Case: 20-1858 Document: 42 Page: 1 Filed: 03/10/2021
NOTE: This disposition is nonprecedential.
United States Court of Appeals
for the Federal Circuit
______________________
NEAPCO DRIVELINES LLC,
Appellant
v.
AMERICAN AXLE & MANUFACTURING, INC.,
Appellee
______________________
2020-1858
______________________
Appeal from the United States Patent and Trademark
Office, Patent Trial and Appeal Board in No. IPR2018-
01761.
______________________
Decided: March 10, 2021
______________________
DENNIS J. ABDELNOUR, Honigman LLP, Chicago, IL, ar-
gued for appellant. Also represented by J. MICHAEL
HUGET, SARAH E. WAIDELICH, Ann Arbor, MI.
ROBERT KAPPERS, Steptoe & Johnson LLP, Chicago, IL,
argued for appellee. Also represented by JOHN LLOYD
ABRAMIC, KATHERINE H. JOHNSON, JAMES RICHARD
NUTTALL.
______________________
Case: 20-1858 Document: 42 Page: 2 Filed: 03/10/2021
2 NEAPCO DRIVELINES LLC v.
AMERICAN AXLE & MANUFACTURING
Before DYK, MOORE, and REYNA, Circuit Judges.
MOORE, Circuit Judge.
Neapco appeals a Patent Trial and Appeal Board final
written decision finding claim 11 of U.S. Patent No.
5,772,520 anticipated by Burton 1 and holding claim 12
would have been obvious over Burton in combination with
other references. We affirm.
BACKGROUND
The ’520 patent discloses a “vented slip joint assembly.”
’520 patent at Abstract. A slip joint is a coupling between
two shafts of a vehicle’s driveline. See id. at 1:12–15. One
shaft has external splines, which are gear-like teeth, and
the other shaft has an internally “splined bore” that re-
ceives the external splines of the first shaft. Id.; see also
id. at Fig. 3. The “mating” of the splines ensures that the
shafts rotate together while allowing axial movement, i.e.,
slip.
To prevent entry of contaminants, a slip joint assembly
includes seals at either end of the splined bore. Id. at 1:19–
20. One issue with sealing the slip joint, however, is that
axial movement between the shafts “compresses air within
the splined bore” (the first cavity) and “between the splined
shaft and the seals” (the second cavity). Id. at 1:15–22.
Prior art addressed this issue by adding a hole in the cap,
which is the seal at the end of the first cavity opposite the
splined shaft. Id. at 1:23–32. But this hole permits entry
of contaminants and vents the first cavity only. Id. The
objective of the ’520 patent is to provide a slip joint assem-
bly that vents the second cavity and does not allow entry of
1 U.S. Patent No. 5,655,968.
Case: 20-1858 Document: 42 Page: 3 Filed: 03/10/2021
NEAPCO DRIVELINES LLC v. 3
AMERICAN AXLE & MANUFACTURING
contaminants. See id. at 1:33–46. Claim 11 is representa-
tive: 2
11. A method of venting a slip joint assembly com-
prising[:]
providing a first shaft having a first end
with an externally splined portion;
providing a second shaft having a closed
first end with an internally splined portion
defining a first cavity therein, the second
shaft drivably connected to the first end of
the first shaft;
providing a seal to sealingly engage the
first and second shafts to create a second
cavity therebetween defined by the seal
and the first and second shafts; and
providing a vent in the first shaft having a
first end in fluid communication with the
second cavity and a second end in fluid
communication outside the first and second
cavities.
American Axle petitioned for inter partes review of the
’520 patent in view of Burton. The Board concluded that
Burton anticipates claim 11 and claim 12 would have been
obvious over Burton in combination with other prior art.
Neapco appeals. We have jurisdiction under 28 U.S.C.
§ 1295(a)(4)(A).
DISCUSSION
Neapco raises two issues. First, it argues the preamble
of claim 11 limits the claim to slip joints that vent to an
2 We treat claim 11 as representative because
Neapco does not present any separate arguments concern-
ing claim 12.
