NOTE: This disposition is nonprecedential. 

United States Court of Appeals 

for the Federal Circuit 

__________________________ 

(Reexamination No. 95/001,168) 

FLUOR TEC, CORP., 

Appellant, 

v. 

DAVID J. KAPPOS, DIRECTOR, 

UNITED STATES PATENT AND TRADEMARK 

OFFICE, 

Appellee, 

AND 

LUMMUS TECHNOLOGY, INC., 

Appellee. 

__________________________ 

2012-1295 

__________________________ 

Appeal from the United States Patent and Trademark 

Office, Board of Patent Appeals and Interferences. 

__________________________ 

Decided: December 11, 2012 

__________________________ 

ROBERT D. FISH, Fish & Associates, PC, of Irvine, 

California, argued for appellant. With him on the brief 

was MEI TSANG. 
FLUOR TEC v. KAPPOS 2

 RAYMOND T. CHEN, Solicitor, United States Patent 

and Trademark Office, of Arlington, Virginia, argued for 

appellee, United States Patent and Trademark Office. 

With him on the brief were AMY J. NELSON and KRISTI 

L.R. SAWERT, Associate Solicitors. 

JEFFREY S. BERGMAN, Osha Liang LLP, of Houston, 

Texas, argued for appellee, Lummus Technology, Inc. 

__________________________ 

Before LOURIE, BRYSON, and WALLACH, Circuit Judges. 

LOURIE, Circuit Judge.

Fluor Tec, Corp. (“Fluor”) appeals from the decision of 

the Board of Patent Appeals and Interferences (the 

“Board”) in an inter partes reexamination affirming the 

Examiner’s decision not to reject claims 1–9, 11, 13, 25–

29, 31, 33, 37–47, 55, 56, and 58 of U.S. Patent 6,712,880 

(the “’880 patent”) owned by Lummus Technology, Inc. 

(“Lummus”). See Fluor Tec, Corp. v. Patent of Lummus 

Tech. Inc., No. 2011-013099 (B.P.A.I. Dec. 15, 2011) 

(“Board Decision”). Because substantial evidence supports the Board’s conclusion that the claimed invention 

would not have been obvious in view of the cited prior art, 

we affirm. 

BACKGROUND

This appeal arises from an inter partes reexamination 

of the ’880 patent in the U.S. Patent and Trademark 

Office (the “PTO”), assigned Patent Reexamination Control Number 95/001,168, which was initiated by third 

party requester Fluor under 35 U.S.C. § 311 and 37 

C.F.R. § 1.913. 

The ’880 patent is directed to cryogenic processes for 

separating multi-component gaseous hydrocarbon 
3 FLUOR TEC v. KAPPOS

streams to recover both gaseous and liquid compounds 

using a high pressure absorber. ’880 patent col.1 ll.10–15. 

The abridged claim 1 recited below, as amended during 

the reexamination proceeding, is representative of the 

claimed elements in dispute: 

1. A process for separating a heavy key component from an inlet gas stream containing a mixture of methane, C2 compounds, C3 compounds, 

and heavier compounds, comprising the following 

steps: 

(a) at least partially condensing and separating the inlet gas into a first liquid stream 

and a first vapor stream; 

(b) expanding at least a portion of the first 

liquid stream, at least a portion of which 

is then designated as a first fractionation 

feed stream; 

(c) supplying a fractionation column the first 

fractionation feed stream and a second 

fractionation feed stream, the fractionation column produces a fractionation overhead vapor stream and a fractionation 

bottom stream; 

(d) expanding at least a portion of the first 

vapor stream, such expanded portion then 

designated as an expanded vapor stream; 

(e) supplying an absorber the expanded vapor 

stream and an absorber feed stream, the 

absorber produces an absorber overhead 

stream and an absorber bottom stream, 

the absorber having an absorber pressure 

that is substantially greater than and at a 
FLUOR TEC v. KAPPOS 4

predetermined differential pressure from 

a fractionation column pressure; . . . 

J.A. 325–326 (bracketing and underlining showing 

changes relative to the original patent claim omitted). 

Figure 1, reproduced below, depicts a flow diagram of 

a separation process according to the ’880 patent: 

’880 patent fig. 1. 

