NOTE: This disposition is nonprecedential.

United States Court of Appeals 

for the Federal Circuit ______________________ 

HITACHI METALS, LTD.,

Appellant

v.

ALLIANCE OF RARE-EARTH PERMANENT 

MAGNET INDUSTRY,

Appellee

______________________ 

2016-1824, 2016-1825

______________________ 

Appeals from the United States Patent and Trademark Office, Patent Trial and Appeal Board in Nos. 

IPR2014-01265, IPR2014-01266.

______________________ 

Decided: July 6, 2017

______________________ 

MARC A. HEARRON, Morrison & Foerster LLP, Washington, DC, argued for appellant. Also represented by 

BRIAN ROBERT MATSUI, SETH W. LLOYD; MEHRAN 

ARJOMAND, Los Angeles, CA.

KIRK T. BRADLEY, Alston & Bird LLP, Charlotte, NC, 

argued for appellee. Also represented by MICHAEL S.

CONNOR; CHRISTOPHER BRANTLEY KELLY, Atlanta, GA.

______________________ 
2 HITACHI METALS, LTD. v. ALLIANCE OF RARE-EARTH

Before LOURIE, TARANTO, and CHEN, Circuit Judges.

LOURIE, Circuit Judge. 

Hitachi Metals, Ltd. (“Hitachi”) appeals from final 

written decisions of the U.S. Patent and Trademark Office 

(“the PTO”) Patent Trial and Appeal Board (“the Board”) 

in two inter partes reviews (“IPRs”), concluding that 

claims 1, 5, and 6 of U.S. Patent 6,537,385 (“the ’385 

patent”) and claims 1–4, 11, 12, and 14–16 of U.S. Patent 

6,491,765 (“the ’765 patent”) would have been obvious at 

the time of their respective inventions and that claim 1 of 

the ’385 patent was anticipated. See All. of Rare-Earth 

Permanent Magnet Indus., IPR 2014-01265, 2016 Pat. 

App. LEXIS 1082, at *41 (P.T.A.B. Feb. 8, 2016) (“’385 

Decision”); All. of Rare-Earth Permanent Magnet Indus., 

IPR 2014-01266, 2016 Pat. App. LEXIS 1083, at *56 

(P.T.A.B. Feb. 8, 2016) (“’765 Decision”). For the reasons 

set forth below, we affirm in part and vacate and remand

in part.

BACKGROUND

Hitachi owns the ’385 and ’765 patents (together, “the 

challenged patents”), which have almost identical written 

descriptions and are directed to a process for manufacturing a powder used to produce rare-earth magnets. See, 

e.g., ’765 patent col. 1 ll. 7–9.1 Claim 1 of the ’385 patent 

is representative and reads as follows:

A method for manufacturing alloy powder for R–

Fe–B rare earth magnets, comprising a first pulverization step of coarsely pulverizing an R–Fe–B 

 

1 Because the challenged patents have almost identical written descriptions, we will refer only to the ’765 

patent written description for simplicity when discussing 

either patent.
HITACHI METALS, LTD. v. ALLIANCE OF RARE-EARTH 3

alloy for rare earth magnets produced by a rapid 

cooling method and a second pulverization step of 

finely pulverizing the material alloy, 

wherein said second pulverization step 

comprises a step of removing at least 

part of the powder in which the concentration of rare earth element is greater 

than the average concentration of rare 

earth element contained in the entire 

powder. 

’385 patent col. 13 ll. 19–37. The “R–Fe–B” designation 

refers to a mixture of a rare earth element (R), iron (Fe), 

and boron (B). Dependent claim 5 requires the further 

step of cooling “a molten material alloy at a cooling rate in 

a range between 102 oC./sec and 104 oC./sec.” Id. col. 14 ll. 

1–4. Dependent claim 6 requires that the molten material alloy be cooled by a “strip casting method.” Id. col. 14 

ll. 5–6.

Claim 1 of the ’765 patent is representative and reads 

as follows:

A method for manufacturing alloy powder for R–

Fe–B rare earth magnets, comprising a first pulverization step of coarsely pulverizing a material 

alloy for rare earth magnets and a second pulverization step of finely pulverizing the material alloy, 

wherein said first pulverization step comprises a step of pulverizing the material 

alloy by a hydrogen pulverization 

method, and 

said second pulverization step comprises a 

step of removing at least part of fine 

powder having a particle size of 1.0 μm 

or less to adjust the particle quantity of 

the fine powder having a particle size of 
4 HITACHI METALS, LTD. v. ALLIANCE OF RARE-EARTH

1.0 μm or less to 10% or less of the particle quantity of the entire powder.

’765 patent col. 13 ll. 21–33. Dependent claim 3 requires 

that the fine pulverization step be performed “in a highspeed flow of gas,” which dependent claim 4 requires to be 

“oxygen.” Id. col. 13 ll. 39–43. Dependent claims 11 and 

12 resemble claims 5 and 6, respectively, of the ’385 

patent, as discussed above. Id. col. 14 ll. 16–21.

