¶ 24–
25).
Patent Owner contends a person of ordinary skill in the art
at or near the filing date of the earliest priority application of the
‘904 Patent would have had (i) a Bachelor of Science degree in
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electrical engineering or computer engineering or related field of
study; (ii) at least two years of experience with wireless
communications systems; and (iii) would also be familiar with
cellular communication technology.
PO Resp. 8–9 (citing Ex. 2100 (Declaration of Mark R. Lanning) ¶ 54).
Further, Patent Owner contends that “[a] lack of experience can be
compensated with additional education and a lack of education can be
compensated with additional work experience.” PO Resp. 9.
The formulations differ slightly, in that Patent Owner’s formulation
specifically calls for familiarity with cellular communication technology,
whereas Petitioner’s formulation is more general, requiring a comparable
level of experience with mobile wireless communications.
We regard these formulations as not materially different, however,
because familiarity with mobile wireless communications would normally
include knowledge of cellular communication technology. Both definitions
are also consistent with the prior art before us and with the level of skill
reflected in the ’904 patent. See Okajima v. Bourdeau, 261 F.3d 1350, 1355
(Fed. Cir. 2001) (prior art itself may reflect an appropriate level of skill). As
the definitions are not materially different, we adopt Patent Owner’s more
specific description, with the exception of the open-ended language “at
least.” However, we would reach the same result on the ultimate question of
obviousness of the ’904 patent under either formulation.
B. Claim Interpretation
In an inter partes review for a petition filed on or after November 13,
2018, a claim “shall be construed using the same claim construction standard
that would be used to construe the claim in a civil action under
35 U.S.C. 282(b).” See Changes to the Claim Construction Standard for
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Interpreting Claims in Trial Proceedings Before the Patent Trial and Appeal
Board, 83 Fed. Reg. 51,340 (Oct. 11, 2018) (amending 37 C.F.R.
§ 42.100(b) effective November 13, 2018) (now codified at 37 C.F.R.
§ 42.100(b) (2019)).9 In applying this claim construction standard, we are
guided by the principle that the words of a claim “are generally given their
ordinary and customary meaning” as understood by a person of ordinary
skill in the art in question at the time of the invention. Phillips v. AWH
Corp., 415 F.3d 1303, 1312–13 (Fed. Cir. 2005) (en banc) (citation omitted).
“In determining the meaning of the disputed claim limitation, we look
principally to the intrinsic evidence of record, examining the claim language
itself, the written description, and the prosecution history, if in evidence.”
DePuy Spine, Inc. v. Medtronic Sofamor Danek, Inc., 469 F.3d 1005, 1014
(Fed. Cir. 2006) (citing Phillips, 415 F.3d at 1312–17). There is a “heavy
presumption” that a claim term carries its ordinary and customary meaning.
CCS Fitness, Inc. v. Brunswick Corp., 288 F.3d 1359, 1366 (Fed. Cir. 2002)
(citation omitted).
Initially, neither party proposed any claim constructions for our
consideration. Pre-institution, Petitioner contended that “all claim terms
should receive their plain and ordinary meaning, in the context of the ’904
patent specification, under the Phillips standard.” Pet. 14–15; 1573 Pet. 15.
In the Preliminary Response, Patent Owner stated that the Board “need not
construe any claim term in a particular manner in order to arrive at the
conclusion that the Petition is procedurally and substantively deficient.”
Prelim. Resp. 3; IPR2019-01573, Paper 6, 5–6. In our Institution Decisions,

9 The petitions in both IPR2019-01101 and IPR2019-01573 were filed after
the effective date of the change to the claim construction standard.
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we did not see the need to construe any terms. Inst. Dec. 5; IPR2019-01573,
Paper 7, 8–9.
Post-institution, both parties have proposed claim constructions for
our consideration. Thus, Patent Owner now seeks construction of the
following terms appearing in the challenged claims: “fixed port,” “fixed
radio ports,” “adapted to,” and “mobile unit.” PO Resp. 10–16. Several of
these terms were construed by the district court in the Novatel litigation. See
Ex. 2105 (claim construction order). Petitioner has responded with a
construction of “mobile unit.” Pet. Reply 3–8.
1. “fixed port,” “fixed radio port”
Patent Owner proposes that we adopt the district court’s construction
of these terms in the Novatel litigation, which are as follows: “fixed port”—
“a stationary device at which signals can enter and exit a communication
network”; “fixed radio port”—“stationary devices that each transmit and
receive radio frequency signals to provide access to a communication
network.” PO Resp. 10–11; see Ex. 2105, 12. Petitioner contends there is
no need to provide constructions for these terms to resolve a controversy.
Pet. Reply 2 (citing Vivid Techs., Inc. v. Am. Sci. & Eng’g, Inc., 200 F.3d
795, 803 (Fed. Cir. 1999)). We agree with Petitioner that no construction of
these terms is necessary.
2. “adapted to”
In the Novatel litigation, the district court construed “adapted to,”
appearing in the preambles of claims 22 and 34, as “constructed to move
with the traffic at a rate of speed which is comparable to the speed of the
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traffic.” Ex. 2105, 14–16.10 Patent Owner contends that the preamble is
limiting and urges us to adopt this construction. PO Resp. 11–13. Petitioner
states that this construction “is consistent with the district court’s order” and
does not dispute this construction. Pet. Reply 2. However, Petitioner
disagrees with what it terms an “even narrower construction” of this term,
implied by Patent Owner’s arguments. Pet. Reply 2–3. That dispute centers
around the meaning of “traffic,” a term that does not appear in the claims but
does appear in the district court’s construction of “adapted to.” Patent
Owner relies on this proposed further limitation to the district court’s
construction in discussing the prior art Gilhousen865 patent, where Patent
Owner states: “An airplane does not move with traffic as it is not bound to
predetermined roads.” PO Resp. 44; see also PO Sur-reply 19–20.
Based on the parties’ agreement with the district court’s construction,
we apply that construction in our analysis below.11 Furthermore, we discuss
the “narrower implied construction” of the term “traffic” advanced by Patent
Owner in the analysis of Gilhousen865 below.
3. “mobile unit”
Prior to our Institution Decision, neither party advanced a construction
for this term, which now lies at the center of this controversy.
Post-institution, Patent Owner argues: “A mobile unit is more than just a
cordless phone handset.” PO Resp. 13. Thus, Patent Owner would have us
construe “mobile unit” narrowly, as “a device that must register with and be