Relevant to the issues argued in this appeal, Lummus’s separation apparatus is a two-column system that 

includes an absorber column [18] and a downstream 

fractionation column [22], wherein the absorber column is 

operated at a pressure substantially greater than the 

fractionation column. ’880 patent col.6 ll.52–60, col.3 

ll.48–54. Inlet gas [40] is first cooled or condensed in heat 

exchanger [12] and separated in separator [14] into first 
5 FLUOR TEC v. KAPPOS

liquid stream [44] and first vapor stream [42]. Id. col.7 

ll.18–27. The first liquid stream [44] is expanded in 

expander [24], heated in exchanger [12], and supplied to a 

middle tray of fractionation column [22] as first fractionation feed stream [58]. Id. col.7 ll.31–35. A portion of first 

liquid stream [44] may be fed to overhead exchanger [20], 

as well as exchanger [12], before being supplied to fractionation column [22]. Id. col.8 ll.5–11. The first vapor 

stream [42] is expanded in turboexpander [16] to the 

operating pressure of absorber [18]. Id. col.7 ll.29–31. 

The expanded first vapor stream [42a] is then fed into the 

lower end of absorber [18]. Id. col.7 ll.34–36. In the 

absorber, heavier compounds in the vapor stream are 

absorbed by the falling liquid stream to produce absorber 

bottom stream [45], and lighter compounds rise to the top 

of the column to produce absorber overhead stream [46]. 

Id. col.7 ll.50–59. Absorber bottom stream [45] is cooled 

(condensed) in exchangers [20] and [12], and fed into the 

middle of fractionation column [22] as second fractionation feed stream [48]. Id. col.7 ll.60–62, col.8 ll.17–21. 

In requesting reexamination, Fluor relied on International Patent Publication Number WO 02/14763 of Mak 

(the “Mak application”) as evidence of unpatentability. 

The Mak application discloses gas processing methods 

and configurations suitable for the recovery of propane or 

ethane that include an absorber and a fractionation 

column where the absorber is operated at a pressure 

higher than the fractionation column. Mak Appl. 2–3. 

The Mak application discloses two different configurations for gas separation, which depend on the pressure of 

the feed gas. One configuration, designed for use with 

low-pressure feed gas, does not involve expanding the first 

vapor stream, and is depicted in a flow diagram in Figure 

5, reproduced below: 
FLUOR TEC v. KAPPOS 6

Mak Appl. fig. 5. 

In this low-pressure design, the feed gas [1] is separated in separator [101] into a liquid portion [5] and a 

gaseous portion [2]. Id. at 8. The liquid portion [5] is 

expanded in Joules-Thompson valve [115] and fed directly 

into the fractionation column [106], and the gaseous 

portion [2] is cooled in heat exchanger [100] and fed into 

absorber [103] without expansion in a turboexpander. Id. 

The absorber overhead stream [9] is heated in exchanger 

[100] and fed into the gas pipeline without recompression, 

and the absorber bottom stream [7] is expanded in JoulesThompson valve [104], which reduces the pressure and 

temperature, then heated in exchanger [105] and fed into 

the top of fractionation column [106]. Id. 

The other configuration disclosed in the Mak application, designed for use with high-pressure feed gas, is 

depicted in a flow diagram in Figure 2, reproduced below: 
7 FLUOR TEC v. KAPPOS

Mak Appl. fig. 2. 

In this high-pressure design, the feed gas [1], [2] is 

cooled in heat exchanger [100] and separated in separator 

[101] into a liquid portion [5] that is fed into the upper 

end of absorber [103], and a gaseous portion [4] that is 

expanded in turboexpander [102] and fed into a lower 

section of absorber [103]. Id. at 6. The absorber bottom 

stream [7] is expanded in Joules-Thompson valve [104], 

which lowers the pressure and significantly cools the 

stream, then heated in exchangers [100] and [105] and 

then fed into the top of fractionation column [106]. Id. 

During reexamination, the Examiner rejected some of 

the patent claims as anticipated under 35 U.S.C. § 102(e) 

by the Mak application, and some of the claims as obvious 

under 35 U.S.C. § 103 in view of the Mak application. 

Thereafter, Lummus amended the independent claims to 

incorporate limitations from the dependent claims. 

Specifically, claim 1 was amended as excerpted above. 

