NOTE: This disposition is nonprecedential.

United States Court of Appeals 

for the Federal Circuit ______________________ 

INTEL CORPORATION,

Appellant

v.

PACT XPP SCHWEIZ AG,

Appellee

______________________ 

2022-1139

______________________ 

Appeal from the United States Patent and Trademark 

Office, Patent Trial and Appeal Board in No. IPR2020-

00539.

______________________ 

Decided: February 24, 2023

______________________ 

JOHN C. O'QUINN, Kirkland & Ellis LLP, Washington, 

DC, argued for appellant. Also represented by DIVA R.

HOLLIS, NATHAN S. MAMMEN; ROBERT ALAN APPLEBY,

JAMES E. MARINA, New York, NY.

SANFORD IAN WEISBURST, Quinn Emanuel Urquhart & 

Sullivan, LLP, New York, NY, argued for appellee. Also 

represented by NIMA HEFAZI, FREDERICK A. LORIG, Los Angeles, CA; MARK YEH-KAI TUNG, Redwood Shores, CA. 

______________________ 

Case: 22-1139 Document: 39 Page: 1 Filed: 02/24/2023
2 INTEL CORPORATION v. PACT XPP SCHWEIZ AG

Before NEWMAN, PROST, and HUGHES, Circuit Judges.

PROST, Circuit Judge. 

The Patent Trial and Appeal Board (“Board”) determined that Intel, Inc. (“Intel”) failed to prove certain challenged claims of U.S. Patent No. 9,552,047 (“the ’047 

patent”) were unpatentable as obvious. Intel Corp. v. 

PACT XPP Schweiz AG, No. IPR2020-00539, Paper 35

(P.T.A.B. Sept. 8, 2021) (“’539 Final Written Decision”). We 

reverse. 

BACKGROUND

Intel petitioned for inter partes review of several patents owned by PACT XPP Schweiz AG (“PACT”). Three 

resulting Board decisions are relevant to this appeal. First, 

in the ’535 proceeding, the Board determined that Intel 

proved some, but not all, challenged claims of U.S. Patent 

No. 8,312,301 (“the ’301 patent”) were unpatentable as obvious. Intel Corp. v. PACT XPP Schweiz AG, No. IPR2020-

00535, Paper 33, 2021 WL 3506785 (P.T.A.B. Aug. 9, 2021) 

(“’535 Final Written Decision”). Second, in the ’541 proceeding, the Board determined that Intel proved all challenged claims of U.S. Patent No. 9,075,605 (“the ’605 

patent”) were unpatentable as obvious. Intel Corp. v. 

PACT XPP Schweiz AG, No. IPR2020-00541, Paper 36, 

2021 WL 8776166 (P.T.A.B. Aug. 31, 2021) (“’541 Final 

Written Decision”). And finally, in the ’539 proceeding on 

appeal here, the Board determined that Intel proved some, 

but not all, challenged claims of the ’047 patent were unpatentable as obvious. ’539 Final Written Decision, at 87.

Case: 22-1139 Document: 39 Page: 2 Filed: 02/24/2023
INTEL CORPORATION v. PACT XPP SCHWEIZ AG 3

The ’301, ’605, and ’047 patents all relate to optimizing 

power consumption in multiprocessor systems.1 Power optimization is important for maximizing battery life and 

maintaining suitable temperatures for multiprocessor systems. There are a few ways to optimize power in a multiprocessor system, but the one at issue in this case focuses 

on adjusting “clock frequency.” The clock frequency of a 

processor refers to the rate at which that processor can process data; the faster the frequency, the faster a processor 

can complete a task. See id. at 3.

Three claims of the ’047 patent are representative for 

purposes of this appeal. We address each in turn.

I 

Claim 2, in relevant part, claims a multiprocessor system 

wherein for at least some of the [processors], the 

clock frequency is adjustable at runtime according 

to a state of the multiprocessor system.

’047 patent claim 2 (emphasis added); see Appellee’s Br. 6 

n.1. 

