Federal Circuit disposition — 23-2380

NOTE: This disposition is nonprecedential.
United States Court of Appeals
for the Federal Circuit
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IN RE: JOHN ROBERT BUTLER, STULLER, INC.,
Appellants
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2023-2380
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Appeal from the United States Patent and Trademark
Office, Patent Trial and Appeal Board in No. 16/891,541.
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Decided: September 17, 2025
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RONALD BENNETT FORD, JR., Roy Kiesel Ford Doody &
North, APLC, Baton Rouge, LA, argued for appellants.
Also represented by CHAD GRAND.
MONICA BARNES LATEEF, Office of the Solicitor, United
States Patent and Trademark Office, Alexandria, VA, ar-
gued for appellee Coke Morgan Stewart. Also represented
by AMY J. NELSON, MAUREEN DONOVAN QUELER.
______________________
Before PROST, LINN, and REYNA, Circuit Judges.
REYNA, Circuit Judge.
Appellants, John Robert Butler and Stuller, Inc., ap-
peal a final written decision of the U.S. Patent Trial and
Appeal Board affirming a patent examiner’s rejection of
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IN RE: BUTLER 2
claims 1–15 of U.S. Patent Application No. 16/891,541 for
lack of written description under 35 U.S.C. § 112(a). For
the reasons stated below, we affirm.
BACKGROUND
On June 3, 2020, Appellant John Robert Butler filed
U.S. Patent Application No. 16/891,541 (the “’541 applica-
tion”), which is assigned to Appellant Stuller, Inc. The ’541
application is a continuation of U.S. Patent Application
No. 14/945,230, which is a continuation of U.S. Patent Ap-
plication No. 13/224,116 (the “’116 application”). The ’541
application is directed to a hardened, corrosion-resistant
sterling silver alloy. ’541 application at 1. The ’541 appli-
cation explains that traditional sterling silver is relatively
soft and susceptible to corrosion or tarnishing. Id. at 1–2.
These characteristics can be disadvantageous in certain
jewelry-making applications. For example, the alloy’s soft-
ness may hinder stone setting and the formation of durable
hinges and clasps. Id. The ’541 application asserts that
various alloying elements—such as palladium and
tin—can be used in the art to improve tarnish resistance
and hardness of the sterling silver. Id. at 5. The ’541 ap-
plication purports to address the shortcomings of tradi-
tional sterling silver by incorporating such elements into
its alloy composition. Id. at 3–5.
Claims 1–15 of the ’541 application are at issue on ap-
peal. Claim 1, which is representative and dispositive of
the remaining claims, is shown below:1
1. A sterling silver comprising:
at least about 92.5 percent, by weight, silver,
and wherein said silver is alloyed with between
1 Because Claim 1 is the sole independent claim, the
patentability of the remaining dependent claims rises and
falls with it.
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IN RE: BUTLER 3
about 2.0 percent and about 3.7 percent copper by
weight, and between about 2.5 percent and about
3.3 percent palladium by weight, and tin and
wherein said sterling silver is free of germanium.
Id. at claim 1 (emphasis added). Relevant to this appeal,
the negative limitation “free of germanium” is claimed in
the ’541 application, but it was not claimed in the ’116 ap-
plication.
During the prosecution of the ’541 application, the ex-
aminer rejected claims 1–15 for lack of written description
support under 35 U.S.C. § 112(a), finding that the specifi-
cation of the ’116 application (the “original disclosure”)
lacked adequate support for the negative limitation “free of
germanium.” J.A. 178–83. Mr. Butler appealed the deci-
sion to the U.S. Patent Trial and Appeal Board (“Board”).
Mr. Butler argued that figure 1 of the original disclosure
illustrates a germanium-free sterling silver alloy because
it lists a preferred alloy composition without germanium,
as shown below:
’116 application, figure 1, at J.A. 71.
Mr. Butler also asserted that the original disclosure
identifies various advantages of the preferred alloy over a
well-known germanium-based, tarnish-resistant sterling
silver, Argentium. According to Mr. Butler, a skilled
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IN RE: BUTLER 4
artisan would have been aware of Argentium’s disad-
vantages despite its tarnish resistance. Mr. Butler con-
tended that, given this background knowledge and the
original disclosure’s discussion of a germanium-free alloy
that outperforms its germanium-containing counterpart, a
skilled artisan would have had “ample reason to omit ger-
manium from a tarnish resistant sterling alloy.” Ex Parte
John Robert Butler, No. 2022-002926, 2023 WL 4289547,
at *2 (P.T.A.B. June 29, 2023) (“Final Decision”). Mr. But-
ler maintained that this was sufficient to show possession
of the negative limitation.
The Board affirmed the examiner’s rejection. Id. at *3.