10 The phrase “adapted to” appears in the bodies of claims 22 and 34 as well,
but the district court’s construction focuses on the “adapted to move”
language of the preamble. Ex. 2105, 14–16.
11 We do not express an opinion on the question of whether the preamble is
limiting as that is not necessary to resolve a controversy.
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able to directly communicate with the cellular network.” PO Resp. 13.
Patent Owner asserts that this includes the “capability to be switched back-
and-forth between either a direct connection with the fixed base station or a
connection with a moving base station.” PO Resp. 13.
To support this construction, Patent Owner relies on the ’904 patent
specification: “The ’904 Patent specification teaches that a mobile unit must
be capable of directly communicating with either a fixed cellular base station
or a moving base station.” PO Resp. 13 (citing Ex. 1001, 4:48–51).
According to Patent Owner, “the mobile unit’s capability to be switched
back-and-forth between either a direct connection with the fixed base station
or a connection with a moving base station is discussed repeatedly and
throughout the specification.” PO Resp. 13 (citing Ex. 1001, 11:1–7).
Patent Owner cites also the discussion of the mobile unit in the ’904 patent,
which describes registration:
When a mobile unit set is first powered up or first enters a
service area, the mobile unit must register in the manner
described earlier, by transmitting its unique address in the new
service area. The address will be received by the closest moving
base station 30 and transmitted via a fixed radio port and the
gateway switch 60 to the telephone network.
Ex. 1001, 9:62–67 (partially quoted at PO Resp. 14). Patent Owner also
relies on testimony from its expert, Mr. Lanning. See PO Resp. 13–15
(citing Ex. 2100 ¶¶ 53, 60–65, 70–74).
Petitioner responds that no special construction of “mobile unit” is
necessary and opposes Patent Owner’s construction on a number of grounds.
Pet. Reply 3–8. In summary, Petitioner asserts that Patent Owner’s
argument for a special construction is inconsistent with Patent Owner’s
position in the Novatel litigation. Pet. Reply 4; Ex. 2105, 20 (“In its opening
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claim construction brief, [Carucel] states that it no longer requests
construction of the term ‘mobile unit.’”). Further, Petitioner points out that
the challenged claims are directed to the mobile base station, and not to the
mobile unit, an element which is “merely ancillary” to what is claimed and
is not a “positively recited element.” Pet. Reply at 4–5.
Petitioner contends also that Patent Owner’s construction is
inconsistent with the intrinsic record. Pet. Reply 5–7. Petitioner argues that
the claims themselves do not require that the mobile device perform
registration or communicate directly with a cellular network. Pet. Reply 5–
6. Also, Petitioner argues that the specification of the ’904 patent discloses
that “the mobile unit does not receive communications from the fixed port
but only from the movable base station” and describes “eliminating any
direct communication from the mobile unit to the fixed radio port.” Pet.
Reply 6–7 (quoting Ex. 1001, 3:46–56) (citing Ex. 1001, 4:51–54). Finally,
Petitioner points to statements describing “mobile unit” made by the
applicant during the prosecution of the ’904 patent that contradict Patent
Owner’s narrow construction here. Pet. Reply 7 (citing Ex. 1002, 181).
Having reviewed and considered the record presented, including
Petitioner’s and Patent Owner’s submissions, we are not persuaded to adopt
Patent Owner’s construction of “mobile unit.” As instructed by Phillips, we
first look to the words of the claims. Phillips, 415 F.3d at 1312. We find
that the language of the challenged claims does not support Patent Owner’s
construction. As Petitioner points out, the challenged claims themselves are
not directed to the mobile unit. Pet. Reply 4–5. The challenged claims and
written description of the alleged invention in the ’904 patent focus on the
mobile base station, not the mobile units. Ex. 1030 (Reply Declaration of
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Dr. Zhi Ding) ¶¶ 12–13. This emphasis on the moving base station as the
invention is consistent with counsel for Patent Owner’s presentation at oral
argument: “The Carucel patents were the culmination of Mr. Gavrilovich’s
life’s work when he invented a moveable base station that significantly
improved wireless communications by acting as an intermediary between
cell towers and mobile devices.” Tr. 67:15–19. In addition, the claims
themselves do not specify a mobile device “that must register with and be
able to directly communicate with the cellular network.”
We find, for the reasons set forth below, that Patent Owner’s
contention that the mobile unit must be able to communicate directly with
the cellular network is not supported by the intrinsic record. In the
challenged claims, it is the mobile base station that communicates directly
with the fixed ports, not the mobile unit. Pet. Reply 5–6. As Petitioner
shows, we find that the challenged claims describe communications passing
between the moving base station (the “apparatus”) and the fixed port and
between the moving base station and the mobile unit. Pet. Reply 5–6; Ex.
1030 ¶ 14. Thus, claim 22 recites that the claimed apparatus (mobile base
station) has “a receiver adapted to receive a plurality of signals, each of the
plurality of signals transmitted from each of the plurality of fixed radio
ports” and “a transmitter adapted to transmit, within the frequency band, a
resultant signal to the mobile unit.” Claim 34 similarly recites that the
claimed apparatus (mobile base station) has “a first radio interface adapted
to communicate with the plurality of fixed radio ports” and “a second radio
interface adapted to communicate with the plurality of mobile units.”
Independent method claims 50 and 56 also reflect two different
communication paths – one between the fixed ports and the mobile station
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and the other between the mobile base station and the mobile unit. In
particular, claim 50 recites “receiving a plurality of signals at the movable
base station, each of the plurality of signals transmitted from each of the
plurality of fixed radio ports” and “transmitting, within the frequency band,
a resultant signal to the mobile unit in accordance with at least one of the
plurality of signals.” Similarly, claim 56 recites “establishing a first
communication link between the plurality of mobile units and a first fixed
port of the plurality of fixed ports through a movable base station”
(emphasis added). The challenged claims, therefore, do not require the
mobile device to communicate directly with a cellular network.
Furthermore, the challenged claims do not associate the signals
transmitted by the mobile unit to the movable base station with a cellular
network, or identify the recited mobile unit with a cellular network. As Dr.
Ding testifies: “[T]he claims only recite the mobile device as being able to
communicate with the claimed ‘apparatus’ or ‘movable base station’ by
receiving/transmitting general radio frequency ‘signals.’ The claims do not
provide any further limitations to the term ‘mobile device.’” Ex. 1030 ¶ 17.
Moreover, we find that the ’904 patent specification does not support
Patent Owner’s narrowing construction of “mobile unit” as a phone capable
of communications directly with a cellular network. Cf. PO Resp. 7–8. As
stated in Phillips, “the specification is always highly relevant to the claim
construction analysis. Usually, it is dispositive; it is the single best guide to
the meaning of a disputed term.” Phillips, 415 F.3d at 1315 (internal quotes
and citation omitted).
First, we do not see in the specification of the ’904 patent a clear
indication supporting Patent Owner’s contention that conventional cordless
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non-cellular phones should be excluded. Cf. PO Resp. 13 (“A mobile unit is
more than just a cordless phone handset.”). In the Background section, the
’904 patent describes the goal of the patent as encompassing “all
applications” including cordless phones: “What is desirable is an infra
structure which allows the use of such terminals in all applications, whether
in the home or office as a cordless phone . . . .” Ex. 1001, 2:44–46
(emphasis added). While the ’904 patent does refer to the base stations as
“cell site[s]” (Ex. 1001, 4:63–64), it also describes the radio interfaces
between the mobile devices and the base stations in more general terms.
Ex. 1001, 6:43–49. Thus, the ’904 patent describes the radio interfaces
between the mobile units and both the moving and fixed base stations as “a
standard radio interface, well known in the art.” Ex. 1001, 6:43–45. This
description is consistent with the stated goal of providing “an infra structure
which allows use of . . . a cordless phone.” Ex. 1001, 2:44–46.
Moreover, we find further support for our conclusion that Patent
Owner’s construction is too limiting in the ’904 patent’s description of an
embodiment where the mobile device is prevented from communicating
directly with the fixed ports. Pet. Reply 6–7 (citing Ex. 1001, 3:46–56). In
that embodiment, the power levels for the signals between the moving base
station and the mobile device are chosen to avoid direct communication
between the mobile device and the fixed radio ports. Ex. 1001, 3:43–56.
Phillips instructs us that the prosecution history may also be relevant
in construing the claims. 415 F.3d at 1317; see Pet. Reply 7 (discussing
prosecution history). During prosecution of the ’904 patent, in an appeal
brief to the Board, the applicant did not limit the invention to cellular
devices but told the Board that radios and telephones were included: “The
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present invention is directed to methods and devices for providing
communication services to moving mobile units such as telephones, radio
modems, or other types of radios.” Ex. 1002, 181 (emphasis added). We
find that this prosecution history describing the mobile units as “telephones”
and “radios” contradicts Patent Owner’s construction limiting such devices
to “a device that must register with and be able to directly communicate with
the cellular network.”
Patent Owner asserts that its proposed construction reflects “the plain
and ordinary meaning” of the term “mobile unit” under Phillips. PO
Resp. 13–16; PO Sur-reply 1–8. Patent Owner argues that Petitioner is
“construing the meaning of ‘mobile device’ in the abstract.” PO Sur-reply 1.
Patent Owner contends Petitioner’s analysis “is premised on incorrect legal
standards.” PO Sur-reply 2. Patent Owner argues that “the ’904 Patent
specification also describes the invention as a whole and should be limited
as such.” PO Sur-reply 2. Patent Owner continues: “Specifically, the ’904
Patent relates to and describes as a whole improving the wireless
connections of mobile devices within cellular telephone systems via a
moving base station . . . .” PO Sur-reply 2–3.
We are not persuaded by these arguments, as they are contrary to the
claim language and the intrinsic evidence discussed above. As explained
above, the challenged claims focus on the mobile base station, and Patent
Owner has asserted that the invention of the ’904 patent is the moving base
station, not the mobile units, which according to the prosecution history can
be conventional radios and telephones. See Hearing Tr. 67:15–19; see also
discussion above. While the ’904 patent may discuss cellular networks, we
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find that the disclosure does not limit the claimed “mobile unit” to cellular
phones, for the reasons given above.
Patent Owner does not explicitly argue that there has been a
disavowal or disclaimer of mobile units that do not communicate directly
with a cellular system either in the specification or prosecution history, and
there is no support for such an argument. As discussed above, the ’904
patent claims are directed to the mobile base station communicating with the
cellular network, and the specification describes an embodiment which
prevents the mobile unit from communicating with the fixed ports. “To
disavow claim scope, the specification must contain ‘expressions of manifest
exclusion or restriction, representing a clear disavowal of claim scope.’”
Retractable Techs., Inc. v. Becton, Dickinson & Co., 653 F.3d 1296, 1306
(Fed. Cir. 2011) (quoting Epistar v. Int’l Trade Comm’n, 566 F.3d 1321,
1335 (Fed. Cir. 2009)); SciMed Life Sys., Inc. v. Advanced Cardiovascular
Sys., Inc., 242 F.3d 1337, 1341 (Fed. Cir. 2001) (“Where the specification
makes clear that the invention does not include a particular feature, that
feature is deemed to be outside the reach of the claims of the patent, even
though the language of the claims, read without reference to the
specification, might be considered broad enough to encompass the feature in
question.”). The references to cellular communications in the ’904 patent
cited by Patent Owner (PO Sur-reply 5–6) are merely exemplary and do not
rise to the level of a clear and unmistakable disavowal.
Rather than asserting there has been a disavowal or disclaimer of
claim scope, Patent Owner argues “recent Federal Circuit precedent . . .
cautions against . . . effectively requiring statements in the intrinsic record to
rise to the level of a disclaimer in order to inform the meaning of the
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disputed claim term.” PO Sur-reply 4. We are not persuaded that Patent
Owner’s cited authorities support that argument here. PO Sur-reply 4–6.
In Pacing Technologies, LLC v. Garmin International, Inc., 778 F.3d
1021 (Fed. Cir. 2015), cited by Patent Owner, the Federal Circuit found
evidence of “a clear and unmistakable statement of disavowal or disclaimer”
in the stated objects of the invention, including a statement that the objects
would be accomplished by the particular feature (a “repetitive motion pacing
system”) to which the Court limited the claims. 778 F.3d at 1025. Here, in
contrast, for the reasons discussed above, there is no corresponding “clear
and unmistakable statement” limiting the scope of the mobile unit to “a
device that must register with and be able to directly communicate with the
cellular network.”
We do not find Patent Owner’s other authorities to be any more
persuasive. For example, in Personalized Media Communications, LLC v.
Apple Inc., 952 F.3d 1336 (Fed. Cir. 2020), (cited at PO Sur-reply 4), the
Federal Circuit relied on facts not present here, namely, that “[d]uring
prosecution, the applicant repeatedly and consistently voiced its position that
encryption and decryption require a digital process in the context of the ’091
patent.” 952 F.3d at 1345. Moreover, the Court observed: “The applicant
never abandoned that position. Indeed, the applicant amended the claims—
giving rise to the claim term at issue on appeal—only to clarify its position
that ‘encryption requires a digital signal.’” Id. at 1345–46. As discussed
above, the relevant prosecution history here does not include any such
repeated or consistent statements by Patent Owner excluding non-cellular
devices; in fact, the prosecution history includes a statement that radios and
telephones are within the scope of “mobile units.” Ex. 1002, 181. Nor has
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Patent Owner presented an amendment to the claims during prosecution that
would “clarify its position” that such devices are excluded.
Patent Owner cites Bell Atlantic Network Services, Inc. v. Covad
Communications Group, Inc., 262 F.3d 1258 (Fed. Cir. 2001), for the
proposition that the written description “can provide guidance as to the
meaning of the claims.” PO Sur-reply 4. This point is not is dispute. We
discuss the written description in our analysis above, and we find that it does
not support Patent Owner’s construction for the reasons given there. Bell
Atlantic does not help Patent Owner’s argument.
The same is true of Patent Owner’s discussion of On Demand
Machine Corp. v. Ingram Industries, Inc., 442 F.3d 1331 (Fed. Cir. 2006).
See PO Sur-reply 4–5. As Patent Owner’s quotation from On Demand
makes clear, it is not necessary to find an explicit disavowal “when the
scope of the invention is clearly stated in the specification, and is described
as the advantage and distinction of the invention.” 442 F.3d at 1340 (quoted
at PO Sur-reply 4). However, in our analysis above of Patent Owner’s
position, we find that the scope of the invention and its advantages as
described in the ’904 patent specification center on the mobile base station,
not the mobile device. The ’904 patent specification, therefore, does not
favor Patent Owner’s narrow construction of “mobile unit.” Thus, On
Demand’s exception to the normal requirement for an explicit disavowal is
not applicable here.
We are not persuaded by Patent Owner’s listing of “examples” from
the ’904 patent that discuss communications with the fixed base stations
when traveling at lower speeds of less than thirty miles per hour. PO Sur-
reply 3–4. Those citations do not describe the communications as cellular
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communications or fixed base stations 70 as cell sites, stating only that their
operation is “essentially the same as that of a standard fixed base station.”
Ex. 1001, 10:67–11:1.12 Nor are Patent Owner’s citations to the various
occurrences of the term “cellular” in the ’904 patent persuasive. Cf. PO Sur-
reply 5–6. There is no dispute that improving cellular technology is
included among the goals described in the ’904 patent. However, Patent
Owner fails to support its argument that the ’904 patent “explicitly and
exclusively relates to improving the wireless connections of mobile devices
within ‘cellular telephone systems.’” PO Sur-reply 5 (original emphasis
omitted; emphasis added). We find, based on the analysis above, that the
claims, the specification, and the prosecution history of the ’904 patent
reveal a broader goal of also improving wireless communications involving
non-cellular devices, such as radios and telephones.
Nor are we persuaded by Patent Owner’s suggestion that the
specification requires the mobile device to “register . . . with the cellular
network.” PO Resp. 13–14. Such a registration requirement is not in the
claims or prosecution history. Registration with a base station is mentioned
in the ’904 patent specification (see PO Resp. 14, PO Sur-reply 3), but the
registration process described there occurs only “[w]hen a mobile unit set is
first powered up or first enters a service area,” and involves the mobile
device transmitting its address to the moving base station, not the fixed base
stations. Ex. 1001, 9:64–10:2 (“The address will be received by the closest
moving base station 30 and transmitted . . . to the telephone network”). As

12 Patent Owner incorrectly quotes this passage as saying “a standard cellular
fixed base station.” PO Sur-reply 3–4 (quoting Ex. 1001, 10:67–11:15).
The word “cellular” does not appear in this passage of the ’904 patent.
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discussed above, such transmissions between the mobile unit and the moving
base station use a “standard radio interface.”
Thus, we find that Patent Owner’s analysis of the ’904 patent
specification does not support its theory that the mobile device
communicates directly with a cellular system when it registers during power
up or when first entering a service area. Further, we find that, to the extent
the ’904 patent discloses registration by the mobile device, it describes
registering with the moving base station and not with the fixed base station.
Ex. 1001, 9:64–10:4. The actual registration with the fixed base station is
handled by the mobile base station. Ex. 1001, 9:64–10:4.
In summary, we find that Patent Owner’s proposed construction for
“mobile unit” is not supported by the claim language of the ’904 patent or
the intrinsic evidence, and, therefore, we do not adopt a construction that
would limit “mobile unit” to cellular phones or other devices “that must
register with and be able to directly communicate with the cellular network”
and that would exclude conventional cordless phones.
We agree with Petitioner that no construction of “mobile unit” is
necessary. Pet. 14–15; Pet. Reply 4.
C. Principles of Law
A patent claim is unpatentable under 35 U.S.C. § 103(a) if the
differences between the claimed subject matter and the prior art are such that
the subject matter, as a whole, would have been obvious at the time the
invention was made to a person having ordinary skill in the art to which said
subject matter pertains. KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 406
(2007). The question of obviousness is resolved on the basis of underlying
factual determinations including (1) the scope and content of the prior art;
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(2) any differences between the claimed subject matter and the prior art;
(3) the level of ordinary skill in the art; and (4) any secondary
considerations, if in evidence.13 Graham v. John Deere Co., 383 U.S. 1,
17–18 (1966).
D. Obviousness over Gilhousen865 and Gilhousen390
(Claims 22, 23, 28–35, 40, 50, 51)
Petitioner asserts that claims 22, 23, 28–35, 40, 50, and 51 of the ’904
patent are unpatentable under 35 U.S.C. § 103(a) as obvious over the
combined teachings of Gilhousen865 and Gilhousen390. Pet. 5, 26–59.
1. Gilhousen865
Gilhousen865 is a patent titled “Airborne Radiotelephone
Communications System” and is directed to an airborne communication
system that allows radiotelephones on a plane to communicate with a
ground-based cellular system. Ex. 1005, codes (54), (57). Figure 1 of
Gilhousen865 is reproduced below.