Intel relied on prior art reference Nicol2 to teach this 

“according to a state” limitation. The Board concluded that 

Nicol failed to disclose this limitation because Nicol taught 

adjusting clock frequency only according to an “anticipated” state, and the Board construed the claim to require 

adjusting clock frequency according to an “existing” state. 

’539 Final Written Decision, at 15, 38. 

1 “The ’047 patent is a divisional of the ’605 patent, 

and the ’605 patent is a continuation of the ’301 patent.” 

Appellant’s Br. 26.

2 U.S. Patent No. 6,141,762 (“Nicol”).

Case: 22-1139 Document: 39 Page: 3 Filed: 02/24/2023
4 INTEL CORPORATION v. PACT XPP SCHWEIZ AG

Without explanation as to why or how, the Board 

reached a contrary conclusion in the ’535 proceeding when 

analyzing representative claim 12 of the ’301 patent. 

Claim 12 of the ’301 patent claimed a multiprocessor device 

wherein[] . . . the clock frequency of each [processor] is at least determinable by a state of the [multiprocessor] device

’301 patent claim 12 (emphasis added); see Appellee’s 

Br. 6 n.1. In the ’535 proceeding, the Board concluded that 

Nicol taught that “state” limitation even if “state” were construed to include only “existing” states. ’535 Final Written 

Decision, 2021 WL 3506785, at *28. 

II

Claim 7, in relevant part, claims a multiprocessor system that’s

adapted to . . . reduce the clock frequency in accordance with a hysteresis characteristic[]. 

’047 patent claim 7 (emphasis added).3 In a generic sense, 

hysteresis is “[a]ny phenomenon in which there is a lag between the cause and the induced or observed effect.” 

J.A. 2738; see also J.A. 2413 l. 20–2414 l. 11.

Intel also relied on Nicol to teach the “hysteresis characteristic” limitation of claim 7. But, according to the 

Board, Nicol did not disclose this limitation because the 

hysteresis in Nicol’s system was the result of a 

3 The original claim language reads “in accordance 

with a hysteresis characteristics.” ’047 patent claim 2. The 

parties agree that the final “s” in “characteristics” is a typo. 

See Appellant’s Br. 57 n.9; Appellee’s Br. 2. We accordingly 

refer to this limitation hereinafter as a singular “hysteresis 

characteristic.”

Case: 22-1139 Document: 39 Page: 4 Filed: 02/24/2023
INTEL CORPORATION v. PACT XPP SCHWEIZ AG 5

“predetermined choice.” ’539 Final Written Decision, at 50

(cleaned up). 

Yet in the ’541 proceeding, the Board followed the opposite logic. There, Intel asserted that prior art Kling4

taught the “hysteresis characteristic” limitation in representative claim 1 of the ’605 patent. Claim 1 of the ’605 

patent claimed a method for operating a multiprocessor 

system in which

the multiprocessor system . . . reduc[es] the clock 

frequency of . . . at least [a] part of the multiprocessor system in accordance with . . . a hysteresis characteristic. 

’605 patent claim 1 (emphasis added). The Board found 

that Kling disclosed this limitation based on Kling’s teaching of a system that implemented hysteresis “by comparing 

the same signal against two thresholds,” ’541 Final Written 

Decision, 2021 WL 8776166, at *16, where those two 

thresholds were predetermined by the user, id. at *21. 

III

Claim 10, in relevant part, claims a multiprocessor system comprising

a plurality of temperature sensors and a heterogeneous plurality of clocked [processors]; and 

wherein 

the multiprocessor having a plurality of regions, a 

temperature sensor being provided for each of said 

plurality of regions to measure the temperature of 

said specific region; and

4 U.S. Patent No. 6,367,023 (“Kling”).

Case: 22-1139 Document: 39 Page: 5 Filed: 02/24/2023
6 INTEL CORPORATION v. PACT XPP SCHWEIZ AG

the clock frequencies of said [processors] being dynamically adjustable in accordance with the sensed 

temperatures. 

