A borrowed term of analogy rather than a true term of art is not sufficient to establish a plain and ordinary meaning to one skilled in the particular field to which the application pertains. Here, for example, a “seal” described parenthetically for use in the field of cryptography was found to be at best a term adapted from a distinct (if not entirely unrelated) field (e.g., contract law), and therefore particular to the invention and unique in the cryptographic arts. It may therefore be best to avoid overly characterizing any adapted terminology beyond its analogous value unless a more specific lexicographic definition is desired.
Background / Facts: The patents being asserted here are directed to encrypting electronic documents so that they may be openly distributed over insecure networks, such as the Internet, but at the same time may be accessible by permitted recipients. This encryption system provides security by transmitting a data structure called a “seal” along with the encrypted document. The “seal,” in turn, contains an encryption key or information to generate an encryption key, which allows recipients to unlock the encrypted documents.
Issue(s): Whether the ordinary and customary meaning of “seal” according to a general-purpose dictionary is controlling in this instance.
Holding(s): No. “In the two patents at issue, the term ‘seal’ is used in a manner particular to the invention and unique to the cryptographic arts.” In characterizing the specification’s use of a “seal” as a borrowed term of analogy rather than a true term of art, the court noted that “[i]ntentionally off-setting the term ‘seal’ and providing additional, term-specific explanations are signals that ‘seal’ is used in a context-specific manner, thereby undercutting [the patentee’s] argument for a general-use dictionary definition. … We find no error in the district court’s refusal to apply a dictionary definition of ‘seal’ in view of the specification and the field of invention.” Accordingly, the court affirmed a claim construction based on the specification’s more narrow description of the general “invention” in the Summary section and elsewhere.