13 Patent Owner does not present any objective evidence of nonobviousness
(i.e., secondary considerations) as to any of the challenged claims.
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Figure 1 of Gilhousen865, reproduced above, depicts an airborne
communication system having ground-based subsystem 105 and airborne-
based subsystem 125. Ex. 1005, 2:9–12. As shown in Figure 1, ground-
based subsystem 105 has base station 120 coupled to antenna 150 and to
mobile switching center 115, which in turn is coupled to public switched
telephone network (PSTN) 110. Ex. 1005, 2:21–33.
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Figure 2 of Gilhousen865 is reproduced below.

Figure 2 of Gilhousen865, reproduced above, depicts an airborne-based
subsystem having radiotelephones 205, signal repeater 210, and antenna 215
mounted on the outside of the aircraft. Ex. 1005, 2:45–52. Repeater 210
receives signals from radiotelephones 205 within the aircraft and relays them
to antenna 215, which relays the signals to the base station on the ground.
Ex. 1005, 2:53–57. Gilhousen865 discloses that signal repeater 210 may be
replaced by an airborne base station that “has the same functionality of its
ground-based counterpart but on a much smaller scale since it does not have
to handle the thousands of radiotelephones of the ground-based station.”
Ex. 1005, 3:3–10.
2. Gilhousen390
Gilhousen390 is a patent titled “Diversity Receiver in a CDMA
Cellular Telephone System” and discloses techniques for receiving the
strongest signals from multiple sites in a cellular system. Ex. 1006,
code (54), 4:27–34. One technique disclosed in Gilhousen390 involves
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using two receivers to demodulate signals on the two strongest paths and
using information from both signals in a “diversity combining operation,”
which results in improved resistance to multipath fading. Ex. 1006, 8:11–
21. Gilhousen390 also discloses a mobile unit having multiple digital data
receivers to enable diversity reception. Ex. 1006, 12:35–40, Fig. 2.
3. Independent Claim 22
a) Preamble
Claim 22 is directed to “[a]n apparatus adapted to move in accordance
with a movement of a mobile unit moving relative to a plurality of fixed
radio ports.” Petitioner contends that Gilhousen865’s disclosure of an
airborne base station (“apparatus”) on a plane that communicates with
radiotelephones (“mobile unit”) on the same plane teaches “[a]n apparatus
adapted to move in accordance with a movement of a mobile unit” because
the airborne base station and the telephones move together as the plane
moves. Pet. 32–33 (citing Ex. 1005, 2:46–52, 3:3–5, 3:7–10; Ex. 1003
¶ 115). As discussed above, Figure 2 of Gilhousen865 depicts the
airborne-based subsystem with radiotelephones 205 communicating with
signal repeater 210, and Gilhousen865 discloses that signal repeater 210 may
be replaced by an airborne base station. Ex. 1005, 2:46–49, 3:3–5.
Petitioner also contends that Gilhousen865’s disclosure of multiple
ground base stations teaches a plurality of fixed radio ports relative to which
the airborne base station and radiotelephones move. Pet. 33–34 (citing
Ex. 1005, 2:32–33, 3:53–62, 4:31–35; Ex. 1003 ¶¶ 118–119). We are
persuaded by this contention, and we find that Gilhousen865’s ground base
stations teach fixed radio ports. Gilhousen865 discloses that “signals from
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the ground base stations are received by the external antenna of the airborne
subsystem and repeated to the radiotelephones.” Ex. 1005, 3:55–57.
Patent Owner argues that Gilhousen865 does not teach two recitations
of the preamble—the “adapted to” language and the “mobile unit.”
i. Adapted to
Relying on the construction of “adapted to” as “constructed to move
with the traffic at a rate of speed which is comparable to the speed of the
traffic,” Patent Owner contends this preamble limitation is not met: “An
airplane does not move with traffic as it is not bound to predetermined
roads.” PO Resp. 44 (citing Ex. 2100 ¶¶ 174–175). Petitioner responds that
the term “traffic” should not be confined to “predetermined roads.” Pet.
Reply 11–12.
As discussed above in Section II.B.2, we apply the proposed
construction of “adapted to” as “constructed to move with the traffic at a rate
of speed which is comparable to the speed of the traffic.” However, we see
no proper basis in the language of the claims, the specification of the ’904
patent, or its prosecution history to further limit the claims to require
“predetermined roads.” The ’904 patent’s references to “pedestrian traffic”
(Ex. 1001, 2:39–42, 3:35–39, 4:48–51) further persuade us that Patent
Owner’s proposed narrowing of the term “traffic” as requiring
“predetermined roads” is contrary to the intrinsic record.
We are persuaded, and we find, that Gilhousen865’s disclosure of an
airborne base station in an airplane teaches an apparatus that is constructed
to move with the traffic at a rate of speed which is comparable to the speed
of the traffic, specifically air traffic. See Ex. 1003 ¶ 115 (“The airborne base
station also moves with airplane traffic at a rate of speed comparable to the
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speed of traffic, whether in the air or on the ground, because the base station
is moving with the airplane.”).
ii. Mobile unit
Referring back to its proposed claim construction, Patent Owner
contends that Gilhousen865 does not disclose “a radiotelephone that
registers with or is capable of directly communicating with the cellular
network as required by the limitation of a ‘mobile unit’ in the context of the
entire ’904 Patent.” PO Resp. 45–46; see also discussion at § II.B.3 above
(claim construction for “mobile unit”). Because we have not adopted Patent
Owner’s claim construction for “mobile unit,” we are not persuaded by this
argument. We find, instead, that Gilhousen865’s radiotelephone teaches a
“mobile unit.” See, e.g., Ex. 1005, 2:27–31 (discussing channels by which
the radiotelephone communicates with the base station), 2:32–33 (disclosing
that the base station receives signals from and radiates signals to the
radiotelephone); see also Pet. Reply 8 (citing Ex. 1005, 2:27–31, 2:37–41,
2:45–52, 3:38–40).
We also find, contrary to Patent Owner’s suggestion (PO Resp. 46),
that there is no additional requirement that the mobile unit must be “capable
of being switched back-and-forth between either a direct connection with the
fixed base station or a connection with a moving base station.” We see no
support for this additional requirement in the language of the claims, the
specification, or the prosecution history of the ’904 patent. Consequently,
we do not credit Patent Owner’s argument that Gilhousen865 does not have
this capability. PO Resp. 46.
Petitioner argues that, even under Patent Owner’s construction of
“mobile unit,” Gilhousen865 meets this limitation. Pet. Reply 9–11;
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Ex. 1030 ¶¶ 21–22. We agree with Petitioner and find that this limitation
would be met even if we had adopted Patent Owner’s construction for
“mobile unit.” Gilhousen865 explicitly teaches that the radiotelephones can
register with a base station in a cellular network. Ex. 1005, 3:57–59 (“This
enables the radiotelephones to search for the strongest pilot signal of the
next cell and register with that base station.”), cited in Pet. Reply 9.
Moreover, Gilhousen865 describes that the radiotelephones operate using
the industry standard for cellular networks. Ex. 1005, 2:65–3:2; Ex. 1030
¶ 23 (“Gilhousen865 discloses that the radiotelephone operates using the
Telecommunications Industries Association/Electronics Industries
Association Interim Standard 95 (TIA/EIA/IS-95). [Ex. ]1005, 2:65-3:2.
This standard was a well-known cellular telephone standard at the time that
has all the typical functionalities and services of a cellular telephone
network, including the capability for the radiotelephone to register with and
directly communicate with the cellular network.”). We find that such
phones would be capable of direct communication with the cellular network.
iii. Determination as to preamble
For the reasons discussed above, we find that Gilhousen865 teaches
the subject matter recited in the preamble (whether or not limiting) of
claim 22.
b) Receiver
Claim 22 recites that the apparatus has “a receiver adapted to receive a
plurality of signals, each of the plurality of signals transmitted from each of
the plurality of fixed radio ports within a frequency band having a lower
limit greater than 300 megahertz.” Petitioner contends that the combination
of Gilhousen865 and Gilhousen390 teaches this subject matter. Pet. 34–38.
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In particular, Petitioner contends Gilhousen865’s disclosure that the airborne
base station receives signals from base stations on the ground teaches a
receiver adapted to receive a plurality of signals. Pet. 34 (citing Ex. 1005,
3:52–59, 4:18–21; Ex. 1003 ¶¶ 121–125). For example, Gilhousen865
discloses that “signals from the ground base stations are received by the
external antenna of the airborne subsystem” and that “selector bank
subsystems (440) [of the airborne base station] are connected to the aircraft’s
external antenna (315) to receive and radiate the radiotelephone signals.”
Ex. 1005, 3:55–57, 4:18–21. Petitioner argues Gilhousen865 “does not
provide further details about its receivers” and relies on the teachings of
Gilhousen390. Pet. 34–38.
Citing Gilhousen390’s disclosure of a “receiver . . . which facilitates
reception and processing of the strongest signals transmitted from one or
more cell-sites, these signals being multipath signals from a single cell-site
or signals transmitted by multiple cell-sites” (Ex. 1006, 4:27–33), Petitioner
argues Gilhousen390 “discloses a receiver adapted to receive multiple
signals from each of multiple base stations.” Pet. 34–35 (citing Ex. 1006,
4:27–33). Petitioner also cites Gilhousen390’s disclosure in Figure 2 of
analog receiver 34 and digital data receivers 40 and 42 in one unit. Pet. 35–
36 (citing Ex. 1006, 8:61–63, 11:68–12:2, 12:26–30, 12:34–36, 12:63–66,
Fig. 2; Ex. 1003 ¶¶ 127, 129, 130). Referring to Figure 2, Gilhousen390
discloses that, “[i]f two receivers are provided, such as receivers 40 and 42,
then two independent paths can be tracked and in parallel.” Ex. 1006,
12:63–66. Petitioner also contends that Gilhousen390’s disclosure of
receiving signals “in the 850 MHz frequency band” (Ex. 1006, 12:2–6)
teaches “a frequency band having a lower limit greater than 300 megahertz,”
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as recited in claim 22. Pet. 38 (citing Ex. 1006, 11:68–12:6, 12:11–13;
Ex. 1003 ¶¶ 135–136).
Petitioner argues a person of ordinary skill in the art “would have
been motivated to employ similar receivers in Gilhousen865’s airborne base
station to track and process multiple signals from different base stations, for
example in the situation where the aircraft reaches the fringe of a particular
cell site.” Pet. 37 (citing Ex. 1003 ¶ 130). Petitioner provides additional
reasons to support its combination of the teachings of Gilhousen865 and
Gilhousen390, which we discuss below in § II.D.3.e. Pet. 26–31.
Patent Owner does not dispute that the combination of Gilhousen865
and Gilhousen390 teaches the “receiver” limitation of claim 22; rather,
Patent Owner argues that Petitioner has not shown sufficient reasoning to
combine the references. See PO Resp. 26–30, 33–37. We address the
parties’ contentions as to the rationale to combine below in § II.D.3.e.
Based on Petitioner’s persuasive contentions and the evidence
discussed above, we are persuaded, and we find, that the combination of
Gilhousen865 and Gilhousen390 teaches “a receiver adapted to receive a
plurality of signals, each of the plurality of signals transmitted from each of
the plurality of fixed radio ports within a frequency band having a lower
limit greater than 300 megahertz,” as recited in claim 22.
c) Transmitter
Claim 22 recites that the apparatus has “a transmitter adapted to
transmit, within the frequency band, a resultant signal to the mobile unit in
accordance with at least one of the plurality of signals.”
Petitioner contends that the combination of Gilhousen865 and
Gilhousen390 teaches “a transmitter adapted to transmit, within the
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frequency band, a resultant signal to the mobile unit in accordance with at
least one of the plurality of signals,” as recited in claim 22. Pet. 38–40.
Petitioner argues Gilhousen865’s disclosures of repeater 320 and