’047 patent claim 10; see Appellee’s Br. 6 n.1. Intel argued, 

and PACT did not dispute, that a combination of Nicol and 

Bhatia5 disclosed these limitations. But PACT did dispute 

that a person of ordinary skill would have been motivated 

to combine Nicol and Bhatia. The Board agreed with 

PACT. Although Intel had argued that a person of ordinary skill would have been motivated to use “Bhatia’s approach of partitioning a system or chip into multiple 

thermal zones, each monitored by its own thermal sensor,” 

with Nicol’s system, ’539 Final Written Decision, at 73

(cleaned up), the Board concluded that Intel’s expert testimony that this approach would have been “beneficial” was 

“unsupported by record evidence,” id. at 75 (citing 

J.A. 2772 ¶ 42).

This finding stands in direct contrast to the Board’s 

finding that there was a motivation to combine Nicol and 

Bhatia in the ’535 proceeding to render representative 

claim 3 of the ’301 patent obvious. Claim 3 of the ’301 patent claimed a method of operating a multiprocessor system by

grouping . . . a plurality of subsets of [processors] . . . 

effecting a plurality of temperature measurements 

in different regions of the system; and

based on the temperature measurement, . . . modifying clock rates of the plurality of subsets of [processors] . . . . 

’301 patent claim 3; see Appellee’s Br. 6 n.1. The Board 

found, in that proceeding, that Intel had demonstrated a 

5 U.S. Patent No. 6,535,798 (“Bhatia”).

Case: 22-1139 Document: 39 Page: 6 Filed: 02/24/2023
INTEL CORPORATION v. PACT XPP SCHWEIZ AG 7

person of ordinary skill would have thought it “beneficial” 

to combine Nicol and Bhatia to render this claim obvious 

because “a person of ordinary skill in the art would have 

understood that Bhatia’s approach of partitioning a system 

or chip into multiple thermal zones, each monitored by its 

own thermal sensor, . . . . would improve the accuracy of 

Nicol’s . . . system.” ’535 Final Written Decision, 2021 WL 

3506785, at *18 (cleaned up).

Intel appeals the Board’s ’539 Final Written Decision

with respect to claims 2–4, 7, 9–11, 13, and 27. We have 

jurisdiction under 28 U.S.C. § 1295(a)(4)(A).

DISCUSSION

Intel appeals the Board’s determination that claims 

2–4, 7, 9–11, 13, and 27 were not unpatentable as obvious. 

Intel asserts that the Board’s conclusions are erroneous 

both on the merits and under the Administrative Procedure Act (“APA”) as a result of the inconsistent conclusions 

between this proceeding and the ’535 and ’541 proceedings. 

Because we agree with Intel on the merits of each challenge, we need not address its APA arguments. 

On the merits, Intel challenges the Board’s claim construction of “state” for claims 2–4; claim construction of 

“hysteresis characteristic” for claims 7, 9, 13, and 27; and 

factual finding of no motivation to combine Nicol and 

Bhatia for claims 10 and 11. 

Claim construction is a question of law reviewed de 

novo. Data Engine Techs. LLC v. Google LLC, 10 F.4th 

1375, 1380 (Fed. Cir. 2021). Obviousness is ultimately a 

question of law reviewed de novo with subsidiary fact-findings, like motivation to combine, reviewed for substantial 

evidence. PersonalWeb Techs., LLC v. Apple, Inc., 917 F.3d 

1376, 1381 (Fed. Cir. 2019). “Substantial evidence is such 

relevant evidence as a reasonable mind might accept as adequate to support a conclusion.” Novartis AG v. Torrent 

Pharms. Ltd., 853 F.3d 1316, 1324 (Fed. Cir. 2017).

Case: 22-1139 Document: 39 Page: 7 Filed: 02/24/2023
8 INTEL CORPORATION v. PACT XPP SCHWEIZ AG

We agree with Intel on the merits of all claims on appeal and accordingly reverse. 

I 

Intel argues that the Board’s determination that 

claims 2–4 were not unpatentable relies on an incorrect 

claim construction of “state.” Appellant’s Br. 44–50. We 

agree. 