The Board observed that the preferred germanium-free al-
loy of figure 1 did not comprise the composition and per-
centage of elements recited in claim 1. The Board therefore
concluded that figure 1 disclosed an alloy that supported
only its illustrated composition, not the broader composi-
tion recited in claim 1. The Board further determined that
the original disclosure did not link any performance ad-
vantages of the claimed alloy to the absence of germanium,
and that Mr. Butler’s reliance on a skilled artisan’s
knowledge of Argentium’s drawbacks showed, at most, an
obvious variant, rather than possession of the fully claimed
scope.
Appellants timely appealed to this court. We have ju-
risdiction under 28 U.S.C. § 1295(a)(4)(A).
DISCUSSION
We review the Board’s legal determinations de novo
and its underlying factual findings for substantial evi-
dence. See Almirall, LLC v. Amneal Pharms. LLC, 28
F.4th 265, 271 (Fed. Cir. 2022). Substantial evidence is
“such relevant evidence as a reasonable mind might accept
as adequate to support a conclusion.” Consol. Edison Co.
v. NLRB, 305 U.S. 197, 229 (1938). Whether a claimed in-
vention is supported by an adequate written description is
a question of fact. Ariad Pharms., Inc. v. Eli Lilly &
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IN RE: BUTLER 5
Co., 598 F.3d 1336, 1351 (Fed. Cir. 2010) (en banc). A con-
tinuation application is entitled to the filing date of its par-
ent only if the earlier application provides written
description support for the claimed subject matter. Id.
Appellants raise one principal issue on appeal: whether
the original disclosure provides adequate written descrip-
tion support under 35 U.S.C. § 112(a) for the negative lim-
itation, “free of germanium,” recited in claim 1 of the ’541
application, noting that the ’541 application and ’116 appli-
cation have identical written descriptions and drawings.
Appellants’ Br. 3–5. Appellants specifically argue (1) that
the Board applied the wrong legal standard when as-
sessing the written description requirement and (2) that its
determination of lack of written description support is un-
supported by substantial evidence. Appellants’ Br. 5–6.
We disagree.
I.
The Board correctly articulated and applied the gov-
erning standard for written description inquiries. Final
Decision, 2023 WL 4289547, at *2–3 (citing Novartis
Pharms. Corp. v. Accord Healthcare, Inc., 38 F.4th 1013,
1016 (Fed. Cir. 2022)). As the Board noted, the written de-
scription requirement is satisfied if the patent specification
“reasonably convey[s] to those skilled in the art that the
inventor had possession of the claimed subject matter as of
the filing date.” Novartis, 38 F.4th at 1016 (quoting Ariad
Pharms., 598 F.3d at 1351). As it relates to negative limi-
tations, the specification need not recite the negative limi-
tation verbatim to satisfy the written description
requirement, but generally, there must be something in the
specification that “describes a reason to exclude the rele-
vant element.” Id. at 1017 (citation modified); see also San-
tarus, Inc. v. Par Pharm., Inc., 694 F.3d 1344, 1351
(Fed. Cir. 2012). The sufficiency of a disclosure is assessed
on a case-by-case basis. Vas-Cath Inc. v. Mahurkar, 935
F.2d 1555, 1562 (Fed. Cir. 1991).
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IN RE: BUTLER 6
In this case, the Board noted that the original disclo-
sure compares the corrosion performance of the preferred
alloy both to a germanium-containing alloy, Argentium (Al-
loy A), and to four other commercial alloys (Alloys B–E)
that lack germanium but “contain at least one element
other than germanium not recited in Appellant’s claims.”
See Final Decision, 2023 WL 4289547, at *2; see also ’116
application, figure 3, at J.A. 72. In doing so, the Board ob-
served that, because the disclosure shows the “superiority
of Appellant’s preferred alloy compared to alloys that do
not contain germanium, the results do not attribute the su-
periority to [the] lack of germanium.” Final Decision, 2023
WL 4289547, at *2. Appellants assert that this statement
demonstrates the Board required the original disclosure to
attribute certain advantages of the claimed invention as
due to the omission of germanium. Appellants’ Br. 20–22.
Appellants argue that such a requirement is improper be-
cause, under our precedent, if the specification “properly
describ[es] alternative features—without articulating ad-
vantages or disadvantages of each feature—[it] can consti-
tute a ‘reason to exclude.’” Inphi Corp. v. Netlist, Inc., 805
F.3d 1350, 1355 (Fed. Cir. 2015); see also Appellants’
Br. 20–22. We disagree.
The Board did not require that the original disclosure
attribute advantages of the claimed invention to the lack of
germanium in order to satisfy the written description re-
quirement. Rather, the Board merely recognized that the
original disclosure failed to do so. The Board did not err by
highlighting this deficiency, as it is well established that a
specification’s “discussion of disadvantages or alternatives”
may indicate a reason to exclude an element. Novartis, 38
F.4th at 1017. As explained below, the Board also rejected
Appellants’ assertion that a skilled artisan would have had
a reason to exclude germanium based on the original dis-
closure. Infra, Section II. Accordingly, the Board analyzed
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IN RE: BUTLER 7
the § 112 written description requirement under the cor-
rect legal standard for assessing negative limitations.2
II.