The Alliance of Rare-Earth Permanent Magnet Industry (“the Alliance”) filed requests for IPR of the challenged 

patents, which the PTO granted. The Board concluded 

that claims 1, 5, and 16 of the ’385 patent and claims 1–4, 

11, 12, and 14–16 of the ’765 patent would have been 

obvious over various combinations of: (1) Japanese Patent 

1993-283217 to Hasegawa (“Hasegawa”); (2) U.S. Patent 

4,992,234 to Ohashi et al. (“Ohashi”); (3) U.S. Patent 

5,383,978 to Yamamoto et al. (“Yamamoto”); and (4) 

Shuixiao He, Rare Earth Permanent Magnet Milling 

Equipment – Jet Mill Closed Loop System, 21 MAGNETIC 

MATERIALS AND PARTS, 48–51 (Oct. 1990) (“He”). The 

Board also concluded that claim 1 of the ’385 patent was 

anticipated by He. 

I. ’385 Patent

The Board concluded that claims 1, 5, and 6 of the 

’385 patent would have been obvious over either Hasegawa, Ohashi, or He and Yamamoto, and that claim 1 was 

anticipated by He. In making its obviousness determinations, the Board relied on Hasegawa, Ohashi, and He for 

teaching every element of claim 1 except the “rapid cooling method,” for which it relied on Yamamoto. Hitachi 

did not dispute those findings. Hitachi argued only that 

one of ordinary skill in the art would not have been motivated to combine those references. 
HITACHI METALS, LTD. v. ALLIANCE OF RARE-EARTH 5

A. Obviousness over Ohashi/Hasegawa and Yamamoto

The Board, crediting the Alliance’s arguments, found 

that one of ordinary skill would have been motivated to 

combine Ohashi or Hasegawa with Yamamoto because it 

was understood that Yamamoto’s rapid cooling method 

produces a more uniform alloy, so one of ordinary skill 

would have been motivated to combine the references “in 

order to pulverize a more uniform R–Fe–B material 

alloy.” ’385 Decision, 2016 Pat. App. LEXIS 1082, at *16–

17, *21–22. Hitachi did not dispute that Yamamoto’s 

rapid cooling method would result in a more uniform 

alloy, but rather argued that one of ordinary skill would 

not have been motivated to pulverize a more uniform 

alloy because the consequence would have been a 50% or 

more reduction in yield. See id. at *18–19. 

The Board rejected Hitachi’s arguments, explaining 

that, even if Hitachi were correct that the combination 

would have resulted in a significantly diminished yield, 

such commercial considerations “do[] not control the 

obviousness determination,” especially since the claims do 

not require a certain minimum yield. Id. at *21. Instead, 

the Board relied on the Alliance’s evidence that the 

claimed steps were each known in the art and used for 

their known purpose and that the result of the combination would have been predictable. Id. at *21, *27–28. The 

Board found that a skilled artisan would have known how 

to combine the references because the ingot (Ohashi and 

Hasegawa) and strip casting (Yamamoto) methods were 

“interchangeable to those skilled in the art.” Id. at *13, 

*27. Furthermore, the Board found that “design incentives,” such as “lower cost [and a] more productive [process] better suited for higher volume manufacturing,” 

would have led one of ordinary skill to pursue the combination. Id. at *21–22, *27–28. 

Hitachi did not dispute that Yamamoto teaches the 

limitations of claims 5 and 6 of the ’385 patent, and the 
6 HITACHI METALS, LTD. v. ALLIANCE OF RARE-EARTH

Board concluded that those claims would also have been 

obvious over Ohashi or Hasegawa and Yamamoto for the 

same reasons as claim 1. 

B. Obviousness over He and Yamamoto

The Board also concluded that claims 5 and 6 would 

have been obvious over He and Yamamoto. The Board 

relied on He for teaching every limitation except for the 

cooling rate range of claim 5 and the “strip casting method” of claim 6, for which it relied on Yamamoto. Hitachi 

did not dispute that the references teach those limitations, but rather argued that there would not have been a 

motivation to combine them. The Board rejected the 

Alliance’s argument that one of ordinary skill would have 

been motived to combine He with Yamamoto’s cooling rate 

because Yamamoto’s method would result in a more 

uniform alloy. Id. at *38–39. The Board found that the 

Alliance’s evidence was lacking because it did not explain 

how Yamamoto’s particular cooling rate would differ from 

He’s disclosed “quick quenching,” Joint Appendix (“J.A.”) 

705. ’385 Decision, 2016 Pat. App. LEXIS 1082, at *38. 

However, the Board found persuasive the Alliance’s 

evidence that the claims encompass nothing more than 

the “combination of prior art elements according to known 

methods to yield a predictable result.” Id. at *39–40. 

Thus, the Board concluded that claims 5 and 6 would 

have been obvious over He and Yamamoto. 

C. Anticipation by He

The Board found that He anticipated claim 1. The 

dispute before the Board focused on whether He’s disclosed “quick quenching,” J.A. 705, constitutes the 

claimed “rapid cooling method,” ’385 patent col. 13 l. 22. 

Thus, the Board first construed “rapid cooling method.” 

’385 Decision, 2016 Pat. App. LEXIS 1082, at *10–11. 