Claim 2 claims a multiprocessor system in which clock 

frequency for at least some processors “is adjustable at 

runtime according to a state.” ’047 patent claim 2 (emphasis added). The Board construed “according to a state” to 

require that “the clock frequency is adjusted as a result of, 

or in response to, an existing state of the multiprocessing 

system or its [processors].” ’539 Final Written Decision, 

at 15 (emphasis added). In doing so, the Board explicitly 

credited PACT’s argument that adjusting clock frequency 

“according to a state” excluded adjusting clock frequency 

according to an “anticipated” state. See id. at 11–13. The 

Board reasoned that anticipated-state clock frequency adjustments were excluded from the claim because the ’047

specification describes changing clock frequency in response to only a variety of “preexisting” inputs, like the described “configuration state.” See id. at 13–15.

On appeal, Intel argues that the Board’s construction 

of “according to a state” is wrong because it excludes embodiments disclosed in the ’047 patent. Appellant’s 

Br. 44–45 (first citing Oatey Co. v. IPS Corp., 514 F.3d 

1271, 1276–77 (Fed. Cir. 2008); then citing GE Lighting 

Sols., LLC v. AgiLight, Inc., 750 F.3d 1304, 1309 (Fed. Cir. 

2014); and then citing Golden Bridge Tech., Inc. v. Apple 

Inc., 758 F.3d 1362, 1365 (Fed. Cir. 2014)). PACT responds 

that the Board’s construction is correct because the embodiments on which Intel relies aren’t covered by the claim due 

to the claim’s “at runtime” limitation. Appellee’s Br. 28–30.

Case: 22-1139 Document: 39 Page: 8 Filed: 02/24/2023
INTEL CORPORATION v. PACT XPP SCHWEIZ AG 9

We start with the plain and ordinary meaning of the 

claim according to a person of ordinary skill. See Phillips 

v. AWH Corp., 415 F.3d 1303, 1313 (Fed. Cir. 2005) (en 

banc). “[C]lock frequency is adjustable at runtime according to a state of the multiprocessor system” does not limit 

“state” to existing states. That plain and ordinary meaning 

corresponds with the intrinsic evidence, which describes 

embodiments adjusting clock frequency according to an anticipated state. ’047 patent col. 3 ll. 1–22; id. at col. 4 

ll. 17–19; id. at col. 4 ll. 65–66. 

PACT admits that the ’047 patent describes embodiments that adjust clock frequency according to an anticipated state. However, PACT argues that “Intel [cannot] 

show that those [anticipated-state] embodiments concern 

claims 2–4” since claims 2–4 require clock frequency adjustment “at runtime.” Appellee’s Br. 29. PACT instead 

suggests that the anticipated-state embodiments concern 

other claims, like claim 1. Oral Arg. at 23:20–46, 

No. 22-1139, https://oralarguments.cafc.uscourts.gov/default.aspx?fl=22-1139_12072022.mp3. We are not persuaded by this argument. As an initial matter, the Board 

did not rely on the “at runtime” language to exclude the 

anticipated-state embodiments; it relied on the “according 

to” language. See ’539 Final Written Decision, at 12. But 

even worse, PACT’s argument makes no sense on the merits. Claim 1 also includes the “at runtime” limitation on 

which PACT relies. See ’047 patent claim 1 (“[T]he clock 

frequency is adjustable at runtime . . . .”). And we discern

no lexicography or disavowal excluding the anticipatedstate embodiments from the scope of claims 2–4. See 

Golden Bridge, 758 F.3d at 1365.

Accordingly, we construe claims 2–4 to include adjusting clock frequency according to an anticipated state. The 

parties agree that, under such a construction, these claims 

are obvious, see Oral Arg. at 24:29–50, so we reverse the 

Board’s contrary conclusion.

Case: 22-1139 Document: 39 Page: 9 Filed: 02/24/2023
10 INTEL CORPORATION v. PACT XPP SCHWEIZ AG

II

Intel argues that the Board’s determination that 

claims 7, 9, 13, and 27 were not unpatentable relies on an 

incorrect claim construction of “hysteresis characteristic.” 

Appellant’s Br. 58–59. We agree.