Following the amendment, the Examiner withdrew the 

rejections of the claims in view of the Mak application. In 

particular, the Examiner found that the vapor stream in 

Mak’s low-pressure configuration (i.e., stream [2], [6] in 

Figure 5) is not expanded prior to entering the absorber, 
FLUOR TEC v. KAPPOS 8

as required by the claims. Right of Appeal Notice dated 

Jan. 20, 2011 in Control No. 95/001,168, 20–21. Further, 

the Examiner noted that, according to Lummus’s 

amended claims, the first fractionation feed stream in the 

’880 patent has the same chemical composition as the first 

liquid stream, which is merely renamed after being 

warmed in the heat exchangers en route to the fractionation column. Id. at 14–15. In contrast, the first liquid 

stream in Mak’s high-pressure configuration (i.e., stream 

[5] in Figure 2) is initially fed to the absorber, where it 

undergoes chemical processing, and it is the chemically 

altered absorber bottom stream that is fed into the fractionation column as the first fractionation feed stream. 

Id. at 15–16. 

Fluor then appealed to the Board under 35 U.S.C. § 

134(c). The Board affirmed the Examiner’s finding that 

the Mak application failed to anticipate the claims, and 

Fluor does not challenge that holding on appeal. See

Board Decision at 12. The Board, like the Examiner, also 

found that it would not have been obvious to add an 

expander to the low-pressure configuration taught by the 

Mak application and depicted in Figure 5 because that 

system was specifically designed and labeled not to include turboexpansion. Id. at 12–13. The Board also 

concluded that the Examiner was correct in finding that 

there was no motivation for a skilled artisan to modify the 

high-pressure configuration taught by Mak and depicted 

in Figure 2 by rerouting the liquid stream to the fractionation column. Id. at 13. Accordingly, the Board 

affirmed the Examiner’s decision not to reject the claims. 

Fluor timely appealed. We have jurisdiction pursuant 

to 28 U.S.C. § 1295(a)(4)(A). 
9 FLUOR TEC v. KAPPOS

DISCUSSION

A claim is invalid for obviousness if, to one of ordinary 

skill in the pertinent art, “the differences between the 

subject matter sought to be patented and the prior art are 

such that the subject matter as a whole would have been 

obvious at the time the invention was made.” 35 U.S.C. 

§ 103(a) (2006); see also KSR Int’l Co. v. Teleflex Inc., 550 

U.S. 398, 406–07 (2007). Obviousness is a legal conclusion based on underlying factual findings. In re Kao, 639 

F.3d 1057, 1065 (Fed. Cir. 2011). We review the Board’s 

legal conclusions de novo and its factual determinations 

for substantial evidence. In re Am. Acad. Sci. Tech. Ctr., 

367 F.3d 1359, 1363 (Fed. Cir. 2004). Substantial evidence means “such relevant evidence as a reasonable 

mind might accept as adequate to support a conclusion.” 

Consol. Edison Co. v. Nat’l Labor Relations Bd., 305 U.S. 

197, 229 (1938). 

I. 

The claims of the ’880 patent require either “expanding” or an “expansion means” for expanding at least a 

portion of the first vapor stream, which the specification 

discloses are to “be effectuated with a turbo-expander, 

Joules-Thompson expansion valves, a liquid expander, a 

gas or vapor expander or the like.” J.A. 325–326; ’880 

patent col.6 ll.35–39. Fluor contends that the Board 

incorrectly determined that it would not have been obvious to add an expander to the low-pressure configuration 

depicted in Figure 5 of the Mak application. Fluor argues 

that it would have been a mere design choice for a skilled 

artisan to add an expander when utilizing Mak’s lowpressure system with a high-pressure feed gas in order to 

improve the efficiency of the absorber, since the need to 

match the feed gas pressure with the absorber pressure 
FLUOR TEC v. KAPPOS 10

was well-known in the prior art.1 We disagree because 

substantial evidence supports the Board’s factual findings 

underlying its conclusion that the claims would not have 

been obvious. 