Hitachi argued that a skilled artisan would have interpreted He’s disclosed “quick quenching” method to be a 

“super-rapid cooling,” rather than a “rapid cooling,” 
HITACHI METALS, LTD. v. ALLIANCE OF RARE-EARTH 7

method. Specifically, Hitachi argued, one of ordinary skill 

would have interpreted “quick quenching” as referring to 

“melt spinning,” a super-rapid cooling method that employs cooling rates “in excess of 106 K s-1,” because strip 

casting methods were not known in 1990. Id. at *32–33. 

Hitachi argued that the written description defines the 

range of cooling rates covered by the term “rapid cooling” 

as being between 102–104 oC./sec and thus He does not 

disclose the “rapid cooling method” as properly construed. 

The Board rejected Hitachi’s construction based on 

principles of claim differentiation—it found that, because 

dependent claim 5 recites “a cooling rate in a range between 102 oC./sec and 104 oC./sec,” claim 1’s recitation of 

“rapid cooling method” must “encompass a broader range 

of cooling rates” and thus does not “necessarily exclude 

super-rapid cooling methods.” Id. at *10–11. Under that 

construction, the Board found that He’s disclosed “quick 

quenching” constitutes the claimed “rapid cooling method”

and that claim 1 was anticipated by He. Id. at *34. 

II. ’765 Patent

A. Obviousness over Ohashi and Hasegawa

The Board concluded that claims 1–4, 14, and 16 of 

the ’765 patent would have been obvious over Ohashi and 

Hasegawa. In making its obviousness determination, the 

Board relied on Ohashi for teaching every element of 

claim 1, except the requirement that the “first pulverization step comprises a step of pulverizing the material 

alloy by a hydrogen pulverization method,” ’765 patent 

col. 13 ll. 26–28 (emphasis added), for which it relied on 

Hasegawa. Hitachi did not dispute those findings, but 

rather argued only that one of ordinary skill in the art 

would not have been motivated to combine the references. 

The Board found that one of ordinary skill would have 

been motived to employ Hasegawa’s hydrogen pulverization method to “improve the coarse pulverization” taught 
8 HITACHI METALS, LTD. v. ALLIANCE OF RARE-EARTH

by Ohashi because the Alliance’s evidence shows that 

hydrogen pulverization “more easily crush[es] the material alloy.” ’765 Decision, 2016 Pat. App. LEXIS 1083, at 

*16–18. The Board credited the Alliance’s evidence that 

hydrogen pulverization allows the process to occur “in 

one-fourth of the time required by [Ohashi’s] mechanical 

pulverization” and that it also “improves pulverization 

yield and pulverization efficiency.” Id. at *29, *30 (internal quotation marks omitted). Further, the Board found 

that one of ordinary skill would have had a reasonable 

expectation of success in combining the references, which 

disclose “well-known and common technique[s],” and that 

the results would have been predictable. Id. at *29.

As for dependent claims 2, 3, 14, and 16, Hitachi 

made no additional arguments and the Board concluded 

that those claims would have been obvious over Ohashi

and Hasegawa for the same reasons as claim 1. Id. at 

*31.

Hitachi did, however, assert separate arguments relating to the Board’s obviousness determination of claim 

4, which depends from claim 3 and requires that the 

“pulverization step” be conducted “in a high-speed flow of 

gas” (claim 3), “wherein the gas comprises oxygen” (claim 

4). ’765 patent col. 13 ll. 39–43. Hitachi argued that 

Ohashi teaches the use of a high-speed flow of gas (i.e., an

“air stream,” J.A. 699) for particle classification only, not 

for finely pulverizing the alloy, as required by claim 4. 

The Board rejected that argument, determining that 

claim 1, from which claim 4 depends, comprises two 

pulverization steps: (1) a first pulverization step of coarse 

pulverization; and (2) a second pulverization step, which 

in turn comprises the two “sub-step[s]” of (i) fine pulverization, a.k.a. “milling,” and (ii) particle classification, i.e. 

removal of particles having a particular size. ’765 Decision, 2016 Pat. App. LEXIS 1083, at *37. The Board 

concluded that the two sub-steps constitute one continu-
HITACHI METALS, LTD. v. ALLIANCE OF RARE-EARTH 9

ous process under the umbrella “second pulverization 

step”—thus, a reference teaching the second sub-step 

necessarily teaches the umbrella “second pulverization 

step.” Id. at *35–37. And the Board interpreted claim 4 

as requiring a high-speed flow of oxygen for the umbrella

step, not the first sub-step. Id. at *37–38. Under that 

interpretation, the Board found that Ohashi teaches 

“pulverization” using a “high-speed flow of [oxygen] gas,” 

as recited in claim 4, because it teaches using an “air 

stream” for particle classification (i.e., the second substep) and an “air stream” necessarily includes some 

amount of oxygen gas. Id. at *38.

B. Obviousness over Ohashi, Hasegawa, and Yamamoto

The Board concluded that dependent claims 11 and 

12 would have been obvious over Ohashi, Hasegawa, and 

Yamamoto. Hitachi again disputed only the combinability 

of those references for the same reasons it had previously 

articulated. The Board rejected those arguments, finding

a motivation to combine Ohashi and Hasegawa for the 

same reasons as for claim 1 of the ’765 patent and a 

motivation to combine either Ohashi or Hasegawa with 

Yamamoto for the same reasons as for claim 1 of the ’385 

patent. 

