Cisco Systems, Inc. v. Cirrex Systems, LLC
856 F.3d 997
| Fed. Cir. | 2017Background
- This case concerns inter partes reexamination of U.S. Patent No. 6,415,082 (the ’082 patent) owned by Cirrex and challenged by Cisco; Cirrex added claims 35–124 during reexamination.
- The PTO Examiner found claims 56, 57, 76, 102, and 103 patentable (equalization and discrete-attenuation claims) but rejected numerous other claims, including those reciting a diverting element inside the PLC. The PTAB affirmed the Examiner on the rejections and found patentability for the five added claims above.
- The disputed technology: a planar lightguide circuit (PLC) that demultiplexes wavelengths, external optical waveguides/elements (diverting elements, amplifiers/attenuators) that act on individual channels outside the PLC, and embodiments showing amplification/attenuation outside the PLC (e.g., Fig. 13) and diverting elements outside the PLC (e.g., Figs. 10–12).
- Key claim language asserted that equalization or discrete attenuation occurs in the PLC (claims 56, 57, 76, 102, 103) or that a diverting element is disposed inside the PLC (representative claim 46). Parties had agreed before the PTAB that equalization/discrete attenuation must occur while light is inside the PLC.
- The core dispute is written-description sufficiency: whether the original specification reasonably conveys possession of embodiments that (a) equalize intensities of different wavelengths while those wavelengths are inside the PLC, (b) discretely attenuate individual channels inside the PLC, or (c) place a diverting element inside the PLC.
Issues
| Issue | Plaintiff's Argument (Cisco) | Defendant's Argument (Cirrex) | Held |
|---|---|---|---|
| Whether claims requiring "equalization" inside the PLC are supported by the original spec | Cisco: specification lacks disclosure of how to equalize different wavelengths while they are inside the PLC; claims thus lack written description | Cirrex: spec supports an embodiment where attenuation inside the PLC equalizes the PLC wavelengths to an outside-added wavelength (creative construction) | Court: Reversed PTAB — written description lacking; equalization must occur among wavelengths while inside the PLC and spec does not disclose how to do that |
| Whether claims reciting "discrete attenuation" inside the PLC are supported | Cisco: attenuation material inside PLC would act collectively, not discretely; spec does not show discrete per-channel attenuation inside PLC | Cirrex: placing attenuation in PLC plus later adding an unattenuated outside wavelength yields effective discrete attenuation | Court: Reversed PTAB — discrete attenuation does not include collectively attenuating all PLC wavelengths; spec does not disclose discrete per-channel attenuation inside PLC |
| Whether claims placing a diverting element inside the PLC are supported | Cisco: figures and description show diverting element located outside the PLC; no disclosure of a diverting element inside the zig‑zag PLC path | Cirrex: Fig. 11 and photolithographic discussion imply a diverting element could be inside the PLC | Court: Affirmed PTAB — substantial evidence supports lack of written description for diverting-element-inside-PLC claims; figures show the element outside the PLC and do not disclose placement or operation inside the PLC |
| Claim construction: whether Board improperly broadened the meaning of equalization/discrete attenuation | Cisco: Board improperly allowed equalization to be to wavelengths outside the PLC and allowed discrete attenuation via later-added outside wavelengths | Cirrex: broader reading is permissible | Court: Corrected Board — equalization/discrete attenuation must occur among wavelengths while they are traveling inside the PLC; Board’s broader construction was incorrect |
Key Cases Cited
- Cuozzo Speed Techs., LLC v. Lee, 136 S. Ct. 2131 (Supreme Court 2016) (claim construction—PTAB applies broadest reasonable interpretation)
- SightSound Techs., LLC v. Apple Inc., 809 F.3d 1307 (Fed. Cir. 2015) (review standards for claim construction)
- AbbVie Deutschland GmbH & Co. v. Janssen Biotech, Inc., 759 F.3d 1285 (Fed. Cir. 2014) (written-description is a question of fact)
- Blue Calypso, LLC v. Groupon, Inc., 815 F.3d 1331 (Fed. Cir. 2016) (substantial-evidence standard for PTAB factual findings)
- Gentry Gallery, Inc. v. Berkline Corp., 134 F.3d 1473 (Fed. Cir. 1998) (original disclosure limits permissible breadth of later claims)
- Carnegie Mellon Univ. v. Hoffmann-La Roche Inc., 541 F.3d 1115 (Fed. Cir. 2008) (broader-claim invalid when specification shows narrower invention)
- PIN/NIP, Inc. v. Platte Chemical Co., 304 F.3d 1235 (Fed. Cir. 2002) (added claims require support in the originally filed application)
- Ariad Pharm., Inc. v. Eli Lilly & Co., 598 F.3d 1336 (Fed. Cir. 2010) (en banc) (written-description test: disclosure must reasonably convey possession of claimed invention)
- Vas-Cath Inc. v. Mahurkar, 935 F.2d 1555 (Fed. Cir. 1991) (quoted standard for written description)
- Cooper Cameron Corp. v. Kvaerner Oilfield Prods., Inc., 291 F.3d 1317 (Fed. Cir. 2002) (discussion of specification limiting claim scope)