Case: 20-1858 Document: 42 Page: 4 Filed: 03/10/2021
4 NEAPCO DRIVELINES LLC v.
AMERICAN AXLE & MANUFACTURING
external space (outside of the entire slip joint assembly).
Second, Neapco argues substantial evidence does not sup-
port the Board’s finding that Burton discloses the “provid-
ing a vent” limitation. We address each issue in turn.
I.
We review de novo the Board’s claim construction and
any supporting determinations based on intrinsic evidence.
Personalized Media Commc’ns, LLC v. Apple Inc., 952 F.3d
1336, 1339 (Fed. Cir. 2020). “Generally, a preamble is not
limiting.” Summit 6, LLC v. Samsung Elecs. Co., 802 F.3d
1283, 1292 (Fed. Cir. 2015). A preamble is not limiting, for
example, if the patentee “defines a structurally complete
invention in the claim body and uses the preamble only to
state a purpose or intended use for the invention.” Cata-
lina Mktg. Int’l, Inc. v. Coolsavings.com, Inc., 289 F.3d 801,
808 (Fed. Cir. 2002). We have, however, identified several
exceptions to the general rule that a preamble is not limit-
ing. Relevant here, a preamble is limiting if it recites “ad-
ditional structure or steps underscored as important by the
specification,” is “essential to understand limitations or
terms in the claim body,” or provides necessary structure
absent from the claim body. Id. at 808–09.
Neapco argues the preamble, “[a] method of venting a
slip joint assembly,” is limiting because it recites venting
the entire slip joint assembly, which is what the specifica-
tion “from top to bottom is concerned with.” Appellant’s Br.
at 34. Neapco further argues the claim body is structurally
incomplete because the “providing a vent” limitation iden-
tifies neither the object being vented nor the destination of
the venting. For support, Neapco juxtaposes claim 6, which
specifically recites the vent destination is “the driveshaft.”
According to Neapco, the preamble cures this deficiency by
clarifying that the vented object is the slip joint assembly
and the vent destination is external thereto. Thus, the ar-
gument goes, the preamble is essential to understand the
“providing a vent” limitation.
Case: 20-1858 Document: 42 Page: 5 Filed: 03/10/2021
NEAPCO DRIVELINES LLC v. 5
AMERICAN AXLE & MANUFACTURING
American Axle responds that the “providing a vent”
limitation is clear as to the object and destination of the
venting. American Axle also points out that Neapco never
cited the preamble before the Board to support its proposed
construction of “vent.” And American Axle argues the spec-
ification neither stresses the importance of external vent-
ing nor conveys an intent to exclude sealed slip joints.
We see no error in the Board’s construction. The Board
correctly determined that the preamble of claim 11 is not
limiting. The claim body defines a structurally complete
invention, and the preamble is not essential to understand
any claim terms. Contrary to Neapco’s argument, the
“providing a vent” limitation recites the vented object (i.e.,
“the second cavity”) and the vent destination (i.e., “outside
the first and second cavities”). Neapco asserts this is not
specific enough, but the preamble phrase “[a] method of
venting a slip joint assembly” does not provide additional
specificity. Indeed, Neapco did not cite the preamble to
support its proposed constructions of “vent” before the
Board. J.A. 879–84, 1043–48. That claim 6 requires vent-
ing to “the driveshaft” shows Neapco knew how to recite
the vent destination more narrowly, which suggests the
broader language in claim 11 was intentional. Neapco has,
therefore, not shown that the preamble informs the mean-
ing of, or provides necessary structure to, the claim body.
Nor does the preamble recite “additional structure or
steps underscored as important by the specification.” Cat-
alina, 289 F.3d at 808. Neapco is correct that the specifi-
cation identifies a problem unique to external venting
(“ingress of contaminants”), touts a benefit of external
venting (“less resistance”), and describes every embodi-
ment as having an external vent. See, e.g., ’520 patent at
1:30–32, 2:44–3:10, 3:19–23. Nonetheless, the specification
describes external vents merely as part of preferred and al-
ternative embodiments. See id. at 2:44–3:10. And alt-
hough the specification makes clear that venting is
required, it does not indicate that the venting must be
Case: 20-1858 Document: 42 Page: 6 Filed: 03/10/2021
6 NEAPCO DRIVELINES LLC v.
AMERICAN AXLE & MANUFACTURING
external to the slip joint. We therefore agree with the
Board that the specification “does not underscore the im-
portance of venting outside the slip joint instead of venting
the cavities within the slip joint.” J.A. 14. Accordingly, we
hold the preamble does not limit claim 11 to externally
vented slip joints.