transceiver 410 in the airborne base station that communicate with
radiotelephones on the aircraft teaches a transmitter adapted to transmit a
resultant signal to the mobile unit. Pet. 38–39 (citing Ex. 1005, at code (57),
3:36–40, 4:6–8, Fig. 4; Ex. 1003 ¶ 138); see Ex. 1005, 3:36–40 (disclosing
that “aircraft repeater (320)” amplifies a received signal and “transmits the
amplifie[d] signal to the radiotelephone in the aircraft”), 4:6–8 (“[T]he
airborne base station is comprised of a number of base station transceivers
(410) that are the link between the radiotelephone and the base station.”).
Petitioner argues a person of ordinary skill in the art would have
understood that the signal transmitted from Gilhousen865’s airborne base
station to a radiotelephone inside the aircraft would have been within the
same frequency band as the received signal, citing Gilhousen390’s
disclosure of circuitry that converts signals to radio frequencies for
transmission and also citing the testimony of its declarant, Dr. Zhi Ding.
Pet. 39–40 (citing Ex. 1006, 11:68–12:6, 12:11–13, 14:16–26; Ex. 1003
¶¶ 139–140).
Patent Owner argues that Gilhousen390 discloses a cell site, i.e., a
fixed radio port, transmitting signals to a mobile unit rather than a moving
base station transmitting a resultant signal to a mobile unit. PO Resp. 47–
49; PO Sur-reply 20–21. Petitioner, however, relies on Gilhousen865, not
Gilhousen390, to teach a moving base station. Pet. 38–40; Pet. Reply 14.
Petitioner relies on Gilhousen 390 for the “within the frequency band”
language of the “transmitter” limitation. Pet. 39–40. In particular, Petitioner
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asserts that, “[a]lthough a [person of ordinary skill in the art] would have
understood that the signal transmitted to the radiotelephone would typically
be transmitted within the same frequency band as the received signal, this is
not explicitly stated by Gilhousen865,” and Petitioner relies on
Gilhousen390’s disclosures of transmitting signals to mobile units to show
transmitting a resultant signal “within the frequency band,” as recited in
claim 22. Pet. 39–40. Thus, Patent Owner’s argument that Gilhousen390
does not teach a moving base station is not persuasive because it is not
responsive to Petitioner’s contentions.
Based on Petitioner’s persuasive contentions and the evidence
discussed above, we are persuaded, and we find, that the combination of
Gilhousen865 and Gilhousen390 teaches “a transmitter adapted to transmit,
within the frequency band, a resultant signal to the mobile unit in accordance
with at least one of the plurality of signals,” as recited in claim 22.
d) Processor
Petitioner also contends that the combination of Gilhousen865 and
Gilhousen390 teaches “a processor adapted to maximize an amount of
transferred information to the mobile unit by evaluating a quality of each of
the plurality of signals transmitted from the plurality of fixed radio ports,” as
recited in claim 22. Pet. 40–45. Petitioner notes that Gilhousen865
discloses that its airborne base station has call control processor 420 and
selector bank subsystems 440. Pet. 40–41 (citing Ex. 1005, 4:11–13, 4:17–
19, Fig. 4). Gilhousen865 discloses that “call control processor (420)
controls signaling with the radiotelephones, controls all call processing, and
allocates the base station resources” and that “selector bank subsystems
(440) process[] and format[] the data between the ground base stations and
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the radiotelephone.” Ex. 1005, 4:11–13, 4:16–18. Petitioner cites various
disclosures of Gilhousen390 to teach devices that are “adapted to maximize
an amount of transferred information to the mobile unit by evaluating a
quality of each of the plurality of signals transmitted from the plurality of
fixed radio ports,” as recited in claim 22. Pet. 41–44. One disclosure from
Gilhousen390 cited by Petitioner is the following:
In the cell-site diversity mode, the strongest paths from
each cell-site is determined by the search receiver. The two
receivers are assigned to demodulate the signals on the strongest
two paths of the paths available from the original cell-site and
from the new cell-site. The data demodulation process uses
information from both of these receivers in a diversity combining
operation. The result of this diversity combining operation is a
greatly improved resistance to deleterious fading that may occur
in the multipath cellular telephone environment.
Ex. 1006, 8:11–21, quoted in Pet. 43. Petitioner contends that, “[b]ecause
fading is likely to occur at different times among different signals,”
Gilhousen390’s diversity combining operation would maximize the amount
of data transferred to a mobile unit in the system of Gilhousen865. Pet. 44
(citing Ex. 1003 ¶¶ 151–152). Petitioner contends that a person of ordinary
skill in the art “would have been motivated to implement the cell-site
diversity mode of Gilhousen390 at the airborne base station of Gilhousen865
to optimize the signal transmitted from the base station to the
radiotelephone.” Pet. 44 (citing Ex. 1003 ¶ 152).
Patent Owner does not dispute that the combination of Gilhousen865
and Gilhousen390 teaches the “processor” limitation of claim 22; rather,
Patent Owner argues that Petitioner has not shown sufficient reasoning to
combine the references. See PO Resp. 26–30, 33–37. We address the
parties’ contentions as to the rationale to combine below in § II.D.3.e.
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Based on Petitioner’s persuasive contentions and the evidence
discussed above, we are persuaded, and we find, that the combination of
Gilhousen865 and Gilhousen390 teaches “a processor adapted to maximize
an amount of transferred information to the mobile unit by evaluating a
quality of each of the plurality of signals transmitted from the plurality of
fixed radio ports,” as recited in claim 22.
e) Rationale for combining Gilhousen865 and Gilhousen390
Petitioner provides a rationale for combining Gilhousen865 and
Gilhousen390. Pet. 26–31. Relying on testimony from Dr. Ding, Petitioner
argues that “[d]eleterious effects on wirelessly-transmitted signals, such as
fading, interference, and other degradations to signal quality were
well-known at the time of the ’904 patent.” Pet. 28 (citing Ex. 1003 ¶¶ 97–
98). Petitioner argues that a person of ordinary skill “would have been
motivated to look to the prior art, such as Gilhousen390, for techniques of
reducing the negative effects on signals during wireless transmission.”
Pet. 28. Petitioner contends: “In order to counter the negative effects of
fading, Gilhousen390 describes employing various configurations to achieve
signal diversity at the receiver.” Pet. 29 (citing Ex. 1003 ¶¶ 98–107).
Petitioner identifies one such configuration in Gilhousen390 as cell-site
diversity, in which a receiver simultaneously receives a signal from two cell
sites. Pet. 29 (citing Ex. 1006, 11:58–62). Petitioner asserts the following:
Based on the teachings of Gilhousen390, a [person of
ordinary skill in the art] would have been motivated to modify
Gilhousen865’s system with any one or more of the signal
diversity configurations of Gilhousen390 at least for the purpose
of reducing errors caused by well-known deleterious effects on
wirelessly-transmitted signals.
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Pet. 30 (citing Ex. 1003 ¶¶ 108–109). Petitioner argues that
“Gilhousen865’s airborne base station could be modified with one or more
data receivers that are individually configurable to extract multiple signals
received from the same or different base stations, as taught by
Gilhousen390” and that “modifying Gilhousen865 in this manner would
have required minimal modifications.” Pet. 30 (citing Ex. 1003 ¶¶ 108–
109).
Patent Owner makes several arguments challenging Petitioner’s
motivation to combine Gilhousen865 and Gilhousen390 and challenging
Petitioner’s assertion of a reasonable expectation of success. PO Resp. 26–
37. Patent Owner argues the following:
Gilhousen390’s CDMA signal diversity configurations will not
work if employed on Gilhousen865’s high speed airborne
repeater, because Gilhousen390’s CDMA signal diversity
configuration cannot increase the power of Gilhousen865’s
airborne repeater fast enough to compensate for the transmitted
signal fading that is occurring on the connection with the base
station due to the high speed of Gilhousen865’s airborne
repeater.
PO Resp. 34 (citing Ex. 2100 ¶¶ 148–151); see also PO Resp. 36 (discussing
speed of a commercial jet). According to Patent Owner, “any calls in
progress will be dropped because handovers cannot occur” in Petitioner’s
proposed combination. PO Resp. 34 (citing Ex. 2100 ¶¶ 148–151).
Petitioner responds that “Gilhousen865’s communication system is a
CDMA communication system” and, consequently, the system “would have
considered the power control and other features of CDMA systems to
operate in its preferred embodiment––on a plane.” Pet. Reply 28–29.
Petitioner also responds that Patent Owner’s presumed rate of speed for an
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aircraft is “exaggerated,” using the Cessna 152 airplane as an example.
Pet. Reply 29 (citing Ex. 1037, “Cessna 152 Information Manual”).
We do not need to reach the question of whether the proposed
combination would work on the Cessna 152 (which Patent Owner contends
went out of production in 1985). See PO Sur-reply 9. The flaw in Patent
Owner’s argument is that Patent Owner assumes that the person of ordinary
skill (a highly trained and experienced wireless communications systems
engineer) would not be able to resolve the technical issues hypothesized by
Patent Owner’s expert, Mr. Lanning. As the Federal Circuit has
emphasized, in analyzing obviousness, KSR assumes that the person of
ordinary skill “is not an automaton”:
KSR does not require that a combination only unite old elements
without changing their respective functions. Instead, KSR
teaches that “[a] person of ordinary skill is also a person of
ordinary creativity, not an automaton.” And it explains that the
ordinary artisan recognizes “that familiar items may have
obvious uses beyond their primary purposes, and in many cases
a person of ordinary skill will be able to fit the teachings of
multiple patents together like pieces of a puzzle.”
ClassCo, Inc. v. Apple, Inc., 838 F.3d 1214, 1219 (Fed. Cir. 2016) (citations
omitted). The Federal Circuit further cautioned in ClassCo that “the
rationale of KSR does not support [the] theory that a person of ordinary skill
can only perform combinations of a puzzle element A with a perfectly fitting
puzzle element B.” Id. Thus, we find that Mr. Lanning’s testimony on this
issue is out of step with the Supreme Court’s admonition in KSR that the
person of ordinary skill in not “an automaton.” KSR, 550 U.S. at 421.
Rather, we credit Dr. Ding’s testimony that a person of ordinary skill
would have been motivated to combine the teachings of Gilhousen865 and
Gilhousen890 with a reasonable expectation of success. See Ex. 1003
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¶¶ 96–109; Ex. 1030 ¶¶ 46–50. In particular, Dr. Ding testifies that a person
of ordinary skill in the art “would have understood that Gilhousen865’s
CDMA communication system would have considered the power control
and other features of CDMA systems to operate in its preferred
environment—on a plane.” Ex. 1030 ¶ 46. We find this testimony credible
because Gilhousen865 discloses a CDMA communication system.
Ex. 1005, 2:13–15 (discussing ground-based CDMA system), 2:46–52
(discussing airborne-based CDMA system). Furthermore, Dr. Ding explains
that Gilhousen865’s disclosure does not indicate that there would have been
any compatibility issues incorporating ground-based technology: “If the
inventor of Gilhousen865 had expected compatibility issues employing
communication systems developed for ground vehicles in an airplane, the
inventor would not have cited and incorporated teachings from Tiedemann,”
“which discloses a ‘vehicle mounted unit’ for use with ground vehicles
traveling on a roadway.” Ex. 1030 ¶ 50 (citing Ex. 2113,14 1:17–20, 3:31–
46). We credit this testimony because Tiedemann is directed to cellular
telephone registration in the context of vehicles traveling on a road
(“freeway”) (Ex. 2113, 3:31–46), and Gilhousen865 refers to Tiedemann for
details on mobile unit “registration” and “hand-off” (Ex. 1005, 3:22–24,
3:53–55). Thus, we agree with Dr. Ding that “Gilhousen865 recognized the
applicability and compatibility of such [ground-based] communication
systems with airborne communications.” Ex. 1030 ¶ 50.