The Board’s conclusion that the negative limitation
lacks written description support in the original disclosure
is supported by substantial evidence. Following Inphi, we
emphasized that one “reason to exclude an element could
be found [if] the specification ‘distinguishes among’ the el-
ement and alternatives to it.” Novartis, 38 F.4th at 1016
(citing Inphi, 805 F.3d at 1357). As we have explained, the
“common denominator” of the examples where this court
has found a specification describes a reason to exclude a
relevant element is “disclosure of the element. That makes
sense because the hallmark of written description is disclo-
sure. Silence is generally not disclosure.” Novartis, 38
F.4th at 1017 (emphasis added) (citations and quotations
omitted).
Here, the original disclosure includes only one cursory
reference to the chemical symbol for germanium when de-
scribing the components of the comparative alloy
2 The Board noted that Appellants’ assertions that a
skilled artisan would recognize a reason to exclude germa-
nium amounted to an argument that the claimed “germa-
nium-free sterling silver . . . would have been an obvious
variant of Appellant’s originally-disclosed sterling silver
that is not disclosed as being free of germanium,” which is
insufficient to establish written description support under
our precedent. Final Decision, 2023 WL 4289547, at *3 (cit-
ing Lockwood v. Am. Airlines, Inc., 107 F.3d 1565, 1572
(Fed. Cir. 1997)). Rather, as we explained in Lockwood, a
skilled artisan demonstrates possession of the claimed in-
vention “by describing the invention,” not by describing
“that which makes [the claimed invention] obvious.” Lock-
wood, 107 F.3d at 1572.
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IN RE: BUTLER 8
Argentium. ’116 application at J.A. 68 (noting Argentium
has “the following composition: 92.7 percent Ag; 5.5 percent
Cu; and 1.8 percent Ge.”). The original disclosure other-
wise does not discuss this element. Novartis, 38 F.4th
at 1017 (“[T]he written description requirement cannot be
met through simple disregard of the presence or absence of
a limitation.”). For example, the original disclosure never
describes germanium itself as an alternative element,
much less distinguishes it from other elements included in
the claimed sterling silver composition. Instead, it de-
scribes a comparative alloy containing germanium, Argen-
tium, as an alternative to a preferred alloy that is different
from the sterling silver of claim 1. Moreover, as the Board
recognized, the original disclosure also compares the pre-
ferred alloy to four other commercial alloys that exclude
germanium, like the claimed sterling silver alloy. The orig-
inal disclosure then contends that the preferred alloy out-
performs these non-germanium-based alloys. As such, the
Board reasonably concluded that the comparison to various
alternative alloys neither distinguishes germanium nor
suggests the inventor intended to exclude or omit germa-
nium in the claimed invention.
While it is true that there are instances where “the
written description requirement [could] be satisfied despite
the specification’s silence” regarding a negative limitation,
here there is substantial evidence that Appellants do not
satisfy the requisite standard. Id. at 1018. That is, a pa-
tent owner may demonstrate a reason to exclude a limita-
tion if the patent owner can “establish that a particular
limitation would always be understood by skilled artisans
as being necessarily excluded from a particular claimed
method or apparatus if that limitation is not mentioned.”
Id. (emphasis added). Here, Appellant submitted an expert
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IN RE: BUTLER 9
declaration in support of his appeal before the Board.3
While the declaration states that the listing of elements of
the preferred alloy in figure 1 “appears to be comprehen-
sive,” it does not establish that a skilled artisan would al-
ways understand that germanium should be necessarily
excluded. J.A. 169. Thus, substantial evidence supports
the Board’s conclusion that the negative limitation lacks
explicit written description support.
In sum, although the ’116 application discloses a pre-
ferred alloy that does not list germanium, the Board rea-
sonably concluded that it does not provide a reason to
exclude germanium or otherwise reasonably convey posses-
sion of the claimed germanium-free alloy at its time of fil-
ing. Accordingly, we conclude that the Board applied the
correct legal standard in affirming the examiner’s rejection
and that its final written decision is supported by substan-
tial evidence.
CONCLUSION
We have considered Appellants’ remaining arguments
and find them unpersuasive. For the reasons provided, we
affirm the Board’s decision to sustain the examiner’s
3 Appellants assert that the Board ignored its expert
declaration and failed to consider the written description
question from the perspective of a skilled artisan. But this
is incorrect. The Board did not summarily dismiss “the
declaration, without an adequate explanation of why the
declaration failed to rebut the Board’s prima facie case of
inadequate description.” In re Alton, 76 F.3d 1168, 1174
(Fed. Cir. 1996). Rather, the Board acknowledged Appel-
lants’ expert declaration and the knowledge of a skilled ar-
tisan and found that it did not demonstrate possession of
the claimed germanium-free alloy. Final Decision, 2023
WL 4289547, at *1–3.
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IN RE: BUTLER 10
rejection of claims 1–15 of the ’541 application for lack of
written description under 35 U.S.C. § 112(a).
AFFIRMED
COSTS
Costs against Appellants.
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