On February 10, 2021, the Federal Circuit issued a precedential decision affirming the district court's decision finding the claims of U.S. Patent Nos. 6,894,811, 7,489,423, 8,040,574, and 8,294,915 invalid as indefinite.  (Slip opinion here)

Judge Leonard Stark previously found the terms “passive link” and “computer” indefinite due to inconsistent positions the applicant took during the prosecution and reexamination of the subject claims.  Infinity Comput. Prods., Inc. v. Oki Data Ams., Inc., No. 18-463, 2019 WL 2422597, at *4 (D. Del. June 10, 2019), reconsideration denied, 2019 WL 5213250 (D. Del. Oct. 16, 2019).

The asserted patents share a common specification and are directed to using a fax machine as a printer or scanner for a personal computer.  During prosecution, the applicant amended the claims to include a “passive link” between the fax machine and the computer.  The coined term “passive link” was not defined (or even recited) in the specification.  In order to overcome a prior art rejection, the applicant argued that the claimed “passive link” did not allow for intervening circuitry (e.g., a fax modem), between the fax machine and the computer.  The applicant argued that circuitry, even when contained within the box containing the computer, “should be regarded as a peripheral device to the computer which processes data before it is transmitted to the I/O bus of the computer.”  The Court concluded “this position would lead one of ordinary skill to believe a passive link does not end at the computer's port but rather reaches to the I/O bus of the computer—especially ‘[g]iven the role of the statement in gaining allowance of the claims'”, quoting Teva, 789 F.3d 1335, 1344 (Fed. Cir. 2015).  Slip Op. at 13.

However, during reexamination, the patent owner argued that the “passive link” included the embodiments of Figures 2b–d – embodiments that include intervening circuitry between the fax machine and the computer's I/O bus within the box containing the computer.  The Court concluded “this argument would lead one of ordinary skill to believe a ‘passive link' ends at the computer's port.”  Id.

In reaching its decision the Court confirmed its prior holding in Teva that “[t]he public-notice function of a patent and its prosecution history requires that we hold patentees to what they declare during prosecution.”  Id.  The Court concluded, “the intrinsic evidence leaves an ordinarily skilled artisan without reasonable certainty as to where the passive link ends and where the computer begins.” Id.

Additionally, the Court rejected the patent owner's argument that the district court had misinterpreted statements made during prosecution on the ground that “‘we hold patentees to the actual arguments made, not the arguments that could have been made' during prosecution”, and expressly acknowledged the Supreme Court's warning in Nautilus “against ‘viewing matters post hoc' to ‘ascribe some meaning to a patent's claims.'” Slip Op. at 14.

The Court also rejected the need for expert testimony where the “contradictory positions are plain from the patent record”.  Slip Op. at 15.

Lastly, the Court expressly recognized that, “in a vacuum, it might seem odd to hold ‘computer' indefinite” especially when the specification identifies examples of commercial computers, such as an “Apple Macintosh” and an “IBM PC.” Id. at 17.  The Court explained that the “indefiniteness here does not reside in the term ‘passive link' or ‘computer' on its own but rather in the relationship between the two in the context of these claims.”   Thus, it is the unique facts of this case that deprive the public of any reasonable certainty as to where the “passive link” ends and where the “computer” begins, thereby rendering the claimed term “computer” indefinite. 

Marc Robert Labgold of Marc R. Labgold, P.C., Reston, VA, argued for defendant-appellee. Also represented by Patrick J. Hoeffner; Jeffrey T. Castellano, Andrew E. Russell, John W. Shaw, Shaw Keller LLP, Wilmington, DE.