Hitachi timely appealed to this court. We have jurisdiction pursuant to 28 U.S.C. § 1295(a)(4)(A). 

DISCUSSION

We review the Board’s legal conclusions de novo and 

its factual findings for substantial evidence. In re Gartside, 203 F.3d 1305, 1316 (Fed. Cir. 2000). A finding is 

supported by substantial evidence if a reasonable mind 

might accept the evidence as adequate to support the 

conclusion drawn therefrom. Consol. Edison Co. v. 

NLRB, 305 U.S. 197, 217 (1938). Obviousness is a question of law based on underlying facts. Apple Inc. v. Samsung Elecs. Co., 839 F.3d 1034, 1047 (Fed. Cir. 2016) (en 
10 HITACHI METALS, LTD. v. ALLIANCE OF RARE-EARTH

banc). What the prior art teaches, whether a person of 

ordinary skill in the art would have been motivated to 

combine references, and whether a reference teaches 

away from the claimed invention are questions of fact. Id.

at 1047–48; In re Mouttet, 686 F.3d 1322, 1330 (Fed. Cir. 

2012).

On appeal, Hitachi argues that the Board erred in: 

(1) finding a motivation to combine the references in its 

obviousness determinations for both of the challenged 

patents; (2) construing “rapid cooling method” and finding, under that construction, that He anticipates claim 1 

of the ’385 patent; and (3) construing claim 4 of the ’765 

patent and thus in its obviousness determination of that

claim. We discuss each of the challenged patents in turn.

I. ’385 Patent

A. Obviousness over Ohashi or Hasegawa and Yamamoto

The Board concluded that claims 1, 5, and 6 of the 

’385 patent would have been obvious over Hasegawa or 

Ohashi in view of Yamamoto. 

Hitachi makes almost identical arguments for both of 

the combinations relied upon by the Board—namely, that 

one of skill in the art would not have been motivated to 

combine Ohashi or Hasegawa with Yamamoto because the 

results of pulverizing the more uniform alloy produced by 

Yamamoto’s rapid cooling method would be a 50% or more 

reduction in yield and a lower quality magnet. 

Hitachi argues that the Board erred in dismissing its 

evidence regarding the potentially lower yield as a “commercial [consideration that] does not control the obviousness determination.” ’385 Decision, 2016 Pat. App. LEXIS 

1082, at *20. Hitachi notes the apparent contradiction

between that reasoning and the Board’s subsequent 

finding that one of skill in the art would be motivated to 

combine the references due to “design incentives,” such as 

“lower cost [and a] more productive [process] better suited 
HITACHI METALS, LTD. v. ALLIANCE OF RARE-EARTH 11

for higher volume manufacturing.” Id. at *21–22, *27, 

*28. Hitachi also disputes the Board’s findings that all of 

the claims would have been obvious because they “represent the combination of prior art elements according to 

known methods to yield a predictable result.” See, e.g., id.

at *21 (citing KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 

416 (2007)). Hitachi argues that those findings are merely “boilerplate” recitations that state a conclusion, not a 

reason to combine the references.

The Alliance responds that the factual findings underpinning the Board’s obviousness determinations were 

supported by substantial evidence. 

We conclude that the Board did not err in determining

that claims 1, 5, and 6 of the ’385 patent would have been 

obvious over Ohashi or Hasegawa in view of Yamamoto. 

We do agree with Hitachi that the Board applied internally inconsistent reasoning in rejecting Hitachi’s evidence 

on the basis that “commercial [considerations] do[] not 

control the obviousness determination,” id. at *20, while 

also finding that one of skill in the art would have been 

motivated to combine the references due to “design incentives,” id. at *21. If the Board’s analysis had stopped 

there, we might remand for further analysis that is not 

internally inconsistent. 

However, the Board made additional findings to support its obviousness determinations, including that one of 

skill in the art would have known to mitigate the alleged 

reduction in yield by adjusting the jet mill settings during 

pulverization. See, e.g., id. at *19, *28 (citing expert 

testimony that “a person of ordinary skill would have 

known to adjust basic, fundamental jet milling settings to 

accommodate the uniform particle size and shape distribution of the strip cast alloy” (internal quotation marks 

and brackets omitted)). That finding was supported by 

substantial record evidence. See J.A. 788. 
12 HITACHI METALS, LTD. v. ALLIANCE OF RARE-EARTH

Hitachi points to countervailing testimony by the 

same expert that, while a skilled artisan would have

known to adjust the settings, they would not have known 

how to do so, as the “multi-parameter compositional 

experimentation” required would be beyond the capabilities of one of ordinary skill. J.A. 972. However, we do not 

“reweigh evidence on appeal.” In re NTP, Inc., 654 F.3d 

1279, 1292 (Fed. Cir. 2011). We must accept the Board’s 

finding so long as a “reasonable mind might accept [the 

evidence upon which it relied] as adequate to support [its] 

conclusion.” Consol. Edison Co., 305 U.S. at 217. The 

Board reviewed the competing evidence and made a 

factual determination that a skilled artisan would not 

have been demotivated by the potential reduction in yield. 