II.
Anticipation is a question of fact that we review for sub-
stantial evidence. In re Suitco Surface, Inc., 603 F.3d 1255,
1259 (Fed. Cir. 2010). Substantial evidence is “such rele-
vant evidence as a reasonable mind might accept as ade-
quate to support a conclusion.” Id. (quoting Consol. Edison
Co. v. NLRB, 305 U.S. 197, 229 (1938)).
Neapco argues Burton does not disclose claim 11’s
“providing a vent” limitation because there is no evidence
Burton’s passage 130 permits “escape of compressed air.”
The evidence instead shows, according to Neapco, that pas-
sage 130 merely facilitates air circulation between Burton’s
internal cavities and therefore does not relieve pressure.
American Axle responds that the Board’s construction of
“vent” encompasses air circulation between Burton’s inter-
nal cavities.
Burton discloses a slip joint assembly having a seal
(sealing sleeve 108), a first cavity (chamber 102), and a sec-
ond cavity (space 132):
J.A. 480 at 4:13–21, 4:30–40, Fig. 3. Passage 130 extends
through the studyoke (male splined shaft 90), providing
Case: 20-1858 Document: 42 Page: 7 Filed: 03/10/2021
NEAPCO DRIVELINES LLC v. 7
AMERICAN AXLE & MANUFACTURING
fluid communication between the second cavity and a space
outside the first and second cavities (chamber 124). Id.
Chamber 124 is internal to the slip joint assembly.
Substantial evidence supports the Board’s finding that
Burton discloses the “providing a vent” limitation. The
Board construed “vent” to mean “a passageway that per-
mits the escape of compressed air from a cavity.” J.A. 19–
20. Applying that construction, the Board found that Bur-
ton’s passage 130 is a “vent” because it permits compressed
air to escape from a cavity (space 132). J.A. 30–31. This
finding is supported by substantial evidence. Burton dis-
closes that “[w]hen the yokes 80 and 82 retract toward one
another, air moves from the space 132 through the pas-
sage[] 130.” J.A. 480 at 4:30–46. And Neapco concedes that
passage 130 permits airflow from space 132. See, e.g., Ap-
pellant’s Br. at 50 (“[A]ir and lubricant circulate back and
forth between chambers 102, 132, and 124, by way of bores
122 and 130.”).
Neapco nevertheless argues that airflow from Burton’s
space 132 is distinct from “escape of compressed air” be-
cause it does not relieve pressure. The Board, however, re-
jected Neapco’s proposal to inject a pressure relief
requirement into its construction, and Neapco does not ap-
peal that construction. J.A. 19–20. Moreover, Neapco and
its expert admitted that airflow from space 132 does in fact
relieve pressure. J.A. 2885 (Neapco’s expert testifying that
“[w]ithout the passage [130] the change in pressure would
be greater in [space] 132 than as opposed to with the pas-
sage”); J.A. 3962–63 at 43:17–44:2 (Neapco’s counsel agree-
ing that without venting to chamber 124, “the pressure in
[space 132] is going to go up more than it would with hav-
ing the chamber 124”). Accordingly, substantial evidence
supports the Board’s finding that Burton’s passage 130
meets the “providing a vent” limitation.
Case: 20-1858 Document: 42 Page: 8 Filed: 03/10/2021
8 NEAPCO DRIVELINES LLC v.
AMERICAN AXLE & MANUFACTURING
CONCLUSION
Because we hold the preamble of claim 11 is not limit-
ing and substantial evidence supports the Board’s finding
of anticipation, we affirm.
AFFIRMED