14 Although Dr. Ding identifies “Tiedemann” as U.S. Patent No. 5,621,784,
Exhibit 2113, which Dr. Ding cites, is U.S. Patent No. 5,289,527, and this is
the patent referenced in Gouhousen865. See Ex. 1005, 3:22–24.
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Patent Owner also argues that Petitioner’s rationale for combining
Gilhousen865 and Gilhousen390 and the supporting testimony from Dr.
Ding are “conclusory.” PO Resp. 26–27 (asserting the Petition merely
contains “conclusory assurances that a person of ordinary skill could
combine Petitioner’s prior art references, but the Petition never actually
articulates how the [person of ordinary skill in the art] could do so”). We
disagree and credit Dr. Ding’s testimony. See Ex. 1003 ¶¶ 96–109; Ex. 1030
¶¶ 46–50. As previously discussed, we find that Petitioner’s explanation of
the rationale for combining the teachings of the cited references and Dr.
Ding’s testimony are supported by the record and are not conclusory.
Patent Owner further argues that the Petition does not supply
“sufficient detail how to combine” Gilhousen865 and Gilhousen390, or
sufficiently demonstrate “a reasonable expectation of success.” PO
Resp. 26–31. We find that Petitioner provides a sufficiently detailed
explanation of how the references could have been combined. See Pet. 26–
31, 34–45. According to the ’904 patent, the invention uses “well-known”
equipment and functions. See, e.g., Ex. 1001, 4:28–29, 5:5–6, 5:23, 5:50,
5:62, 6:15, 6:25–27, 6:41–42, 6:45, 6:54–55, 9:17–20, 9:33, 9:63. We find
Mr. Lanning’s testimony raising various technical problems in combining
the references to be inconsistent with the admonition by the Federal Circuit
that “the rationale of KSR does not support [the] theory that a person of
ordinary skill can only perform combinations of a puzzle element A with a
perfectly fitting puzzle element B.” ClassCo, Inc., 838 F.3d at 1219. In
contrast, Dr. Ding credibly testifies as to how a person of ordinary skill in
the art “could have combined” Gilhousen865 and Gilhousen390. Ex. 1003
¶¶ 96–109; see Ex. 1003 ¶ 109 (“[T]he proposed combination of
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Gilhousen865 and Gilhousen390 would involve nothing more than
incorporating well-known concepts (i.e., Gilhousen390’s diversity
techniques) into a well-known system (i.e., Gilhousen865’s radio
communication system).”). We are not persuaded that more detailed
explanations of how to combine such “well-known” equipment are required
by KSR. As the Federal Circuit stated in Rothman v. Target Corp., 556 F.3d
1310, 1319 (Fed. Cir. 2009): “[T]his invention falls into a very predictable
field. In the predictable arts, a trial record may more readily show a
motivation to combine known elements to yield a predictable result, thus
rendering a claimed invention obvious.”
Furthermore, Patent Owner’s assertion that “Gilhousen865 lacks the
necessary design and circuitry details for the airborne repeater to even to be
utilized by a [person of ordinary skill in the art] as a primary reference” (PO
Resp. 36) fails to appreciate that the high level of skill in the art (see § II.A
above), which is also reflected in the ’904 patent’s use of “well-known”
equipment and functions, the details of which the ’904 patent does not
describe. C.f. In re Epstein, 32 F.3d 1559, 1568 (Fed. Cir. 1994) (comparing
level of details provided in the specification and the cited prior art in the
context of whether a prior art reference is enabling).
We find that Petitioner has demonstrated by a preponderance of the
evidence that a person of ordinary skill would have combined Gilhousen890
and Gilhousen865 with a reasonable expectation of success.
f) Determination of unpatentability
For the reasons discussed above, we find that the combination of
Gilhousen865 and Gilhousen390 teaches the subject matter recited in
claim 22 and that a person of ordinary skill in the art would have been
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motivated to combine the teachings of these references in the manner
asserted with a reasonable expectation of success. Based on the full trial
record, we conclude that Petitioner has demonstrated that the subject matter
recited in claim 22 would have been obvious over the combined teachings of
Gilhousen865 and Gilhousen390.
4. Independent Claim 34
a) Preamble
Claim 34 is directed to “[a]n apparatus adapted to move in accordance
with a movement of a plurality of mobile units moving relative to a plurality
of fixed radio ports at a velocity greater than a relative velocity of movement
between each of the mobile units of the plurality of mobile units” (emphasis
added). The italicized subject matter does not appear in the preamble of
claim 22.
For the preamble of claim 34, Petitioner refers to its contentions for
the preamble of claim 22. Pet. 52. Petitioner also argues that “the airborne
base station of Gilhousen865 moves ‘at a velocity greater than a relative
velocity of movement between each of the mobile units of the plurality of
mobile units’ because the radiotelephones on the aircraft and the airborne
base station move at approximately the same speed.” Pet. 52 (citing
Ex. 1003 ¶ 181).
Patent Owner argues that Petitioner has not shown that Gilhousen865
teaches the “adapted to” subject matter for the same reasons it advances for
claim 22. PO Resp. 55–56. For the reasons explained above in § II.D.3.a.i
(discussing “adapted to” in preamble of claim 22), we disagree with Patent
Owner and find that Gilhousen865 teaches this subject matter.
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Patent Owner also argues that Petitioner has not shown that
Gilhousen865 teaches “mobile units” for the same reasons it advances for
claim 22. PO Resp. 61–62. For the reasons explained above in § II.D.3.a.ii
(discussing “mobile unit” in preamble of claim 22), we disagree with Patent
Owner’s arguments. Claim 34 recites “a plurality of mobile units,” and we
are persuaded, and we find, that Gilhousen865 teaches the recited “plurality”
because it discloses multiple radiotelephones in the aircraft. Ex. 1005, 2:57–
59 (“This subsystem may have a single radiotelephone, as in a small aircraft,
or multiple radiotelephones, as in an airline size aircraft.”), Fig. 2.
For the reasons discussed here and in § II.D.3.a, we find that
Gilhousen865 teaches the subject matter recited in the preamble (whether or
not limiting) of claim 34.
b) First radio interface
Claim 34 recites that the apparatus has “a first radio interface adapted
to communicate with the plurality of fixed radio ports in a frequency band.”
Petitioner argues that the combination of Gilhousen865 and Gilhousen390
teaches this subject matter, referring to its contentions for the “receiver”
subject matter recited in claim 22. Pet. 53 (citing Ex. 1005, 3:55–57, 4:18–
21; Ex. 1003 ¶ 183). Patent Owner does not dispute Petitioner’s contentions
for this limitation. See PO Resp. 55–62.
We are persuaded by Petitioner’s contentions. In particular,
Gilhousen865 discloses that “signals from the ground base stations are
received by the external antenna of the airborne subsystem” and that
“selector bank subsystems (440) [of the airborne base station] are connected
to the aircraft’s external antenna (315) to receive and radiate the
radiotelephone signals.” Ex. 1005, 3:55–57, 4:18–21. Thus, we find that the
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combination of Gilhousen865 and Gilhousen390 teaches “a first radio
interface adapted to communicate with the plurality of fixed radio ports in a
frequency band,” as recited in claim 34.
c) Second radio interface
Claim 34 recites that the apparatus has “a second radio interface
adapted to communicate with the plurality of mobile units in the frequency
bandwidth, the frequency having a lower limit greater than 300 megahertz.”
Petitioner argues that the combination of Gilhousen865 and Gilhousen390
teaches this subject matter, referring to its contentions for the “receiver” and
“transmitter” limitations recited in claim 22. Pet. 53 (citing Ex. 1005, 4:6–8;
Ex. 1003 ¶¶ 185–186).
Patent Owner makes the same argument here that it makes for the
“transmitter” limitation of claim 22—that Gilhousen390 discloses a cell site,
i.e., a fixed radio port, transmitting signals to a mobile unit rather than a
moving base station transmitting a signal to a mobile unit. PO Resp. 56–58.
As discussed above in § II.D.3.c, Petitioner relies on Gilhousen865, not
Gilhousen390, to teach a moving base station. See, e.g., Ex. 1005, 4:6–8
(“[T]he airborne base station is comprised of a number of base station
transceivers (410) that are the link between the radiotelephone and the base
station.”), quoted in part in Pet. 53. Therefore, Patent Owner’s argument is
not responsive to Petitioner’s contentions.
For the reasons discussed above in § II.D.3.c for the “transmitter”
limitation of claim 22, we are persuaded, and we find, that the combination
of Gilhousen865 and Gilhousen390 teaches “a second radio interface
adapted to communicate with the plurality of mobile units in the frequency
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bandwidth, the frequency having a lower limit greater than 300 megahertz,”
as recited in claim 34.
d) Processor
Claim 34 recites that the apparatus has
a processor adapted to establish a communication link between
the plurality of mobile units and at least one of the plurality of
fixed radio ports based on a plurality of signal quality indicators,
each of the signal quality indicators corresponding to each of a
plurality of transmitted signals transmitted from the plurality of
fixed radio ports.
Petitioner refers to its contentions for the “processor” limitation of
claim 22 and provides additional explanation to address the subject matter
recited here. Pet. 54–55. As discussed above in § II.D.3.d, Petitioner
identifies Gilhousen865’s call control processor 420 and selector bank
subsystems 440 as the claimed “processor.” Pet. 40–41 (citing Ex. 1005,
4:11–13, 4:17–19, Fig. 4). Petitioner argues that Gilhousen865’s Figures 1
and 2 show establishing “a communication link between the plurality of
mobile units and at least one of the plurality of fixed radio ports.” Pet. 54
(citing Ex. 1005, Figs. 1, 2; Ex. 1003 ¶ 188).
Petitioner argues that Gilhousen390’s disclosure of measuring and
comparing the strength of received signals teaches “a plurality of signal
quality indicators,” and Petitioner contends that a person of ordinary skill in
the art would “have understood that the ‘communication link’ is based on
these signal quality indicators because the fixed base station(s) that form the
communication link are dictated by the strength of the signals received by
the airborne base station.” Pet. 54–55 (citing Ex. 1006, 12:67–13:9;
Ex. 1003 ¶¶ 189–192).
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Patent Owner argues that Gilhousen390’s control processor is in a
mobile unit, not in a mobile base station, i.e., the claimed “apparatus.” PO
Resp. 58–60. We agree with Patent Owner on this point, but Petitioner
relies on Gilhousen865’s call control processor 420 and selector bank
subsystems 440 to teach the claimed “processor.” Pet. 40–41, 54. Petitioner
relies on Gilhousen390 for particular teachings of measuring signal strength
to teach “signal quality indicators.” Pet. 54–55. Thus, Patent Owner’s
argument that Gilhousen390 does not teach a processor in a moving base
station is not persuasive because it is not responsive to Petitioner’s
contentions.
Patent Owner also argues, without explanation, that “Gilhousen865
does not disclose or imply any processor adapted ‘to establish a
communication link between the plurality of mobile units and at least one of
the plurality of fixed radio ports.’” PO Resp. 61. We disagree because
Gilhousen865 discloses that “call control processor (420) controls signaling
with the radiotelephones, controls all call processing, and allocates the base
station resources” and that “selector bank subsystems (440) process[] and
format[] the data between the ground base stations and the radiotelephone.”
Ex. 1005, 4:11–13, 4:16–18. Thus, Gilhousen865 discloses that call control
processor 420 and selector bank subsystems 440, which are both in the
airborne base station, establish a communication link between the phones on
the plane and the ground base stations.
Emphasizing the “plurality of fixed radio ports” language of claim 34,
Patent Owner further argues that “Gilhousen865 only discloses a
communication link between a plurality of mobile units and a single fixed
radio port.” PO Sur-reply 26. This argument is unavailing for two reasons.
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First, claim 34 recites “a processor adapted to establish a communication
link between the plurality of mobile units and at least one of the plurality of
fixed radio ports” (emphasis added). Thus, a communication link between
multiple phones on the plane and a single fixed radio port meets the claim
limitation. Second, Gilhousen865 discloses communications with multiple
ground base stations: “[S]elector bank subsystems (440) processes and
formats the data between the ground base stations and the radiotelephone.”
Ex. 1005, 4:16–18.
For the reasons discussed above, we are persuaded, and we find, that
Gilhousen865 teaches a moving base station, i.e., the claimed “apparatus”
that has “a processor adapted to establish a communication link between the
plurality of mobile units and at least one of the plurality of fixed radio
ports.” We are persuaded by Petitioner’s contentions that Gilhousen390’s
disclosure of measuring and comparing signal strengths teaches “signal
quality indicators” and that the communication link is chosen based on the
signal strengths. See Pet. 54–55 (citing Ex. 1003 ¶¶ 189–192; Ex. 1006,
12:67–13:9 (“Receiver 44 will measure the strength of any reception of a
desired waveform at times other than the nominal time. Receiver 44
compares signal strength in the received signals. Receiver 44 provides a
signal strength signal to control processor 46 indicative of the strongest
signals and relative time relationship.”)).
Based on Petitioner’s persuasive contentions and the evidence
discussed above, we are persuaded, and we find, that the combination of
Gilhousen865 and Gilhousen390 teaches
a processor adapted to establish a communication link between
the plurality of mobile units and at least one of the plurality of
fixed radio ports based on a plurality of signal quality indicators,
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each of the signal quality indicators corresponding to each of a
plurality of transmitted signals transmitted from the plurality of
fixed radio ports,
as recited in claim 34.
e) Determination of unpatentability
For the reasons discussed above in this section and in § II.D.3
(addressing claim 22), based on the full trial record, we conclude that
Petitioner has demonstrated that the subject matter recited in claim 34 would
have been obvious over the combined teachings of Gilhousen865 and
Gilhousen390.
5. Independent Claim 50
Independent claim 50 is a method claim that recites subject matter
similar to claim 22. For example, the preamble of claim 50 recites “[a]
method of providing a communication link between a communication
network and a mobile unit having a motion relative to a plurality of fixed
ports, wherein the plurality of fixed ports are communicatively coupled to
the communication network.” Petitioner refers to its contentions for the
preamble of claim 22 and additionally explains how Gilhousen865’s
airborne phone system teaches a “communication network” that is
“communicatively coupled” to ground base stations 120 (“fixed ports”). Pet.
57–58 (citing Ex. 1005, 2:9–10, Figs. 1, 2; Ex. 1003 ¶¶ 202–203).
Claim 50 recites “moving a movable base station in accordance with
the motion of the mobile unit.” Petitioner refers to its contentions for the
preamble of claim 22, which recites “[a]n apparatus adapted to move in
accordance with a movement of a mobile unit moving relative to a plurality
of fixed radio ports.” Pet. 58.
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For the limitation reciting “receiving a plurality of signals at the
movable base station, each of the plurality of signals transmitted from each
of the plurality of fixed radio ports within a frequency band having a lower
limit greater than 300 megahertz,” Petitioner refers to its contentions for the
“receiver” limitation of claim 22, which recites substantially similar subject
matter. Pet. 58.
For the limitation reciting “transmitting, within the frequency band, a
resultant signal to the mobile unit in accordance with at least one of the
plurality of signals,” Petitioner refers to its contentions for the “transmitter”
limitation of claim 22, which recites substantially similar subject matter.
Pet. 58.
For the limitation reciting “maximizing an amount of transferred
information to the mobile unit by evaluating a quality of each of the plurality
of signals transmitted from the plurality of fixed radio ports,” Petitioner
refers to its contentions for the “processor” limitation of claim 22, which
recites substantially similar subject matter. Pet. 59.
Patent Owner relies on the same arguments addressed above in the
context of claim 22, including that the combination of Gilhousen865 and
Gilhousen390 does not teach the claimed “mobile unit.” See generally PO
Resp. 26–32, 33–37, 43–49, 64. For the reasons explained above in § II.D.3
discussing claim 22, we disagree with Patent Owner’s arguments.
For the reasons discussed above in this section and in § II.D.3, based
on the full trial record, we conclude that Petitioner has demonstrated that the
subject matter of claim 50 would have been obvious over the combined
teachings of Gilhousen865 and Gilhousen390.
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6. Dependent Claims 23, 35, and 51
Dependent claims 23, 35, and 51 depend, respectively, from
independent claims 22, 34, and 50 and recite that “the frequency band has a
lower limit of 300 megahertz.” Petitioner argues that “using a lower limit of
300 megahertz would have been nothing more than a simple design choice,”
and Petitioner cites Gilhousen390’s disclosure of UHF, which Petitioner
argues a person of ordinary skill in the art would have understood has a
lower limit of 300 MHz. Pet. 45–46 (citing Ex. 1003 ¶¶ 154–155; Ex. 1006,
3:6–10; Ex. 1009, 21; Ex. 1010, 27).
Patent Owner does not dispute Petitioner’s contentions as to these
claims. See generally PO Resp. We are persuaded by Petitioner’s
contentions and evidence, and we conclude that the subject matter recited in
claims 23, 35, and 51 would have been obvious based on the combination of
Gilhousen865 and Gilhousen390.15
7. Dependent Claim 28
Claim 28 recites, “An apparatus in accordance with claim 22, wherein
the processor is further adapted to determine a best fixed radio port of the
plurality of fixed radio ports, the best fixed radio port enabling the
maximization of the amount of transferred information to the mobile unit.”
Petitioner argues that Gilhousen865’s disclosure of searching for the