We see no error in that finding, which was a reasonable 

interpretation of the record evidence. 

In light of the foregoing, the Board found that the 

claims were directed to nothing more than a “combination 

of prior art elements according to known methods to yield 

a predictable result.” ’385 Decision, 2016 Pat. App. 

LEXIS 1082, at *21, *24. The Supreme Court has advised 

that a combination of known elements is likely to be 

obvious when it yields predictable results. KSR, 550 U.S. 

at 416. And substantial evidence supports the Board’s 

findings that the prior art elements were well-known, one 

of ordinary skill would have known how to combine them, 

and the results of so doing would have been predictable. 

See ’385 Decision, 2016 Pat. App. LEXIS 1082, at *18, *20, 

*27, *39.

B. Obviousness over He and Yamamoto

The Board found that claims 5 and 6 would have also 

been obvious over He and Yamamoto. As for those claims, 

Hitachi repeats several of its arguments regarding the 

Board’s determinations of obviousness over Ohashi or 

Hasegawa and Yamamoto. Namely, Hitachi disputes the 

Board’s finding that the claims are directed to nothing 
HITACHI METALS, LTD. v. ALLIANCE OF RARE-EARTH 13

more than the “combination of prior art elements according to known methods to yield a predictable result.” Id. at 

*39–40. Hitachi argues that such findings are merely 

boilerplate recitations that state a conclusion, not a 

reason to combine the references. Furthermore, Hitachi 

challenges the credibility of the Alliance’s expert declaration, relied upon by the Board, as making bald assertions 

that lack evidentiary support. 

We affirm the Board’s conclusion that claims 5 and 6 

would have been obvious over He and Yamamoto for the 

reasons discussed above regarding the obviousness of 

claim 1, 5, and 6 over Ohashi/Hasegawa and Yamamoto. 

We see no legal error in the Board’s analysis, and we do 

not reweigh evidence on appeal. 

C. Anticipation by He 

The Board found that He anticipated claim 1. On appeal, Hitachi challenges the Board’s construction of “rapid 

cooling method,” arguing, as it did before the Board, that 

one of ordinary skill would have understood “rapid cooling 

method” to be distinct from “super rapid cooling.” Hitachi 

asserts that, at the time of the invention, one of ordinary 

skill would have recognized three categories of methods 

for preparing alloys for sintered rare-earth magnets: 

(1) traditional cooling methods, such as ingot casting; 

(2) rapid cooling methods, such as strip casting; and 

(3) super-rapid cooling methods, such as melt spinning. 

Hitachi submitted evidence—expert testimony and other 

printed publications—indicating that one of ordinary skill 

would have understood the three categories to be distinct, 

such that “rapid cooling” refers to a method that is faster 

than ingot casting, but not so fast that it enters the domain of super-rapid cooling. Hitachi argues that the 

written description defines the range of cooling rates 

covered by the term because it states: “In the rapid cooling method, the molten alloy is cooled at a rate in the 

range between 102 oC./sec and 104 oC./sec.” ’385 patent 
14 HITACHI METALS, LTD. v. ALLIANCE OF RARE-EARTH

col. 1 ll. 46–47. In contrast, Hitachi argues, super rapid 

cooling methods were understood by those of skill in the 

art as exceeding 106 degrees per second. Therefore, 

Hitachi argues, one of skill in the art would have understood He’s disclosed “quick quenching” to be a “super 

rapid cooling” method rather than the claimed “rapid 

cooling method” and thus He did not anticipate claim 1.

The Alliance responds that the Board correctly construed “rapid cooling method.” The Alliance argues that 

the written description provides a clear definition of the 

term when it describes rapid cooling as “typified by a strip 

casting method,” wherein “a molten material alloy is put 

into contact with a single chill roll, twin chill rolls, a 

rotary chill disk, a rotary cylindrical chill mold, or the 

like, to be rapidly cooled thereby producing a solidified 

alloy thinner than an ingot cast alloy.” Id. col. 1 ll. 39–45. 

The Alliance contends that the Board correctly adopted 

that definition, finding in it no exclusion of rates in excess 

of 106 oC./sec. Furthermore, the Alliance argues, claim 5, 

which depends from claim 1, recites “a cooling rate in a 

range between 102 and 104 oC./sec,” id. col. 14 l. 4, and 

claim 6, which depends from claim 5, specifies that the 

rapid cooling method is a “strip casting method,” id. col. 

14 l. 6. Thus, the Alliance maintains, claim 1’s recitation 

of “rapid cooling method” must encompass rates outside of 

the range recited in claim 5 and methods other than the 

strip casting recited in claim 6, and therefore claim 1 was 

anticipated by He. 

We agree with the Alliance that the doctrine of claim 

differentiation requires that the scope of “rapid cooling 

method” covered by claim 1 be broader than the range

specified in dependent claim 5 (102–104 oC./sec). See id.

col. 14 ll. 1–4. Hitachi argues that, even if claim differentiation requires the range of claim 1 to be slightly broader 

than 102–104 oC./sec, it does not require the range to be so 

broad as to include rates in excess of 106 degrees per 
HITACHI METALS, LTD. v. ALLIANCE OF RARE-EARTH 15

second, which one of ordinary skill would understand to 

constitute super-rapid cooling. 

