Litigation over U.S. Patent No. 5,302,021, a patent with one claim

The single claim of U.S. Patent No. 5,302,021, which reads

A method of preventing the formation of an air pocket around
rotating blades positioned in a pitcher of a blender, the air pocket
being created from an air channel of a cross-sectional size defined
by a member associated with the blades, comprising the steps of
supplying a fluid into the pitcher, and positioning a plunger, having
a cross-sectional size approximating the cross-sectional size of the
member, adjacent to and above the rotating blades while
maintaining the plunger free of contact with the pitcher thereby
preventing the formation of an air pocket in the fluid around the
rotating blades.

generated a significantly more lengthy CAFC decision.

The applicant had worked to distinguish his invention from the prior art:
During prosecution, the applicant explained that the claimed method differed
from the prior art due to its preventative capability.

Much of the case centered around "disclaiming":

During the hearing, the court examined the prosecution history and
determined that the patentee expressly disclaimed any stirring operation that breaks up
or dislodges air pockets after they have begun to form, and limited the scope of the
claimed invention to positioning the plunger such that it prevents air pockets from
forming. The court construed claim 1 to exclude “stirring to disperse, dislodge, or break-
up an air pocket after it has begun to form.” The court also construed the term “plunger”
as a “device that can be inserted into a blender.”

This disclaimer arose from a determination about the claim preamble:

“a method of preventing the formation of an air pocket around the rotating blades positioned in a pitcher of a
blender” was necessary to give life, meaning and vitality to the body of the claim. See,
e.g., MBO Labs., Inc. v. Becton Dickson & Co., 474 F.3d 1323, 1330 (Fed. Cir. 2007); In
re Cruciferous Sprout Litig., 301 F.3d 1343, 1347 (Fed. Cir. 2007).

The district court was accused of inconsistency:

Vita- Mix contends that the district court erred in finding no direct infringement based, in part,
on applying to the accused device a claim construction inconsistent with its claim
construction order.

(...)

Vita- Mix argues on appeal that the exclusion of all stirring was a new construction, and
represents a change in the district court’s position. Vita-Mix argues that the original
claim construction order correctly construed the term “preventing the formation of an air
pocket” to exclude breaking up or dislodging already formed air pockets, and not to
exclude stirring for other reasons. Vita-Mix points out that the district court even noted
that the ’021 patent specification disclosed that the plunger could also be used to stir
the ingredients of the blender. Vita-Mix Corp. v. Basic Holdings, Inc., No. 1:06-cv-2622
(N.D. Ohio Sept. 10, 2007) (Claim Construction Order at 7).

The CAFC agreed with the patentee that the district court had been inconsistent:

We agree with Vita-Mix that the district court’s finding that the patentee
disclaimed all stirring appears to be inconsistent with its earlier claim construction. We
further agree with Vita-Mix that the earlier claim construction is correct for all the
reasons articulated by the district court in its claim construction order. To find that the
patentee disclaimed all stirring, regardless of whether and how the stirring acts on air
pockets, ignores the nature of the distinction between a positioning that prevents air
pockets from forming and an operation that breaks up air pockets after they have begun
to form.

The CAFC also found the district court erred on the question of infringement in a summary
judgment context:

We find that the district court erred as a matter of law in disposing of the direct
infringement claims by requiring direct evidence of infringement. The court discounted
the accusations against Mr. Oldroyd and Mr. Daniels because there was no testimony
or footage showing actual infringement in those cases. Such evidence, however, is not
required. Direct infringement can be proven by circumstantial evidence. Moleculon
Research Corp. v. CBS, Inc., 793 F.2d 1261, 1272 (Fed. Cir. 1986). Dr. Swanger’s
testimony, accepted as true for summary judgment purposes, establishes that the
accused blenders will necessarily infringe under certain circumstances.

The CAFC also found the district court erred on evidentiary issues:

Dr. Traylor’s testimony need not establish the
ultimate question of infringement to be relevant. See Daubert v. Merrell Dow Pharms.,
509 U.S. 579, 591 (1993) (holding that evidence is relevant if it may assist the trier of
fact in resolving a factual dispute); Moleculon, 793 F.2d at 1272. Dr. Traylor’s testimony
is relevant to the question of whether users tend to insert the stir stick into the pitcher
without stirring. See Fed. R. Evid. 402 (evidence is relevant if it has any tendency to
make the existence of any fact that is of consequence to the determination of the action
more probable or less probable than it would be without the evidence).

