B. The Doctrine of “Disavowal,” which Plaintiffs Misapply.

Plaintiffs rely on the doctrine “disavowal” for several of their proposed constructions. The “disavowal” doctrine is a rule of claim construction that is frequently invoked but rarely applicable. First, the doctrine only applies where the disavowal is “clear and unmistakable.” See Cordis Corp. v. Medtronic Ave, Inc., 511 F.3d 1157, 1177 (Fed Cir. 2008) (“alleged disavowing actions or statements made during prosecution [must] be both clear and unmistakable”). Second – and very important here – the alleged disavowal must be made by the patentee, not the examiner. Salazar v. Procter & Gamble Co., 414 F.3d 1342, 1347 (Fed. Cir. 2005) (“[U]nilateral statements by an examiner do not give rise to a clear disavowal of claim scope by an applicant,” as “the applicant has disavowed nothing.”); Univ. of Pittsburgh of Commonwealth System of Higher Educ. v. Hedrick, 573 F.3d 1290, 1296-97 (Fed. Cir. 2009) (“A wide chasm exists between the weak inference from the [interview] summary . . . and a clear and unmistakable disavowal as required to limit a claim term.”)

C. It Is Improper to Import Limitations from the Specification Into the Claims.

While claim limitations must be construed in light of the specification and prosecution history, it is improper to import limitations into the claims where such limitations are not present in the language of the claim itself. Phillips, 415 F.3d at 1323. A difference exists between construing a term appearing in a claim versus adding a limitation that does not appear in the claim in the first instance. The former is permissible, while the latter is not. See, e.g.,

Interactive Gift Express, Inc. v. Compuserve, Inc., 256 F.3d 1323, 1331 (Fed. Cir. 2001) (“in looking to the specification to construe claim terms, care must be taken to avoid reading ‘limitations appearing in the specification . . . into [the] claims’”) (citations omitted); Burke, Inc. v. Bruno Indep. Living Aids, Inc., 183 F.3d 1334, 1340 (Fed. Cir. 1999) (“Consistent with the principle that the patented invention is defined by the claims, we have often held that limitations cannot be read into the claims from the specification or the prosecution history”).

Although the specification may indicate that certain embodiments are preferred, references to preferred embodiments are not claim limitations. Teleflex, Inc. v. Ficosa N. Am. Corp., 299 F.3d 1313, 1327 (Fed. Cir. 2002) (“the number of embodiments disclosed in the specification is not determinative of the meaning of disputed claim terms”).