15 Petitioner correctly points out that claim 23’s recitation of a lower limit of
300 MHz contradicts claim 22’s requirement of a lower limit greater than
300 MHz. See Pet. 45. The same issue applies for claims 35 and 51. This
issue does not impact our ultimate conclusion of obviousness because
Petitioner has shown that a lower limit of 300 MHz and a lower limit greater
than 300 MHz both would have been obvious to a person of ordinary skill in
the art.
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strongest pilot signal and registering with that base station teaches
“determin[ing] a best fixed radio port of the plurality of fixed radio ports.”
Pet. 46 (citing Ex. 1005, 4:1–5; Ex. 1003 ¶ 157). Petitioner also asserts that
claim 28’s recitation of “enabling the maximization of the amount of
transferred information to the mobile unit” is met for the same reasons given
for claim 22’s recitation of “maximiz[ing] an amount of transferred
information to the mobile unit.” Pet. 46.
Patent Owner argues that “the ’904 Patent provides that
‘determin[ing] a best fixed radio port’ is more than just analyzing the
strongest signal.” PO Resp. 52 (citing Ex. 1001, 11:7–12). According to
Patent Owner, “[a]t a minimum, ‘determin[ing] a best fixed radio port’
includes an analysis of the signal quality (i.e., error rate) in addition to the
signal strength when viewed in the entire context of the ’904 Patent.” PO
Resp. 52 (citing Ex. 2100 ¶ 192).
Petitioner responds that “the passage of the ’904 patent cited by
[Patent Owner] does not even relate to the functionality of the moving base
station; rather, this passage relates to handoff decision-making at the mobile
device.” Pet. Reply 16 (citing Ex. 1001, 11:7–18; Ex. 1030 ¶ 35). We agree
with Petitioner. The passage relied on by Patent Owner describes the mobile
unit’s operation in monitoring the signal from the base stations: “Each
mobile unit monitors pilot signals from fixed and moving base stations and
synchronizes to the base station providing the best signal.” Ex. 1001, 10:65–
67. The claim, however, is directed to functionality of a processor in the
moving base station. Nor does the claim specify particular metrics (such as
error rate) that must be evaluated by the claimed apparatus to select a “best
fixed radio port.”
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Patent Owner’s declarant, Mr. Lanning, testifies that
the strongest signal may not be the best fixed radio port . . .
because the strongest received pilot signal may not be coming
from the correct cellular network operator or the strongest pilot
signal may have some type of distortion that would cause errors
in the physical level signal being received.
Ex. 2100 ¶ 192. But this analysis ignores Petitioner’s contentions for the
remainder of claim 28, which recites “the best fixed radio port enabling the
maximization of the amount of transferred information to the mobile unit.”
For this subject matter, Petitioner refers to its contentions for claim 22’s
recitation of “a processor adapted to maximize an amount of transferred
information to the mobile unit.” Pet. 46; Pet. Reply 15. As discussed above
in § II.D.3.d, we are persuaded, and we find, that the combination of
Gilhousen865 and Gilhousen390 teaches “a processor adapted to maximize
an amount of transferred information to the mobile unit,” as recited in
claim 22. Thus, Petitioner’s contentions for claim 28 are in the context of
maximizing the amount of transferred information. A signal from the wrong
cellular network operator, for example, likely would result in little, if any,
data being transferred.
For the reasons set forth in the Petition and those explained above in
this section and in § II.D.3.d (addressing the “processor” limitation of
claim 22), we are persuaded that the subject matter recited in claim 28 would
have been obvious based on the combination of Gilhousen865 and
Gilhousen390.
8. Dependent Claims 29–31
Claim 29 depends from claim 28 and recites that “the transmitter is
further adapted to transmit the resultant signal in accordance with the signal
transmitted from the best fixed radio port.” Petitioner argues that this
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subject matter is met by referring to its contentions for the “transmitter” and
“processor” limitations of claim 22 and citing Gilhousen865’s disclosure of
transmitting a signal from the airborne repeater to the phone on the aircraft.
Pet. 47 (citing Ex. 1005, 3:36–40; Ex. 1003 ¶¶ 159–160).
Claim 30 depends from claim 29 and recites that “the processor is
further adapted to determine a plurality of best fixed radio ports and to
combine a group of signals of the plurality of signals to produce the resultant
signal, the group of signals transmitted from the plurality of best fixed radio
ports.” Petitioner argues that this subject matter is met by referring to its
contentions for the “processor” limitation of claim 22 and citing
Gilhousen390’s disclosure of tracking signals from multiple base stations
and combining those signals. Pet. 47–48 (citing Ex. 1006, 12:63–66, 13:7–
9, 13:22–32; Ex. 1003 ¶¶ 162–164).
Claim 31 depends from claim 30 and recites that “the processor is
further adapted to combine the group of signals by synchronizing the group
of signals to produce a plurality of synchronized signals and combining the
plurality of synchronized signals in accordance with the quality of each of
the plurality of synchronized signals to produce the resultant signal.”
Petitioner argues that this subject matter is met by referring to its contentions
for the “processor” limitation of claim 22 and citing Gilhousen390’s
disclosure of adjusting the timing of signals and aligning the signals.
Pet. 48–49 (citing Ex. 1006, 8:18–21, 13:21–32; Ex. 1003 ¶¶ 167–168).
Patent Owner argues that Petitioner has not proven unpatentability of
these claims for the reasons given for claim 28, from which these claims
depend. PO Resp. 54. For claim 30, Patent Owner additionally argues that,
because Gilhousen865 and Gilhousen390 do not teach determining a best
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fixed radio port, they cannot disclose “determin[ing] a plurality of best fixed
radio ports.” PO Resp. 54–55 (citing Ex. 2100 ¶¶ 195–196). For the reasons
explained above in § II.D.7, we disagree with Patent Owner’s arguments
regarding determining a “best fixed radio port,” and we find that the
combination of Gilhousen865 and Gilhousen390 teaches this subject matter.
Based on Petitioner’s contentions and evidence, summarized above,
we are persuaded that the subject matter recited in claims 29–31 would have
been obvious based on the combination of Gilhousen865 and Gilhousen390.
9. Dependent Claims 32 and 33
Claim 32 depends from claim 22 and recites
wherein the amount of information transferred to the mobile unit
is maximized by transmitting the information through at least one
of the plurality of fixed radio ports, the at least one fixed radio
port providing a greatest quality communication link between the
at least one fixed radio port and the mobile unit in relation to
other communication links between other fixed radio ports of the
plurality of fixed radio ports and the mobile unit.
Petitioner argues that this subject matter is met by referring to its
contentions for the “processor” limitation of claim 22 and citing
Gilhousen865’s disclosure of providing communication channels between
the ground base station and the radiotelephones and searching for the
strongest pilot signal from the ground base station. Pet. 49–50 (citing
Ex. 1005, 2:24–29, Figs. 1, 2; Ex. 1003 ¶¶ 171–172).
Claim 33 depends from claim 32 and recites that “the greatest quality
communication link comprises: a first wireless communication link between
the at least one fixed radio port and the receiver; and a second wireless
communication link between the transmitter and the mobile unit.” Petitioner
argues that this subject matter is met by referring to its contentions for
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claim 32 and citing Gilhousen865’s disclosure of providing communication
links between the ground base station and the airborne base station and
between the airborne base station and the phones on the aircraft. Pet. 50–52
(citing Ex. 1005, 3:36–40, 4:1–5, Figs. 1, 2; Ex. 1003 ¶¶ 174–178).
Patent Owner does not dispute Petitioner’s contentions for these
claims, apart from its arguments as to independent claim 22, which we
address above in § II.D.3.
Based on Petitioner’s contentions and evidence, summarized above,
we are persuaded that the subject matter recited in claims 32 and 33 would
have been obvious based on the combination of Gilhousen865 and
Gilhousen390.
10. Dependent Claim 40
Claim 40 depends from claim 34 and recites “wherein the processor is
further adapted to establish a second communication link between the
plurality of mobile units and at least a second fixed radio port of the plurality
of fixed radio ports based on the plurality of signal quality indicators.”
Petitioner argues that this subject matter is met by referring to its
contentions for the “receiver” and “processor” limitations of claim 22 and
citing Gilhousen390’s disclosure of handling calls through different cell sites
based on signal strength. Pet. 56–57 (citing Ex. 1006, 12:67–13:20;
Ex. 1003 ¶¶ 196–199). Petitioner argues that, “by establishing
communication links with multiple ground base stations, a [person of
ordinary skill in the art] would have understood that the combination of
Gilhousen865 and Gilhousen390 teaches the elements of claim 40.” Pet. 57
(citing Ex. 1003 ¶¶ 198–199).
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Similar to its argument for claim 34, Patent Owner argues that
Gilhousen390’s control processor is in the mobile unit, not in a mobile base
station, and, therefore, that Gilhousen390’s control processor “does not
establish any communication link between a plurality of mobile units and a
fixed radio port.” PO Resp. 63 (emphasis omitted). As discussed for
claim 34 in § II.D.4.d above, Patent Owner’s arguments do not account for
the combined teachings of Gilhousen865 and Gilhousen390. In particular,
Petitioner relies on Gilhousen390’s disclosure of selecting cell sites based on
signal strength in combination with Gilhousen865’s disclosures of an
airborne base station with a call control processor. Pet. 54–55, 56–57; see
also Pet. Reply 19 (“[W]hen Gilhousen390’s processing techniques are
incorporated into Gilhousen865’s airborne base station, the Gilhousen865-
Gilhousen390 combination teaches these claim elements.”). Thus, we
disagree with Patent Owner’s arguments as to claim 40.
Based on Petitioner’s contentions and evidence, summarized above,
we are persuaded that the subject matter recited in claim 40 would have been
obvious based on the combination of Gilhousen865 and Gilhousen390.
E. Obviousness over Gilhousen865
(Claim 56)
Petitioner asserts that claim 56 of the ’904 patent is unpatentable
under 35 U.S.C. § 103(a) as obvious over the teachings of Gilhousen865.
1573 Pet. 6, 26–37.
1. Preamble
The preamble of claim 56 recites “[a] method of providing a
communication connection between a communication network and a
plurality of mobile units having a motion relative to a plurality of fixed
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ports, wherein the plurality of fixed ports are communicatively coupled to
the communication network.” Petitioner argues that Gilhousen865’s ground
base stations, which are coupled to the public switched telephone network
(PSTN), teach a “plurality of fixed ports [that] are communicatively coupled
to the communication network.” 1573 Pet. 29–30 (citing Ex. 1005, 2:21–29,
Fig. 1). Petitioner argues that Gilhousen865’s radiotelephones on the
aircraft move relative to the ground base stations and therefore teach “a
plurality of mobile units having a motion relative to a plurality of fixed
ports.” 1573 Pet. 28 (citing Ex. 1005, 2:46–52, 2:57–59, Fig. 2; Ex. 102916
¶ 102). Petitioner argues that Gilhousen865’s disclosure of providing
communications between the ground communication network and the
phones on the airplane teaches “providing a communication connection
between a communication network and a plurality of mobile units.”
1573 Pet. 26–32.
Patent Owner argues that Gilhousen865’s radiotelephones are not
“mobile units” under its proposed construction. PO Resp. 91. For the
reasons explained above in § II.D.3.a.ii, we disagree with Patent Owner and
we find that Gilhousen865 teaches a “plurality of mobile units” by
disclosing multiple radiotelephones on the aircraft. Ex. 1005, 2:57–59
(“This subsystem may have a single radiotelephone, as in a small aircraft, or
multiple radiotelephones, as in an airline size aircraft.”), Fig. 2.
Based on Petitioner’s contentions and evidence, summarized above,
we are persuaded that Gilhousen865 teaches the subject matter recited in the
preamble of claim 56 (whether or not limiting).