On the topic of contributory infringement:

Contributory infringement imposes liability on one who
embodies in a non-staple device the heart of a patented process and supplies the
device to others to complete the process and appropriate the benefit of the patented
invention. See Ricoh Co. v. Quanta Computer, Inc., 550 F.3d 1325, 1337 (Fed. Cir.
2008).
District courts have found, and we agree, that non-infringing uses are substantial
when they are not unusual, far-fetched, illusory, impractical, occasional, aberrant, or
experimental. Cf. Hilgraeve Corp. v. Symantec Corp., 265 F.3d 1336, 1343 (Fed. Cir.
2001) (finding inducement where the accused device was capable of non-infringing
modes of operation in unusual circumstances); D.O.C.C. Inc. v. Spintech Inc., 36
USPQ2d 1145, 1155 (S.D.N.Y. 1994) (“Contributory infringement liability is not meant
for situations where non-infringing uses are common as opposed to farfetched, illusory,
impractical or merely experimental.”); Haworth Inc. v. Herman Miller Inc., 37 USPQ2d
1080, 1089 (W.D. Mich. 1994) (“The focus is not the utility or ubiquity of the infringing
configuration; the focus is the utility, presence, and efficiency of the non-infringing
configurations.”).

There were trademark issues in this case:

In the Sixth Circuit, a registrant must meet two criteria to succeed in a trademark
infringement case: (1) the plaintiff must possess a protectable mark, Leelanau Wine
Cellars, Ltd. v. Black & Red, Inc., 502 F.3d 504, 512-13 (6th Cir. 2007), and (2) the
plaintiff must show a likelihood of confusion, Tumblebus Inc. v. Cranmer, 399 F.3d 754,
763 (6th Cir. 2005). Where a mark is not registered, a claimant must show that it has
used the mark at issue as a trademark, and that the defendant has used the accused
mark as a trademark. Rock & Roll Hall of Fame & Museum, Inc. v. Gentile Prods., 134
F.3d 749, 753 (6th Cir. 1998).

An unregistered mark is entitled to protection as a trademark if it is inherently
distinctive or has acquired secondary meaning. Homeowners Group, Inc. v. Home
Mktg. Specialists, Inc., 931 F.2d 1100, 1105 (6th Cir. 1991). A mark is inherently
distinctive if its intrinsic nature serves to identify a particular source. Abercrombie &
Fitch Stores, Inc. v. Am. Eagle Outfitters, Inc., 280 F.3d 619, 635 (6th Cir. 2002).

There was bad news for the patentee as to the claim construction analysis by the CAFC:

As a preliminary matter, the court made a point of explaining that it was reviewing
the validity issues under “its own” claim construction and not Vita-Mix’s proffered claim
construction. While it is not entirely clear what claim construction the court refers to as
its own in this explanation, it appears that the court is applying a construction that
excludes all stirring. As explained in Part I.A. above, we find that a construction that
excludes all stirring is inconsistent with the district court’s original claim construction
order. We find that the court’s original claim construction order is correct, and that the
validity issues, remanded for the reason explained below, should be reconsidered under
the proper claim construction.

As to a false statement by the inventor:

Basic’s inequitable conduct charge on appeal is that an inventor of the ’021
patent made a false statement in a declaration when he distinguished low-powered prior
art blenders as incapable of forming air pockets around the blades. In response to a
prior art rejection, inventor John Barnard submitted a declaration to the patent office that
the cited prior art reference was irrelevant because it disclosed a low-powered blender.
Mr. Barnard stated that such blenders did not usually form air pockets around the
blades, and thus do not bear on the claimed solution to the air pocket problem in high-
power blenders. Basic offers an additional prior art reference as evidence that this
statement is false. In his deposition, Mr. Barnard explained that, regardless of whether
the statement is actually false, he believed the statement to be true at the time that he
made it. With no other evidence in the record, the district court correctly found that
Basic made no genuine showing of deceptive intent.