Snap-on wins claim construction argument at CAFC but still loses appeal

Snap-on challenged patents via IPR, lost, appealed, and then lost at the CAFC:



Snap-on Incorporated (Snap-on) appeals from the final
written decisions of the Patent Trial and Appeal
Board (Board) in the above-captioned inter partes review
proceedings (IPRs) that found certain claims of three of
Appellees’ patents to be nonobvious over prior art combinations
argued by Snap-on.



Of interest, Snap-on won on claim construction but lost
via the "substantial evidence" standard:


Snap-on also argues that the Board erred in “entirely
read[ing] out” the term “average” in its construction.
Snap-on Open. Br. 33. We agree. As a general matter, we
construe a claim term to take on its plain and ordinary
meaning to one of skill in the art when read in the context
of the specification and prosecution history. Wasica Fin.
GmbH v. Cont’l Auto. Sys., Inc., 853 F.3d 1272, 1282 (Fed.
Cir. 2017). Appellees’ own cited expert testimony states:
One of ordinary skill in the art in relation to the
patents in suit would have understood that the
term “average discharge current greater than or
equal to approximately 20 amps” as used in the
patents in suit referred primarily to the capability
of providing an average discharge current of approximately
20 amps, and that it included the operational
range of currents for battery packs for
hand held power tools.

J.A. 12336–37 (emphasis added). Thus, Appellees’ own
expert included the word “average” in his stated interpretation
of the 20-Amp Limitation.

Appellees nevertheless argue that omission of the
word “average” from the Board’s construction is supported
by evidence in the record showing that batteries were
commonly tested using “[c]onstant current discharge
tests” that held current constant while measuring voltage.
Resp. Br. 42 (citing J.A. 3898–99). While this may be
true, there is no indication in the specification4 that this
sort of testing should limit the plain and ordinary meaning
of “average,” which would include situations when
current rises above and dips below the 20-amp target so
long as the average discharge current over the entire
rated capacity is 20 amps or greater.
The specification references the 20-Amp Limitation in
only one place:
In some constructions, the battery pack 30 can
power various power tools (including a driver drill
300 and circular saw 305) having high discharge
current rates. For example, the battery pack 30
can supply an average discharge current that is
equal to or greater than approximately 20 A, and
can have an ampere-hour capacity of approximately
3.0 A-h.
J.A. 267, ’290 patent col. 10 ll. 20–26. Snap-on argues,
and Appellees do not dispute, that a battery pack discharges
current in bursts when used with a circular saw,
such that the current would swing above and below 20
amps. The fact that the phrase “average discharge current”
is only used in the portion of the specification describing
an “example” of embodiments that undisputedly
discharge current at levels that swing above and below 20
amps shows that the word “average” should take on its
ordinary meaning, especially given the Board’s obligation
to use the broadest reasonable construction in IPRs.
Cuozzo Speed Techs., LLC v. Lee, 136 S. Ct. 2131, 2142
(2016).
For the foregoing reasons, we hold that the correct
claim construction of the 20-Amp Limitation is: “the
battery cells, when configured together in a battery pack,
are capable of producing, on average, reasonably close to
20 amps of discharge current or greater over the course of
delivering their entire rated capacity.” Although the
Board erred in omitting the word “average” from its
construction, the Board’s fact findings regarding obviousness
are still supported by substantial evidence and the
Board’s legal determinations of obviousness are correct
under the proper claim construction.5 The harmless error
rule applies to appeals from the Board. See, e.g., In re
Watts, 354 F.3d 1362, 1369 (Fed. Cir. 2004). Re