A Disavowal, If Clear and Unambiguous, Can Lie in a Single Distinction Among Many

Computer Docking Station Corp. v. Dell, Inc., [2007-1169, -1316] (March 21, 2008) [RADER, Michel, Plager] The Federal Circuit affirmed summary judgment that defendants did not did not infringe claims 17-20, 22, 24, and 26-28 of Computer Docking Station’s U.S. Patent No. 5,187,645 because the patentee disavowed an interpretation of "portable computer" that would encompass computers with a built-in displays or keyboards. The Federal Circuit also affirmed the denial of attorneys fees to defendants, finding that the case was not exceptional.
SIGNIFICANCE: An applicant can make a disavowal of claim scope even if it is just one of several distinctions that the applicant drew.
BRIEF: The ’645 patent claims a portable microprocessor system with sufficient processing power, memory, and network compatibility for business applications. The computer can be connected to peripherals either individually or through a docking connection. The specification explains that a keyboard and visual display are "options available with the system." At issues was the claim requirement that of a single connector "for making all connections from the microprocessor to said specific computer peripheral devices". In distinguishing over the prior art, which disclosed a laptop computer and a docking module that facilitates operation on a desktop, the Computer Docking Station expressly defined their invention in different terms, and amended the claims.
The district court construed "portable computer" and "portable computer microprocessing system" in the preambles of the asserted claims to mean "a computer without a built-in display or keyboard that is capable of being moved or carried about." The district court determined that the prosecution history and the specification distinguished the claimed invention from a laptop computer, and further that applicant's arguments to distinguish over the prior art amounted to a clear and unmistakable disavowal of computers with built-in displays or keyboards. Thus the district court construed the phrase "said single connector for making all connections from the microprocessor to said computer peripheral devices" to require "that all individual peripheral device connections on the housing that connect to the microprocessor also pass through the single connector." Based on these claim interpretations, CDSC sought entry of final judgment of non-infringement, and appealed.
The Federal Circuit gave a cogent review of the canons of claim construction:

The words of the claims define the scope of the patented invention. . .
. "It is well-settled that, in interpreting an asserted claim, the court
should look first to the intrinsic evidence of record, i.e., the patent itself,
including the claims, the specification and, if in evidence, the prosecution
history." . . . Claim terms are generally given their ordinary and
customary meaning, which is "the meaning that the term would have to a person of
ordinary skill in the art in question at the time of the invention." . . .
However, the person of ordinary skill is deemed to read the claim terms in the
context of the entire patent, including the specification and prosecution
history. . . . Occasionally specification explanations may lead one of
ordinary skill to interpret a claim term more narrowly than its plain meaning
suggests. Nonetheless, this court will not countenance the importation of claim
limitations from a few specification statements or figures into the claims . . .
particularly if those specification extracts describe only embodiments of a
broader claimed invention . . . By the same token, "the specification ‘is
always highly relevant to the claim construction analysis. Usually, it is
dispositive; it is the single best guide to the meaning of a disputed term.’" .
. . The specification may show that "the patentee has disclaimed subject
matter or has otherwise limited the scope of the claims."

The Federal Circuit added that that statements made during prosecution may also affect the scope of the claims. The Court said a patentee could do so, for example, by clearly characterizing the invention in a way to try to overcome rejections based on prior art. The Federal Circuit said that doctrine of prosecution disclaimer "protects the public’s reliance on definitive statements made during prosecution" by "precluding patentees from recapturing through claim interpretation specific meanings [clearly and unmistakably] disclaimed during prosecution," observing that "[c]laims should not be construed 'one way in order to obtain their allowance and in a different way against accused infringers.'"
The Federal Circuit said that prosecution disclaimer does not apply to an ambiguous disavowal. The Federal Circuit gave several examples where prosecution disclaimer does not apply, including where the applicant simply describes features of the prior art and does not distinguish the claimed invention based on those features, or where the specification expressly defines a claim term and "remarks made to distinguish claims from the prior art are broader than necessary to distinguish the prior art, the full breadth of the remark is not ‘a clear and unambiguous disavowal of claim scope as required to depart from the meaning of the term provided in the written description.’"
The Federal Circuit found that "portable computer" and "portable computer microprocessing system" as used in the preambles of the asserted claims limited their scope because the clearly recite a necessary and defining aspect of the invention, specifically its portability. The written description and applicants’ statements during prosecution emphasized this feature of the invention. The Federal Circuit then determined that the applicant's owns statements precluded presence of a key board or display, noting that in overcoming a rejection based on a lap top computer, applicant argued that its system provided all of the interfaces for these devices at a set of interface connectors on the rear bezel of the housing. The applicants also contrasted the advantages of their invention:

Rather than requiring a portable display and keyboard, the present invention
concentrates on portability of an exceptionally large memory capacity in hard
disk drive. . . . For the same sized unit as a conventional lap-top computer,
the invention does require that peripherals be made available at each location,
a requirement that would lead one away from the present invention. However, even
that requirement can be an advantage over laptop computers in that than
requiring a portable display and keyboard, the present invention concentrates on
portability of an exceptionally large memory capacity in hard disk drive. . . .
For the same sized unit as a conventional lap-top computer, the invention does
require that peripherals be made available at each location higher quality
peripherals will more likely be used since they need not be transported. Thus,
lap-top machines make concessions in memory, display and other areas in favor of
portability. The Applicants’ system, on the other hand, is a portable full
service microprocessing system which concedes portability of peripherals.

In these arguments the Federal Circuit agreed that applicant had disavowed a keyboard or screen. The Federal Circuit observed that the applicants distinguished their invention from the prior art in multiple ways. Nonetheless a disavowal, if clear and unambiguous, can lie in a single distinction among many. The Federal Circuit said that Examiner's statement of a different reason for allowance did not erase the applicants’ clear disavowal of laptops, noting that it has found prosecution statements relevant to claim construction even though the examiner did not rely on them.
LOF: The Federal Circuit reviews an exceptional case determination under § 285 for clear error.
LOF: The Federal Circuit reviews a denial of attorney fees under 35 U.S.C. § 285 for an abuse of discretion. The Federal Circuit found no error in finding the case was not exceptional, in part because the disavowal was not so apparent at the start of the claim construction process, and affirmed the denial of attorneys fees.