Advanced Fiber Technologies Trust v. J&L Fiber Services, Inc.

On April 3, 2012, the Federal Circuit ruled (2 to 1, opinion by Judge Lourie) that a district court (N.Y., N.D.) incorrectly granted summary judgment of noninfringement in favor of J&L Fiber Services, Inc. (“J&L”).  Advanced Fiber Technologies (“AFT”), owner of U.S. Pat. No. 5,200,072 and RE 39,940, sued J&L after it began selling its V-Max wedgewire screens for use in paper and pulp processing.

At issue was whether the district court erred in concluding that AFT’s claims excluded, as a matter of law, screens having the wedgewire construction sold by J&L.  The outcome of the case turned on claim interpretation, in this case, the meaning of “perforated.”  Interestingly, “perforated” appears not in AFT’s claims but in a definition of “screening medium” adopted by the district court with help from the Handbook of Paper & Pulp Technology.  AFT relied upon this reference during prosecution in distinguishing its invention from U.S. Pat. No. 4,276,265 (“Gillespie”), which AFT argued did not relate to paper and pulp technology.

Based on Handbook definitions, the district court interpreted “screening medium” as a “perforated barrier through which stock is passed to remove oversized, troublesome, and unwanted particles from good fiber.”  Although the definition was otherwise acceptable, the parties disagreed about how the court should interpret “perforated.”  According to AFT, a “perforated” barrier is one “having holes or openings” (i.e., consistent with wedgewire construction as well as a pierced plate), while J&L argued that one of ordinary skill would understand “perforated” to mean “pierced or punctured with holes” (thereby excluding wedgewire).  After studying the specification and prosecution history, the district court chose the latter definition, so J&L prevailed.

The Federal Circuit reversed, ruling that the district court “erroneously construed ‘perforated’ using extrinsic evidence that contradicts the intrinsic evidence of record.”  According to the majority, the district court’s analysis “went awry” in its interpretation of “perforated.”  The claims “do not require the screening medium to be made by puncturing or piercing, they simply limit the screening medium to “having a plurality of openings therethrough.”  The Federal Circuit said the district court also erred by disregarding AFT’s one-sentence disclosure that “[a]lso, a wedgewire screening plate may be used.”  After concluding that J&L’s wedgewire construction is consistent with claim language that reads “having a plurality of openings,” the Federal Circuit reversed the summary judgment of noninfringement and remanded for further proceedings.

Although the opinion is silent on this point, perhaps the Federal Circuit felt that the equities tilted in AFT’s favor.  Did the district court’s holding that J&L’s device was noninfringing as a matter of law deprive AFT of a fair chance to prove the merits of its case?  Moreover, is that concern amplified by an outcome that turned not on a court’s construction of actual claim language but on derivative construction?  In other words, could something have been lost in translation in this game of Whisper Down the Lane?

Judge Dyk’s dissenting opinion is worth reading.  He would have upheld the district court’s holding of noninfringement.  He wrote that “the intrinsic record demonstrates that ‘perforated’ in this context requires that holes or openings be made through an otherwise solid object, such as a plate.  Because the accused product’s wedgewire construction does not meet this limitation . . . the district court’s grant of summary judgment of noninfringement should be affirmed.”  In Judge Dyk’s view, prosecution history estops AFT from arguing that its claims encompassed the wedgewire construction.  During prosecution, AFT had argued that its invention was not anticipated by Gillespie, a reference that taught the use of a similar wedgewire screen.  “By explicitly adopting a definition of the term ‘screening medium’ or ‘screening plate,’ AFT excluded wedgewire construction from the scope of the claims.”  Judge Dyk was less impressed than the majority that AFT had managed to disclose a wedgewire embodiment: “Not every embodiment disclosed in the specification necessarily falls within the scope of the claims.”

Judge Dyk’s concerns are well-founded.  The patent examiner considered Gillespie to be novelty-destroying.  To satisfy the examiner, AFT had to argue that its screen differed in important respects from Gillespie’s device.  If not different because of the perforated plate as opposed to wedgewire construction, then how?  The case for prosecution history estoppel seems clear enough.

Holy rat traps, Batman, claim construction is messy!  Language is riddled with holes, apertures, piercings, perforations, and punctures.  Unfortunately, this won’t be the last case in which the outcome will depend on interpretation of language that neither the inventors nor their attorney chose.


~ Jon Schuchardt


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