However, nowhere does the written description accord 

with Hitachi’s argument, nor does it anywhere indicate 

that “rapid cooling” must exclude cooling at rates in 

excess of 106 degrees per second. Rather, the written 

description states that “[i]n a preferred embodiment, the 

material alloy for rare earth magnets is obtained by 

cooling a molten material alloy at a cooling rate in the 

range between 102 oC./sec and 104 oC./sec.” Id. col. 3 ll. 

51–54 (emphasis added). The patent expressly refers to 

the range recited by claim 5 as a “preferred embodiment.” 

Id. Thus, “rapid cooling method,” as recited in claim 1, 

must encompass a broader range than that recited in 

claim 5 and nowhere does the specification cap the range

at 106 degrees per second. Consequently, the Board’s 

construction of “rapid cooling method” as not excluding

“super rapid cooling” is supported by the intrinsic record 

and we affirm that construction.

Hitachi premises the remainder of its challenges to 

the Board’s anticipation finding on its proposed construction of “rapid cooling method.” Thus, because we affirm 

the Board’s construction, we affirm its finding that He

anticipated claim 1. Accordingly, the Board was correct in 

concluding that claim 1, as properly construed, was anticipated by He. 

II. ’765 Patent

A. Obviousness over Ohashi and Hasegawa

The Board concluded that claims 1–4, 14, and 16 of 

the ’765 patent would have been obvious over Ohashi and

Hasegawa. Hitachi challenges the Board’s findings that 

one of ordinary skill would have been motivated to employ 

Hasegawa’s hydrogen pulverization to “improve the coarse 

pulverization” taught by Ohashi because the Alliance’s 

evidence shows that hydrogen pulverization “more easily 
16 HITACHI METALS, LTD. v. ALLIANCE OF RARE-EARTH

crush[es] the material alloy,” and hydrogen pulverization 

was a “well-known and common technique” that would 

have yielded predictable results when substituted for 

Ohashi’s mechanical pulverization. ’765 Decision, 2016 

Pat. App. LEXIS 1083, at *16–18, *29 (internal quotation 

marks omitted). 

Hitachi contends that the Board erred in accepting 

the bald assertions of the Alliance’s expert that lacked 

supporting evidence. Hitachi points to its evidence that, 

in order to substitute Hasegawa’s hydrogen pulverization 

for Ohashi’s mechanical pulverization, the solid alloy 

must accordingly be changed to the proper microstructure, but changing the microstructure of the solid alloy 

would completely alter Ohashi’s operating principle. 

Thus, Hitachi argues, the combination would have required more than ordinary skill. Furthermore, Hitachi 

contends that the Board improperly shifted the burden by 

requiring Hitachi to show that the combination would 

have been beyond the capability of one of ordinary skill. 

The Alliance responds that substantial evidence supports the Board’s finding of a motivation to combine. 

We agree with the Alliance that substantial evidence 

supports the Board’s findings for claims 1, 2, 14, and 16. 

The Board credited the Alliance’s evidence that one of 

ordinary skill would have been motived to employ Hasegawa’s hydrogen pulverization to “improve the coarse 

pulverization” taught by Ohashi because the Alliance’s 

evidence shows that hydrogen pulverization “more easily 

crush[es] the material alloy,” id. at *16–18; hydrogen 

pulverization allows the process to occur “in one-fourth of 

the time required by [Ohashi’s] mechanical pulverization,” id. at *29; hydrogen pulverization “improves pulverization yield and pulverization efficiency” over mechanical 

pulverization, id. at *29 (internal quotation marks omitted); one of ordinary skill would have had a reasonable 

expectation of success in combining the references, which 
HITACHI METALS, LTD. v. ALLIANCE OF RARE-EARTH 17

disclose “well-known and common technique[s],” id. at 

*29; and the results would have been predictable, id. We 

conclude that the foregoing constitutes substantial evidence to support the Board’s determination. 

Hitachi primarily disputes the credibility of the Alliance’s evidence and presents its own competing evidence. 

But we do not reweigh the evidence considered by the 

Board and, in this case, we conclude that its interpretation of the evidence was reasonable.

B. Obviousness of Claim 4

Hitachi separately argues that claim 4 would not have 

been obvious over Ohashi and Hasegawa. Hitachi contends that the Board improperly construed claim 4. 