Claim 7 claims a multiprocessor system that’s “adapted 

to . . . reduce the clock frequency in accordance with a hysteresis characteristic.” ’047 patent claim 7 (emphasis 

added). The Board noted that the ’047 patent “contains no 

helpful description” of what a hysteresis characteristic is. 

’539 Final Written Decision, at 46. So, without objection 

from PACT, the Board accepted Intel’s “understanding” of 

“hysteresis” for the purposes of its analysis. Id. at 47. Intel, in part, described hysteresis as

involv[ing] the nonlinear response of a circuit, in 

which the response to a particular set of input conditions depends both on the instantaneous values 

and the recent past of the input and output signal, 

with such behavior further characterized as the inability to retract exactly on the reverse swing of a 

particular set of input and output conditions. 

Id.

Hysteresis is commonly used to avoid excessive switching. The parties agree that a modern thermostat is an example of a circuit that exhibits hysteresis, and we adopt 

PACT’s description as illustrative:

Suppose [a] thermostat’s goal is to keep the room 

at approximately 70 degrees, and the thermostat is 

set to a window between 68 degrees and 72 degrees. 

Suppose further that the starting temperature before the thermostat is turned on is 66 degrees. 

Once turned on, the thermostat will trigger the 

heater to start, and the heater will stay on until the 

thermostat senses that the room’s temperature is 

72 degrees. At that point, the thermostat will tell 

Case: 22-1139 Document: 39 Page: 10 Filed: 02/24/2023
INTEL CORPORATION v. PACT XPP SCHWEIZ AG 11

the heater to turn off. The room’s temperature will 

gradually decline during this “heater off” period 

until it reaches 68 degrees, at which point the thermostat will tell the heater to turn back on, and the 

cycle will repeat.

Appellee’s Br. 39–40 (emphasis in original). Compare such 

a two-threshold system to one with a single threshold: suppose, still, that the thermostat’s goal is to keep the room at 

approximately 70 degrees but that the thermostat turns 

the heater on and off as soon as the room temperature even 

slightly deviates from that single measure. The twothreshold thermostat avoids excessively switching the 

heater on and off using hysteresis, which results in energy 

savings.

On appeal, Intel argues that the Board implicitly and 

incorrectly construed “hysteresis characteristic” in determining that Nicol did not teach this limitation. Appellant’s 

Br. 58–64. Intel asserts that the Board precluded “hysteresis characteristic” from covering systems that use programmed hysteresis, like the thermostat. See id. at 58–59. 

PACT responds that “the Board did not make a distinction 

between programmed hysteresis and naturally-occurring 

hysteresis.” Appellee’s Br. 40. According to PACT, the 

Board’s construction “still involves a response by [a] programmed system” but requires that “that response is not 

entirely predetermined.” Id. at 40–41 (cleaned up). To put 

that in terms of the thermostat, PACT says that a thermostat “adapted to . . . reduce the [room temperature] in accordance with a hysteresis characteristic” doesn’t cover a 

thermostat that employs the two-threshold system if, say, 

the heater has a preset time following the room temperature reaching one of the thresholds before it turns on or off. 

But see J.A. 609 (“Lag is a form of hysteresis.”).

We start with the plain and ordinary meaning of the 

claim according to a person of ordinary skill. Phillips, 

415 F.3d at 1313. A “hysteresis characteristic,” according 

Case: 22-1139 Document: 39 Page: 11 Filed: 02/24/2023
12 INTEL CORPORATION v. PACT XPP SCHWEIZ AG

to the Board’s understanding of “hysteresis,” includes at 

least a “nonlinear response of a circuit” and an “inability to 

retrace exactly on the reverse swing of a particular set of 

input and output conditions.” ’539 Final Written Decision, 

at 47.6 Neither of those characteristics preclude a predetermined response, and PACT points us to no other intrinsic or extrinsic evidence that otherwise indicates such a 

limitation is warranted.

Accordingly, we construe claims 7, 9, 13, and 27 to 

cover reducing clock frequency according to a hysteresis 

characteristic, even if that characteristic is the result of, in 

whole or in part, a predetermined choice. The parties agree 

that, under such a construction, these claims are obvious, 

see Oral Arg. at 37:17–32, so we reverse the Board’s contrary conclusion.