16 This exhibit is the declaration of Dr. Ding for IPR2019-01573, which was
filed as Exhibit 1003 in that proceeding.
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2. Establishing a first communication link
Claim 56 recites “establishing a first communication link between the
plurality of mobile units and a first fixed port of the plurality of fixed ports
through a movable base station having a motion in accordance with the
motion of the mobile units.” Petitioner argues that Gilhousen865’s airborne
base station teaches “a movable base station” through which the phones on
the aircraft and the ground base stations communicate. 1573 Pet. 33–35
(citing Ex. 1005, 2:24–29, 3:3–5, 3:7–10, 4:1–8, Figs. 1, 2; Ex. 1029 ¶¶ 108–
109). Petitioner further argues that Gilhousen865’s airborne base station has
“a motion in accordance with the motion of the mobile units” because it
moves with the phones on the plane as the plane moves. 1573 Pet. 35 (citing
Ex. 1029 ¶ 110).
Patent Owner does not dispute these contentions. See PO Resp. 89–
91. We are persuaded by Petitioner’s contentions, and we find that
Gilhousen865’s disclosure of providing communications between the
radiotelephones on the airplane through the airborne base station to the
ground base stations teaches this subject matter. Ex. 1005, 3:3–5 (disclosing
“an airborne base station that has the ability to register the radiotelephones
on the aircraft”), 4:1–5 (disclosing that, “[o]nce the radiotelephone is
registered with the aircraft base station, the aircraft base station then
searches for the strongest pilot signal from a ground base station and
registers with that base station”).
3. Simultaneously handing off
Claim 56 recites “simultaneously handing off the plurality of mobile
units to a second fixed port of the plurality fixed ports.” Petitioner cites
Gilhousen865’s disclosure of starting a hand-off process when the plane
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reaches the fringe of the cell site and its disclosure of the airborne base
station registering the airborne radiotelephones with the ground base
stations. 1573 Pet. 35–36 (citing Ex. 1005, 3:3–7, 4:1–5, 3:52–59, 6:19–24;
Ex. 1029 ¶ 112). Petitioner contends that a person of ordinary skill in the art
would have “recognized that the hand-off process would occur
‘simultaneously’ for the radiotelephones because the radiotelephones are all
connected through the same airborne base station” and “would have found it
obvious to implement a simultaneous hand-off process to ensure that each
radiotelephone maintains quality service.” 1573 Pet. 36 (citing Ex. 1029
¶ 114).
In its Response, Patent Owner argues that Gilhousen865 does not
teach that a movable base station performs a handoff but, rather, that
“Gilhousen865 explicitly discloses that its ‘hand off’ function is performed
by its radiotelephone.” PO Resp. 89–90 (citing Ex. 1005, 3:52–59). Thus,
in its Response, Patent Owner’s argument focuses on which device performs
the handoff in Gilhousen865. See PO Resp. 89–90. In its Sur-reply, Patent
Owner changes its position, arguing that Gilhousen865 does not even
disclose a handoff: “Gilhousen865 discloses how the airborne unit
determines that a hand off is required and does not disclose that or even how
a hand off is to be performed.” PO Sur-reply 27 (citing Ex. 1005, 3:59–62;
Ex. 2100 ¶ 92). Patent Owner’s Sur-reply position is similar to Mr.
Lanning’s testimony that “Gilhousen865 and/or Tiedemann do not disclose a
handoff of any type.” Ex. 2100 ¶ 285.
We disagree with Patent Owner’s later position that Gilhousen865
does not disclose a handoff. Gilhousen865 states that a problem with
existing aircraft phone systems is that they do not perform hand-offs
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between cells, which results in dropped calls. Ex. 1005, 1:36–41. In light of
this problem in the art, Gilhousen865 explains that “an airborne
radiotelephone system is needed that enables ground initiated telephone calls
to be received by the airborne radiotelephone in addition to the call from the
airborne radiotelephone being handed off to the next cell as it reaches the
edge of the cell’s coverage.” Ex. 1005, 1:44–48, quoted in part in
Pet. Reply 20. To this end, Gilhousen865 explains that “[a]nother benefit of
the present invention is the hand-off capability,” such that “[o]nce the
aircraft reaches the fringe of the present cell site, the radiotelephone begins
the hand-off process.” Ex. 1005, 3:52–55. Thus, Gilhousen865 expressly
discloses a “hand-off.”
Patent Owner argues that Gilhousen865 only discloses registering the
phone with a base station and that a person of ordinary skill in the art “would
understand that ‘registration’ and a ‘handoff’ are significantly different
functions in a cellular network.” PO Sur-reply 27 (citing Ex. 2100 ¶ 92).
According to Patent Owner, “a ‘handoff’ occurs when the mobile unit
commences communications with a new base station on the same CDMA
frequency assignment before terminating communications with the old base
station.” PO Sur-reply 27. We are not persuaded by Patent Owner’s
assertion that a handoff requires the same CDMA frequency assignment
because it lacks evidentiary support. Mr. Lanning testifies that Tiedemann’s
disclosure “is not a hand-over or hand-off because no voice or data
connection is moving from the current cell to the new cell.” Ex. 2100 ¶ 95.
Thus, Mr. Lanning’s testimony suggests that a hand-off includes moving a
call from one cell to a new cell. This is what Gilhousen865 teaches by
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disclosing “the call from the airborne radiotelephone being handed off to the
next cell as it reaches the edge of the cell’s coverage.” Ex. 1005, 1:44–48.
Mr. Lanning also testifies about various scenarios in which a handoff
may not work in Gilhousen865 because “the overlapping of cells” necessary
for hand-offs “would not occur at many different altitudes.” Ex. 2100 ¶ 93.
Mr. Lanning further testifies that, “[i]f the base stations were positioned
close to each other to provide overlap at the lower altitudes, there would be a
large amount of overlap at the higher altitudes resulting in an inefficient
system.” Ex. 2100 ¶ 93 n.5. This testimony simply reflects design
considerations that would have to be weighed by a person of ordinary skill in
the art depending on the application. For example, efficient coverage at high
altitudes may mean that there is less coverage at lower altitudes. These
considerations do not detract from Gilhousen865’s express disclosure of a
“call from the airborne radiotelephone being handed off to the next cell as it
reaches the edge of the cell’s coverage.” Ex. 1005, 1:44–48. Thus, whether
or not Gilhousen865 discloses an inefficient system, it is still “prior art for
all that it teaches.” Beckman Instruments, Inc. v. LKB Produkter AB, 892
F.2d 1547, 1551 (Fed. Cir. 1989).
As noted above, in its Response, Patent Owner argues that
Gilhousen865 does not teach that a movable base station performs a handoff
but, rather, that “Gilhousen865 explicitly discloses that its ‘hand off’
function is performed by its radiotelephone.” PO Resp. 89–90 (citing
Ex. 1005, 3:52–59). We agree with Patent Owner that the cited portion of
Gilhousen865 discloses that the radiotelephone performs the hand-off.
Ex. 1005, 3:53–55 (“Once the aircraft reaches the fringe of the present cell
site, the radiotelephone begins the hand-off process described in
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Tiedemann.”). But this is describing one embodiment in which the aircraft
contains a repeater that “register[s] the radiotelephone with the nearest cell
site” “in the same manner as a terrestrial radiotelephone registers with the
ground based radiotelephone system.” Ex. 1005, 3:15–20. Petitioner relies
on Gilhousen865’s disclosure of an “an alternate embodiment” in which “the
radiotelephone signal repeater is replaced by an airborne base station that
has the ability to register the radiotelephones on the aircraft” (Ex. 1005, 3:3–
5). 1573 Pet. 35 (citing Ex. 1005, 3:3–7). Petitioner argues that, in this
embodiment, a person of ordinary skill in the art would have “recognized
that the hand-off process would occur ‘simultaneously’ for the
radiotelephones because the radiotelephones are all connected through the
same airborne base station” and “would have found it obvious to implement
a simultaneous hand-off process to ensure that each radiotelephone
maintains quality service.” 1573 Pet. 36 (citing Ex. 1029 ¶ 114). Patent
Owner’s argument about hand-offs being performed by the phone (PO
Resp. 89–90) fails to appreciate Gilhousen865’s airborne base station
embodiment. Furthermore, Patent Owner’s argument that Gilhousen865
discloses registration, not handoff (PO Sur-reply 27), is not persuasive for
the reasons discussed above.
For the reasons explained above, we are persuaded, and we find, that
Gilhousen865 discloses performing hand-offs and that the airborne base
station performs the hand-offs in Gilhousen865’s “alternate embodiment.”
Ex. 1029 ¶¶ 112–114; Ex. 1030 ¶¶ 43–45. We also are persuaded, and we
find, that the hand-off process occurs simultaneously for multiple phones
“because the radiotelephones are all connected through the same airborne
base station,” such that “when the airborne base station switches its
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connection to a new ground base station, all onboard radiotelephones would
follow the airborne base station as being connected to the new ground base
station.” Ex. 1029 ¶ 114.
Based on Petitioner’s contentions and evidence and in view of the
foregoing discussion, we find Gilhousen865 teaches “simultaneously
handing off the plurality of mobile units to a second fixed port of the
plurality fixed ports,” as recited in claim 56.
4. Determination of unpatentability
For the reasons discussed above, we find that Gilhousen865 teaches
the subject matter recited in claim 56, and based on the full trial record, we
conclude that Petitioner has demonstrated that the subject matter recited in
claim 56 would have been obvious over the teachings of Gilhousen865.
F. Obviousness over Gilhousen865 and Gilhousen390
(Claims 57–59)
Petitioner asserts that claims 57–59 of the ’904 patent are
unpatentable under 35 U.S.C. § 103(a) as obvious over the combined
teachings of Gilhousen865 and Gilhousen390. 1573 Pet. 6, 37–51.
Claim 57 recites the following:
A method in accordance with claim 56, wherein the step of
simultaneously handing off the plurality of mobile units
comprises the steps of:
combining a first incoming signal transmitted from the
first fixed port and a second incoming signal transmitted from
the second fixed port to produce a resultant signal; and
transmitting the resultant signal to the plurality of mobile
units from the movable base station.
Petitioner acknowledges that “Gilhousen865 does not explicitly
disclose combining signals from a first and second ground base station,” and
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Petitioner relies on Gilhousen390’s disclosure of receiving signals from
multiple cell sites. 1573 Pet. 43–44 (citing Ex. 1006, 11:55–62, Fig. 1;
Ex. 1029 ¶¶ 132–134). Gilhousen390 discloses receiving signals from
multiple cell sites to continue a call as a phone moves out of a coverage area,
as follows:
Should mobile unit 16 move out of the coverage area of
the initial cell-site, cell-site 12, an attempt is made to continue
the call by routing the call through another cell-site. In the cell
diversity mode the call is routed through multiple cell-sites. The
use of the diversity receiver system of the present invention
enables communications between mobile unit 16 and cell-sites
12, 14 and various other cell-sites.
Ex. 1006, 11:55–62.
Petitioner further argues that Gilhousen390 discloses techniques for
combining signals from different cell sites to produce a resultant signal,
which would be routed to the phones on the aircraft in combination with
Gilhousen865’s system. Pet. 46–48 (citing Ex. 1006, 13:21–32; Ex. 1029
¶¶ 136, 138–139). For example, Gilhousen390 discloses “diversity
combiner and decoder circuitry,” which “adjusts the timing of the two
streams of received signals into alignment and adds them together.”
Ex. 1006, 13:21–25.
Petitioner argues that a person of ordinary skill in the art “would have
been motivated to modify Gilhousen865’s system with any one or more of
the signal diversity configurations of Gilhousen390 at least for the purpose
of reducing errors caused by well-known deleterious effects on
wirelessly-transmitted signals.” 1573 Pet. 41–42 (citing Ex. 1029 ¶ 128).
Petitioner further argues that a person of ordinary skill in the art “would
have been motivated to implement the cell-site diversity mode of
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Gilhousen390 at the airborne base station of Gilhousen865 to optimize the
signal transmitted from the base station to the radiotelephone, at least during
the hand-off process when signals are received from two ground base
stations.” 1573 Pet. 46–47 (citing Ex. 1029 ¶ 136). According to Petitioner,
a person of ordinary skill in the art “would have had a reasonable
expectation of success in combining the system of Gilhousen865 with the
teachings of Gilhousen390 using known methods, and the results of the
combination would have been predictable to a [person of ordinary skill in
the art] (e.g., an airborne base station capable of tracking and combining
multiple signal paths)” and “would involve nothing more than incorporating
well-known concepts (i.e., Gilhousen390’s diversity techniques) into a well-
known system (i.e., Gilhousen865’s radio communication system).”
1573 Pet. 42–43 (citing Ex. 1029 ¶ 129).
Claim 58 recites the following:
A method in accordance with claim 57, wherein the step of
combining comprises the steps of:
determining a first quality of the first signal;
determining a second quality of the second signal; and
adding the first signal to the second signal in accordance
with the first quality and the second quality.
Petitioner argues that Gilhousen390’s disclosure of measuring signal
strength in different paths and multiplying the signal streams by a number
corresponding to the relative strengths of the streams before adding the
streams together teaches this subject matter. 1573 Pet. 48–50 (citing
Ex. 1006, 8:11–15, 13:21–32; Ex. 1029 ¶ 140–145). For example,
Gilhousen390 discloses that “[t]he diversity combiner circuitry contained
within circuitry 48 simply adjusts the timing of the two streams of received
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signals into alignment and adds them together. This addition process may be
proceeded17 by multiplying the two streams by a number corresponding to
the relative signal strengths of the two streams.” Ex. 1006, 13:22–28.
Claim 59 recites “[a] method in accordance with claim 58, wherein
the step of adding comprises the step of minimizing a contribution of the
first signal to the resultant signal by ignoring the first signal.” Petitioner
argues that this subject matter would have been obvious in view of
Gilhousen390’s disclosure of multiplying each signal by a number
corresponding to the signal strength, which would be zero in Gilhousen865
when the airplane has left the first cell site and the signal from that site,
therefore, is no longer useful. 1573 Pet. 50–51 (citing Ex. 1005, 3:55–62,
4:36–44; Ex. 1006, 13:25–28; Ex. 1029 ¶¶ 146–149).
Patent Owner relies on the arguments against the combination of
Gilhousen865 and Gilhousen 390 that we address above in § II.D.3.e. See
PO Resp. 26–37. Patent Owner also argues that “Gilhousen390 does not
disclose or imply the required limitations of a moveable base station
‘simultaneously handing off the plurality of mobile units’ or ‘establishing a
first communication link between the plurality of mobile units.’” PO Resp.
91–92. As discussed above in § II.E, Petitioner relies on Gilhousen865 to
teach these limitations of claim 56, and we are persuaded that Gilhousen865
teaches this subject matter. Patent Owner does not otherwise dispute
Petitioner’s contentions that Gilhousen390 in combination with
Gilhousen865 teaches the limitations of claims 57–59.