Hitachi argues that the specification contradicts the 

Board’s construction—i.e., that a high-speed flow of gas 

for particle classification, as taught by Ohashi, satisfies 

the limitations of claims 3 and 4—because it distinguishes 

between the two sub-steps of fine pulverization and 

particle classification as separate steps, rather than one 

continuous step. Hitachi points to the language of claim 

1, which recites that the “second pulverization step of 

finely pulverizing the material alloy . . . comprises a step 

of removing at least part of the fine powder,” ’765 patent 

col. 13 ll. 24–31 (emphasis added), and argues that the 

fine pulverization step must be finished before the particle classification step, otherwise there would be no fine 

powder to remove. Furthermore, Hitachi argues, the 

written description repeatedly distinguishes the act of 

fine pulverization conducted in the milling chamber of the 

apparatus from the particle classification performed in 

the classifier, and requires a high-speed flow of gas for the 

pulverization. Finally, Hitachi argues that Ohashi leads 

away from claim 4 by teaching that the pulverization 

should be conducted in a “non-oxidizing or inert gas” and 

oxygen is indisputably an oxidizing gas.
18 HITACHI METALS, LTD. v. ALLIANCE OF RARE-EARTH

The Alliance responds that the Board properly interpreted the specification. First, the Alliance argues, claim 

1 recites “a second pulverization step of finely pulverizing

the material alloy, . . . wherein said second pulverization 

step comprises a step of removing at least part of the fine 

powder,” id. col. 13 ll. 24–31 (emphasis added), and thus 

indicates that the particle classification (i.e., “remov[al]”) 

is part of the “second pulverization step.” Second, the

Alliance contends that the written description repeatedly 

describes “fine pulverization” as including a step of removing the fine powder. See, e.g., id. Abstract (“In the 

second pulverization step, easily oxidized super-fine 

powder . . . is removed . . . ”); id. col. 4 ll. 56–62 (“In the 

method according to the present invention, after a material alloy . . . is coarsely pulverized and before a fine 

pulverization step is finished, at least part of R-rich superfine powder . . . is removed. . . .”) (emphasis added).

We agree with Hitachi that the Board misconstrued 

claim 4. As an initial matter, the parties seem to agree 

that, as recited in claim 1, the fine pulverization and 

particle classification are sub-steps of the umbrella “second pulverization step.” They disagree only as to whether 

claim 4’s requirement of a high-speed flow of gas comprising oxygen pertains to the umbrella step or to the first 

sub-step. We agree with Hitachi that claim 4 requires the 

use of a high-speed flow of gas comprising oxygen for the 

first sub-step of claim 1—the fine pulverization—rather 

than the umbrella “second pulverization step.” 

The passages of the written description which the Alliance cite merely confirm that the particle classification 

step is a sub-step of the umbrella “second pulverization 

step,” which, as we noted above, the parties do not dispute. The issue is whether claim 4 requires a high-speed 

oxygen-containing gas for the umbrella step, or for the 

first sub-step. We conclude that it refers to the latter; and 

the passages relied on by the Alliance do not contradict 

that interpretation. 
HITACHI METALS, LTD. v. ALLIANCE OF RARE-EARTH 19

The written description explains that “[i]n the second 

pulverization step, the alloy is preferably finely pulverized using a high-speed flow of gas” containing oxygen, id. 

col. 3 ll. 27–30, and that “[t]he alloys may be finely pulverized using a jet mill,” id. col. 3 l. 46. Thus, it is clear 

that the high-speed gas is associated with the fine pulverization conducted in the jet mill. And the written description clearly distinguishes the jet milling apparatus from 

the particle classifier for performing the two distinct substeps—fine pulverization and particle classification, 

respectively. For example, the patent explains that 

“when a jet mill is used to perform fine pulverization 

under a high-speed flow of inert gas, a gas flow classifier . . . may be provided following the jet mill to enable 

effective removal of R-rich super-fine powder . . . . [A] jet 

mill is used for the fine pulverization.” Id. col. 5 ll. 23–30 

(emphases added). See also, e.g., id. col. 3 ll. 47–50 (“The 

alloys may be finely pulverized using a jet mill. In a 

preferred embodiment, a classifier is provided following 

the jet mill for classifying powder output from the jet 

mill.” (emphases added)); id. col. 6 ll. 55–57 (“Next, the 

coarsely pulverized powder . . . is finely pulverized (or 

milled) with a jet mill. To the jet mill used in this embodiment, a cyclone classifier is connected for removal of the 

fine powder.” (emphasis added)).

In fact, in every instance where the written description refers to pulverization using a high-speed flow of gas, 

it refers to the milling apparatus, i.e., “jet mill” or “pulverizer,” rather than the particle “classifier.” See, e.g., id. col. 

5 ll. 23–26 (“[W]hen a jet mill is used to perform the fine 

pulverization under a high-speed flow of inert gas, a gas 

flow classifier . . . may be provided following the jet mill to 

enable effective removal of R-rich super-fine powder . . . .” 

(emphasis added)); id. col. 6 l. 58–col. 7 l. 13 (discussing 

Figure 2, which shows the jet milling chamber, i.e., “pulverizer 14,” and the “classifier 16,” and explaining that 

the “material [is] pulverized with the pulverizer 14 
20 HITACHI METALS, LTD. v. ALLIANCE OF RARE-EARTH

[and] . . . classified with the cyclone classifier 16,” wherein 

“pulverizer 14 includes . . . nozzle fittings 28 for receiving 

nozzles through which an inert gas . . . is jet at high speed” 

(emphases added)); id. col. 8 ll. 15–20 (“The material to be 

pulverized fed into the pulverizer 14 is rolled up with 

high-speed jets of inert gas . . . and swirl[ed] together with 

high-speed gas flows inside the pulverizer 14. While 

swirling, the particles of material are finely milled by 

mutual collision with each other.” (emphases added)); id.

col. 10 l. 47–53 (referring to “the jet mill and the cyclone 

classifier connected to each other” and “a high speed flow 

gas for the jet mill.” (emphasis added)).