The system depicted in Figure 5 of the Mak application does not include expanding at least a portion of the 

first vapor stream as required by the claims; rather, vapor 

stream [2], [6] is fed into absorber [103] after cooling in 

heat exchanger [100], but without passing through an 

expander. Indeed, Mak’s low feed pressure configuration 

specifically excludes an expander: Figure 5 is expressly 

labeled as a “No Turboexpansion Design,” and the Mak 

specification recites (i) that “[t]he gaseous portion of [2] is 

cooled in a heat exchanger [100] and the cooled gaseous 

portion [6] is then fed into absorber [103] without expansion in a turboexpander,” Mak Appl. 8 (emphasis added); 

(ii) that “Figure 5 is a . . . configuration for a gas processing plant without turboexpander,” id. at 4 (emphasis 

 1 To support its argument, Fluor relies, in part, on 

U.S. Patent 4,657,571 issued to Gazzi (“Gazzi”), which is 

cited in the background section of the ’880 patent, but is 

not incorporated by reference into the patent specification 

or part of the prosecution history of the reexamination 

application. Fluor admits that Gazzi was never referenced in arguments to the Examiner or the Board and 

was not part of the administrative record considered by 

the Board, but nevertheless contends that it was within 

the knowledge of a person of ordinary skill in the art and 

therefore the Board’s failure to consider it warrants 

vacating and remanding the Board’s decision. Appellant 

Reply. Br. 9. However, because 35 U.S.C. § 144 provides 

that we “review the decision from which an appeal is 

taken on the record before the [PTO],” Gazzi is not properly before us for consideration on appeal. In re Watts, 354 F.3d 1362, 1367 (Fed. Cir. 2004) (“[R]eview of the 

Board’s decision is confined to the ‘four corners’ of that 

record.”). 
11 FLUOR TEC v. KAPPOS

added); and (iii) that “the feed gas is fed into the absorber 

without passing through a turboexpander,” id. at 8 (emphasis added). 

We agree with the Board’s determination that it 

would not have been obvious to modify Mak’s disclosure to 

add an expander. See DePuy Spine, Inc. v. Medtronic 

Sofamor Danek, Inc., 567 F.3d 1314, 1326 (Fed. Cir. 2009) 

(“An inference of nonobviousness is especially strong 

where the prior art’s teachings undermine the very reason 

being proffered as to why a person of ordinary skill would 

have combined the known elements.”). The Mak application discloses two different configurations, one designed 

for high-pressure feed gas and one designed for lowpressure feed gas, and that Mak specifically discusses the 

advantages of the “no turboexpander design” for lowpressure feed gas. See Mak Appl. 8–9. In Mak’s system, 

depicted in Figure 5, the gaseous portion is cooled in a 

heat exchanger before being fed into the absorber, but if 

high-pressure feed gas could be accommodated simply by 

adding an expander to the low-pressure configuration, 

then there would be no need for the separate highpressure configuration. See In re Gal, 980 F.2d 717, 719 

(Fed. Cir. 1992) (holding that different structure to 

achieve different purpose was not an obvious design 

choice). Adding an expander to Mak’s low-pressure 

configuration is not simply a design choice that one would 

employ. 

Moreover, a skilled artisan desiring to utilize a highpressure feed gas would have been directed to follow the 

alternative systems disclosed in the Mak application that 

are specifically designed to accommodate a high-pressure 

feed gas, rather than attempt to modify Mak’s lowpressure configuration. See In re Gurley, 27 F.3d 551, 553 

(Fed. Cir. 1994) (a reference teaches away “when a person 

of ordinary skill, upon reading the reference . . . would be 
FLUOR TEC v. KAPPOS 12

led in a direction divergent from the path that was taken 

by the applicant”). Accordingly, viewing the teachings of 

the Mak application as a whole, a skilled artisan would 

not have been motivated to add an expander to the lowpressure configuration depicted in Figure 5 to arrive at 

the claimed invention. Because the Board’s fact-finding is 

supported by substantial evidence, we affirm its conclusion of nonobviousness. In re Jolley, 308 F.3d 1317, 1320 

(Fed. Cir. 2002). 

II. 

The claims of the ’880 patent also require that the 

inlet gas is separated into a first liquid stream and a first 

vapor stream, and that at least a portion of the first liquid 

stream is designated as a first fractionation feed stream, 

which is supplied to a fractionation column. J.A. 325–

326. 