III

Intel argues that the Board’s determination that 

claims 10 and 11 were not unpatentable relies on a finding 

of no motivation to combine that lacks substantial evidence. Appellant’s Br. 74–76. We agree.

There’s no dispute that Nicol and Bhatia disclose all 

limitations of claims 10 and 11. The only dispute is 

whether an artisan of ordinary skill would have been motivated to combine those reference. See Appellee’s Br. 48–49. 

6 This means the claim covers a multiprocessor system “adapted to . . . reduce the clock frequency in accordance with,” ’047 patent claim 7, “a nonlinear response of 

[the] circuit” or an “inability to retrace . . . on the reverse 

swing” of that response, ’539 Final Written Decision, at 47. 

The meaning of such a claim is unclear, but we need not

resolve that question in the context of this appeal because 

the parties seem to agree that the dispute is whether a hysteresis characteristic may or may not be the result of a “deliberate choice.” See id. at 50.

Case: 22-1139 Document: 39 Page: 12 Filed: 02/24/2023
INTEL CORPORATION v. PACT XPP SCHWEIZ AG 13

The Board found that such an artisan wouldn’t have been 

motivated, explaining that Intel’s argument that such a 

combination would have been “beneficial” lacked record evidence. ’539 Final Written Decision, at 75. 

The Board’s rationale for finding a lack of motivation 

to combine is neither reasonable nor correct. The Board 

cited Intel’s expert testimony in stating that Intel’s motivation to combine argument was “unsupported by record 

evidence.” See id. (citing J.A. 2772 ¶ 42). That expert testimony, in turn, cites to Bhatia, which explains that its 

“temperature sensor[s]” monitor and control corresponding 

“thermal zones” to maintain system temperature within a 

certain range. Bhatia col. 3 ll. 29–39; see J.A. 2772 ¶ 42 

(citing Bhatia col. 3 ll. 29–39). Bhatia teaches that these 

temperature controls are useful because different processors can have different workloads; and a higher workload 

risks a high temperature; and a high processor temperature could cause circuit failure. Bhatia col. 1 ll. 5–59. 

Intel’s expert explained that it would be “beneficial” to 

implement a similar temperature control system with 

Nicol because “the different [processors in Nicol] can [also]

have different workloads and thus different temperature 

profiles.” J.A. 849 ¶ 249 (citing Nicol col. 5 ll. 42–44); see

J.A. 2772 ¶ 41 (citing J.A. 849 ¶ 249). The cited passage of 

Nicol explains that different processors may be subject to 

different voltages; and a low voltage risks a low temperature; and a low processor temperature could also cause circuit failure. Nicol col. 5 ll. 42–44. And the relationship 

between workloads and voltage was well known in the 

art—the higher the workload, the higher the voltage 

needed to process that workload given a set period of time. 

See id. at col. 5 ll. 23–24, 42–44 (explaining that Nicol’s system “react[s] to variations in the system[’s] [work]load” by, 

in part, changing voltage supply). 

We fail to see how this record evidence is lacking. The 

Board’s citations directly explain how temperature

Case: 22-1139 Document: 39 Page: 13 Filed: 02/24/2023
14 INTEL CORPORATION v. PACT XPP SCHWEIZ AG

regulation is beneficial in monitoring and controlling multiprocessors since those processors could be subject to different voltages (like in Nicol) or different workloads (like in 

Bhatia). We thus reverse the Board’s finding on motivation 

to combine and accordingly determine that claims 10 and 

11 are obvious.

* * * 

We reject the Board’s claim construction of “state” and 

“hysteresis characteristic” and reverse its finding of a lack 

of motivation to combine Nicol and Bhatia.

CONCLUSION

We have considered PACT’s remaining arguments and 

find them unpersuasive. For the foregoing reasons, we reverse the Board’s judgment that claims 2–4, 7, 9–11, 13, 

and 27 are not obvious. 

REVERSED

Case: 22-1139 Document: 39 Page: 14 Filed: 02/24/2023