Thus, we reverse the Board’s construction of claim 4 

and conclude that it requires a high-speed flow of gas 

(claim 3) comprising oxygen (claim 4) for the “fine pulverization” that occurs in the first sub-step—for example, by

“pulverizer 14” shown in Figure 2. Under the correct

construction, the Board’s obviousness determination as to 

claim 4 must therefore be vacated. The Board premised 

its finding that Ohashi’s use of an air stream for particle 

classification (the second sub-step) taught the limitations 

of claim 4 on its interpretation that claim 4 requires a 

high-speed flow of gas for the umbrella step and that the 

two sub-steps constitute one continuous process under the 

umbrella step. Under that interpretation, the Board 

found that Ohashi’s disclosure of a high-speed flow of gas 

for the second sub-step constituted a teaching of gas for 

the entire umbrella step. But the correct construction 

precludes such a finding. Ohashi’s use of an air stream 

for particle classification only cannot meet the limitation 

of claim 4, which requires the use of a high-speed flow of 

gas comprising oxygen for fine pulverization. 

Therefore, because we reverse the Board’s claim construction, we vacate its obviousness determination as to 

claim 4 and remand for further consideration under the 

proper construction. We note that, on appeal, Hitachi did 

not argue claim 3 separately from claim 1, as it did for 
HITACHI METALS, LTD. v. ALLIANCE OF RARE-EARTH 21

claim 4. However, our conclusion with respect to the 

construction of claim 4 necessarily raises a question with 

respect to the construction and obviousness of claim 3. 

Thus, because we reverse the Board’s construction of 

claim 4, we also vacate its obviousness determination as 

to claim 3. 

We also suggest that, on remand, the Board consider 

Hitachi’s argument that Ohashi teaches away from the 

invention of claim 4 because Ohashi teaches that the

pulverization should be conducted in a “non-oxidizing or 

inert gas,” and oxygen, even under the Board’s definition 

of “oxidizing gas,” see, e.g., ’765 Decision, 2016 Pat. App. 

LEXIS 1083, at *21–22, is undeniably an oxidizing gas. 

In fact, the written description explains that oxygen is 

employed to intentionally oxidize the alloy and thus 

“control[] . . . the oxygen content of the finely pulverized 

alloy powder.” ’765 patent col. 9 ll. 30 (“The finely pulverized powder particles are coated with an oxide layer as 

described above.” (emphasis added)). 

Although Hitachi raised that argument before the 

Board, the Board’s explanation in rejecting it was seemingly non-responsive. See ’765 Decision, 2016 Pat. App. 

LEXIS 1083, at *38–39. In fact, the Alliance acknowledged during oral argument that the Board did not address Hitachi’s argument and asserted that, if we reverse 

the Board’s claim construction, we should remand for the 

issue to be decided by the Board. Oral argument at 

18:30–19:50, Hitachi Metals, Ltd. v. All. of Rare-Earth 

Permanent Magnet Indus., Nos. 16-1824, -1825 (Fed. Cir. 

June 8, 2017) (“At APPX53 is where the Board addresses 

the argument and doesn’t reach it.”), available 

at http://oralarguments.cafc.uscourts.gov/default.aspx?fl=

2016-1824.mp3. 

C. Obviousness over Ohashi, Hasegawa, and Yamamoto

The Board concluded that dependent claims 11 and 12 

would have been obvious over Ohashi, Hasegawa, and 
22 HITACHI METALS, LTD. v. ALLIANCE OF RARE-EARTH

Yamamoto. Hitachi makes the same arguments regarding the combinability of Ohashi and Hasegawa with 

Yamamoto that it asserts in connection with the ’385 

patent, as discussed above. Thus, we affirm the Board’s 

obviousness determinations as to claims 11 and 12 for the 

same reasons we stated above. 

In sum, we affirm the Board’s conclusion that claims 

1, 5, and 6 of the ’385 patent would have been obvious 

over Ohashi, Hasegawa, or He and Yamamoto, and that 

claim 1 was anticipated by He. We also affirm the Board’s 

conclusion that claims 1, 2, 14, and 16 of the ’765 patent 

would have been obvious over Ohashi and Hasegawa and 

that claims 11 and 12 would have been obvious over 

Ohashi, Hasegawa, and Yamamoto. However, we reverse 

the Board’s construction of claim 4 of the ’765 patent and 

thus vacate its obviousness determination as to claims 3 

and 4 and remand for further consideration consistent 

with this opinion. 

CONCLUSION

We have considered the remaining arguments but 

find them to be unpersuasive. For the foregoing reasons, 

we affirm-in-part and vacate-in-part the decision of the 

Board and remand for further consideration consistent 

with this opinion. 

AFFIRMED-IN-PART, VACATED-IN-PART, AND 

REMANDED 

COSTS

No costs