Emphasizing the public-notice function of a patent’s specification, the US Court of Appeals for the Federal Circuit affirmed a district court’s construction of four patent claim terms based entirely on intrinsic evidence. Indacon, Inc. v. Facebook, Inc., Case No. 15-1129 (Fed. Cir., June 6, 2016) (Stoll, J).

The patent at issue is directed to a system and method for searching, indexing, perusing and manipulating files in a database, particularly through the insertion of automatically generated hyperlinks. Generally, the claimed system (1) allows for creating “custom links” between terms found within a file that are part of a database, (2) provides for a “link term” that forms an association of one or more files within the custom database, and (3) provides for an “alias term” that can be further associated with the “link term.” Indacon disputed the district court’s construction of four claim terms: “alias,” “custom link,” “custom linking relationship” and “link term.”

The district court construed the claim term “alias” as a “textual expression that the user can define to serve as an alternative name or label.” Indacon argued that the term encompasses a textual or graphical hyperlink, not just textual expression. Several of the claims require a link to be established between an “alias” or “alias term” and a plurality of files. The plaintiff agreed that the terms “alias” and “alias term” were used synonymously. However, the Federal Circuit found that the specification explicitly defined the word “term” as “words, numbers, spaces, etc.”

Finding that the specification described an “alias” as a “term,” the Federal Circuit reasoned that the synonym “alias” also must be of the same form as a “term” and similarly limited to textual expression. The Court rejected the notion that the word “etc.” in the specification’s definition of “term” could be stretched to encompass a graphic expression, particularly where all examples of an alias in the specification consist of textual expression, and nothing in the prosecution history was to the contrary. The Court further noted that an “alias” is not a hyperlink. Citing the specification, the Court noted that while a “link” may be established to connect an “alias” or other “link term” to files in the database, the alias itself is not the link.

For the terms “custom link,” “custom linking relationship” and “link term,” the patent owner objected to the district court’s constructions to the extent they excluded creation of a link for less than all instances of a defined term. The Federal Circuit found that the terms have no plain or established meaning to one of ordinary skill in the art. As a result, the terms cannot be construed more broadly than the disclosure in the specification. According to the Court, the specification repeatedly demonstrates that all link terms are capable of being identified and displayed as a link, and that the patent owner’s arguments made during prosecution history supported the district court’s construction. Finding that the public had a right to rely on those prosecution statements, the Court rejected the patent owner’s contention on appeal that the patent applicant’s arguments, made during prosecution, were advanced for reasons unrelated to the language underlying the disputed construction.

Finally, the Federal Circuit rejected the patent owner’s argument that claim differentiation commanded the construction it urged. Noting that the claims cited as a basis for the patent owner’s argument were all independent claims, the Court declined to apply the doctrine of claim differentiation. The Court also found that the claims were not otherwise identical in scope—a prerequisite for applying the doctrine of claim differentiation.