Fluor contends that the Board incorrectly determined 

that it would not have been obvious to modify the highpressure configuration depicted in Figure 2 of the Mak 

application by rerouting the first liquid stream [5]—

produced upon initial separation of feed gas [1], [2] in 

separator [101]—to the fractionation column [106] instead 

of to absorber [103] as disclosed. Fluor argues that a 

skilled artisan would have routed the liquid phase differently depending on the composition of the feed gas itself, 

i.e., whether it was rich or lean.2 Fluor asserts that it 

would have been obvious to reroute the liquid phase to the 

 2 A lean gas stream is one that contains a higher 

proportion of lighter hydrocarbons, such as methane (C1) 

and ethane (C2), and a lower percentage of heavier hydrocarbons, such as propane (C3) and butane (C4). In contrast, a rich gas stream is one that contains a lower 

proportion of lighter hydrocarbons and a higher proportion of heavier hydrocarbon components. 
13 FLUOR TEC v. KAPPOS

fractionation column as claimed, rather than to the absorber column as described in Mak’s high-pressure configuration, when the feed gas is rich because that would 

provide a more efficient separation in the system depicted 

in Figure 2, which is specifically designed for lean feed 

streams. We again disagree because substantial evidence 

supports the Board’s factual findings underlying its 

conclusion that the claims would not have been obvious. 

First, in the system depicted in Figure 2 of the Mak 

application, the liquid stream [5] is fed into the absorber 

[103] and undergoes chemical processing in the absorber, 

by interaction with gas stream [6] and reflux stream [19], 

to produce a liquid absorber bottom stream [7]. Mak 

Appl. 6, fig. 2. This chemically altered absorber bottom 

stream is subsequently expanded in Joules-Thompson 

valve [104], heated in exchangers [100] and [105], and 

then fed into fractionation column [106]. Id. In contrast, 

Lummus’s claims require that the expanded liquid stream 

be supplied directly to the fractionation column as a first 

fractionation feed stream without further chemical processing. The ’880 patent specification discloses that, with 

reference to Figure 1, after the feed gas is separated in 

separator [12], “[t]he first liquid stream [44] is expanded 

in expander [24] and then supplied to front end exchanger 

[12] and warmed . . . then supplied to a mid-column feed 

tray of fractionation column [22] as a first fractionation 

feed stream [58].” ’880 patent col.7 ll.31–35. 

Second, Lummus’s claims at issue here are not limited 

only to a rich feed gas, but encompass any hydrocarbon 

stream. See, e.g., claim 1 (“inlet gas stream containing a 

mixture of methane, C2 compounds, C3 compounds, and 

heavier compounds”); see also ’880 patent abstract, col.1 

ll.11–15, col.5 l.65–col.6 l.16. Moreover, neither the 

claimed invention nor the Mak application discloses or 

suggests that the mixture of hydrocarbons in the feed gas 
FLUOR TEC v. KAPPOS 14

should have a direct bearing on the choice of which process should be employed for separation; on the contrary, 

the disclosure in Mak emphasizes that the choice of 

configuration should depend on the pressure of the feed 

gas, not the composition. Mak Appl. 3, 6, 8, 10–11. 

Finally, Fluor has provided no evidence or rationale to 

support its proposition that a skilled artisan would have 

been motivated to substantially modify Mak’s highpressure configuration by rerouting the first liquid stream 

depending on the composition of the feed gas. KSR, 550 

U.S. at 418 (requiring “some articulated reasoning with 

some rational underpinning to support the legal conclusion of obviousness” (quoting In re Kahn, 441 F.3d 977, 

988 (Fed. Cir. 2006))); see also Mintz v. Dietz & Watson, 

Inc., 679 F.3d 1372, 1377 (Fed. Cir. 2012) (obviousness 

determination improper where “little more than an invocation of the words ‘common sense’ (without any record 

support showing that this knowledge would reside in the 

ordinarily skilled artisan)”). Therefore, again viewing the 

teachings of the Mak application as a whole, a skilled 

artisan would not have been motivated to modify the 

high-pressure configuration depicted in Figure 2 by 

rerouting the liquid stream to arrive at the claimed 

invention. Because the Board’s fact-finding is supported 

by substantial evidence, we affirm its conclusion of 

nonobviousness. Jolley, 308 F.3d at 1320. 

CONCLUSION

We have considered Fluor’s remaining arguments and 

find them unpersuasive. The Board’s judgment is affirmed. 

AFFIRMED