17 In context, it appears that the drafter intended to say “preceded” to
indicate that the multiplication occurs before the addition.
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Based on Petitioner’s persuasive contentions and evidence,
summarized above, and for the reasons discussed above in this section and in
§ II.D.3.e (addressing claim 22), we conclude, based on the full trial record,
that Petitioner has demonstrated that the subject matter recited in claims 57–
59 would have been obvious over the combined teachings of Gilhousen865
and Gilhousen390.
G. Remaining Grounds
As noted above in § I.A, Petitioner presents separate challenges to
claims 22, 23, 28–35, 40, 50, 51, and 56–59 based on Vercauteren alone or
in combination with other references. Because we determine that these
claims are unpatentable as discussed above, we need not separately assess
the patentability of these claims based on the remaining grounds in this
proceeding. 35 U.S.C. § 318(a) (“If an inter partes review is instituted and
not dismissed under this chapter, the Patent Trial and Appeal Board shall
issue a final written decision with respect to the patentability of any patent
claim challenged by the petitioner and any new claim added under section
316(d).”).
H. Constitutionality
Patent Owner contends that “adjudication of the ’904 patent violates
the U.S. Constitution” because “the current structure of the Board violates
the Appointments Clause of Article II.” PO Resp. 96–97.
In Arthrex v. Smith & Nephew, 941 F.3d 1320, 1338 (Fed. Cir. 2019),
cert. granted sub nom. United States v. Arthrex, Inc., 2020 WL 6037206
(Oct. 13, 2020), the Federal Circuit determined that the current structure of
the Board does not violate Article II as of the date of that precedential
decision. See also Arthrex, Inc. v. Smith & Nephew, Inc., 953 F.3d 760, 764
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(Fed. Cir. 2020) (Moore, J., concurring in denial of rehearing) (“Because the
APJs were constitutionally appointed as of the implementation of the
severance, inter partes review decisions going forward were no longer
rendered by unconstitutional panels.”). Furthermore, in Arthrex, the Federal
Circuit found “no constitutional infirmity in the institution decision as the
statute clearly bestows such authority on the Director pursuant to 35 U.S.C.
§ 314.” 941 F.3d at 1340.
Therefore, we disagree with Patent Owner that this Final Written
Decision and our Institution Decision are “invalid.” PO Resp. 97.

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III. CONCLUSION
For the reasons discussed above, we determine Petitioner has proven,
by a preponderance of the evidence, that the challenged claims are
unpatentable, as summarized in the following table:

18 As explained above, because we determine that the challenged claims are
unpatentable on other grounds, we decline to address this ground and the
remaining grounds involving Vercauteren.
Claim(s)
35
U.S.C. §
Reference(s)/Basis
Claims
Shown
Unpatentable
Claims
Not Shown
Unpatentable
22, 23,
28–35,
40, 50,
51
103(a) Gilhousen865,
Gilhousen390
22, 23, 28–35,
40, 50, 51

56 103(a) Gilhousen865 56
57–59 103(a) Gilhousen865,
Gilhousen390
57–59
22, 23,
28, 29,
32–35,
40, 50,
51
103(a) Vercauteren,
Forssén18

30, 31 103(a) Vercauteren,
Forssén,
Gilhousen390

56 102(b) Vercauteren
57, 58 103(a) Vercauteren,
Gilhousen390

59 103(a) Vercauteren,
Gilhousen390,
Forssén

Overall
Outcome
22, 23, 28–35,
40, 50, 51,
56–59

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IV. ORDER
Accordingly, it is:
ORDERED that claims 22, 23, 28–35, 40, 50, 51, and 56–59 of the
’904 patent have been shown to be unpatentable; and
FURTHERED ORDERED that, because this is a Final Written
Decision, parties to the proceeding seeking judicial review of the Decision
must comply with the notice and service requirements of 37 C.F.R. § 90.2.
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PETITIONER:
Ryan Richardson
Michael Specht
Steven Pappas
Daniel Yonan
STERNE KESSLER GOLDSTEIN & FOX
rrichardson-ptab@sternekessler.com
mspecht-ptab@sternekessler.com
spappas-ptab@sternekessler.com
dyonan-ptab@sternekessler.com

PATENT OWNER:
R. Scott Rhoades
Sanford E. Warren, Jr.
WARREN RHOADES, LLP
srhoades@wriplaw.com
swarren@wriplaw.com

Charles Gavrilovich
GAVRILOVICH, DODD & LINDSEY, LLP
chuck@gdllawfirm.com

Elvin Smith
LAW OFFICES OF ELVIN E. SMITH,
III PLLC
esmith@eeslaw.com