Fractured Claim Construction

Agilent Tech., Inc. v. Affymetrix, Inc. (Fed. Cir. 2009)

Agilent’s microarray hybridization genetic analysis patent issued in 2003. After seeing those issued claims, Affymetrix amended a pending application by adding identical claims in order to provoke an interference. The Agilent patent has a priority date of 1998 while the Affymetrix application claims priority back to 1995. The Board of Patent Appeals and Interferences (BPAI) awarded priority to Affymetrix in 2006. That holding was upheld by a N.D. California district court in 2008.

Here, the Federal Circuit reverses – holding that Affymetrix cannot claim priority back to its 1995 filing because that original application “does not satisfy the written description requirement for the claims at issue.” Written description is particularly relevant in interference cases where one party typically copies claims from another patent document.

Claim Construction in an Interference: Several articles have been written on the complicated and ever-changing scope of a patent claim. At the PTO, claims are usually given their broadest reasonable meaning while in litigation, courts look for how a PHOSITA would interpret the scope, etc.. Phillips teaches that proper claim construction looks at the literal language of the claims as well as supporting information from the specification and prosecution history. In an interference, however, the copied claims originally came from another application.

Faced with a split of precedent, the Federal Circuit here decided to continue with multiple interpretations of an individual claim. Following Spina, the court holds that – for the purposes of the written description requirement – the newly added claims should be interpreted based on the specification and history of the opposing source application. However, following Rowe, the Federal Circuit held that for the purposes of novelty and nonobviousness, the newly added claims should be construed based on the specification and history of the amended application.

To be clear, as this court explained in Rowe, when a party challenges written description support for an interference count or the copied claim in an interference, the originating disclosure provides the meaning of the pertinent claim language. When a party challenges a claim’s validity under § 102 or § 103, however, this court and the Board must interpret the claim in light of the specification in which it appears.

This change in primary interpretative materials allowed the Federal Circuit to also change the claim construction and consequently hold that Affymetrix’s application “does not satisfy the written description requirement for the claims at issue.”


  • As a pending application, Affymetrix’s claims had no presumption of validity. “Thus, Agilent’s burden of proving a lack of written description in Affymetrix’s Besemer application is a simple preponderance of the evidence. Eli Lilly & Co. v. Aradigm Corp., 376 F.3d 1352, 1365 (Fed. Cir. 2004).”   

One thought on “Fractured Claim Construction

  1. 1

    a good call–that will somehow put a stop to inventors from amending their pending applications and trying to cover whatever they want to cover. To cover an existing product in the market, the applicant (inventor) may try to amend the claim wordings to achieve the goal. However, if that is not what the inventor is thinking, this decision so made may put the inventor to think twice.

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