Arista Networks, Inc. v. Cisco Systems, Inc.
908 F.3d 792
Fed. Cir.2018Background
- Arista filed an inter partes review (IPR) challenging claims of Cisco’s U.S. Patent No. 7,340,597, which claims a communications device with a logging module that "broadcasts" configuration changes (often by multicast).
- The PTAB instituted review, upheld several claims (29, 63, 64, 73, 86) as patentable, and invalidated others; the Board construed "broadcast" to mean transmission to all destinations on a network.
- Arista (founded by former Cisco employees including the inventor Dr. David Cheriton) appealed the Board’s claim construction for "broadcast." Cisco cross-appealed, arguing assignor estoppel should bar Arista from challenging the patent.
- The specification’s only disclosed example of "broadcast" is multicasting to a multicast address ("one or more security monitors" that must subscribe), which does not require delivery to all network devices.
- The Federal Circuit concluded the Board’s construction excluded the patent’s sole disclosed embodiment and remanded on claim construction; it also held assignor estoppel does not bar IPRs because 35 U.S.C. § 311(a) permits "a person who is not the owner of a patent" to file an IPR.
Issues
| Issue | Arista's Argument | Cisco's Argument | Held |
|---|---|---|---|
| Proper construction of "broadcast" in the ’597 patent | "Broadcast" means a transmission to one or more devices (consistent with the spec’s "one or more security monitors") | "Broadcast" means transmitting to one or more devices but where sender does not specify which devices will receive it (or Board’s narrower meaning: to all network destinations) | Court: "broadcast/broadcasting" = transmission to one or more devices using a multicast address; Board’s "to all destinations" construction reversed and case remanded for reconsideration under correct construction |
| Whether assignor estoppel bars an assignor (or its successor) from filing/obtaining relief in an IPR | Arista: §311(a) allows any person who is not the patent owner to file an IPR; thus assignor estoppel does not apply in IPRs | Cisco: common-law assignor estoppel should bar Arista (inventor assigned to Cisco, then founded Arista); Board erred by refusing estoppel | Court: §311(a) unambiguously permits a person who is not the owner to file an IPR; assignor estoppel has no place in IPR proceedings; Board’s refusal affirmed |
Key Cases Cited
- Cuozzo Speed Techs., Inc. v. Lee, 136 S. Ct. 2131 (2016) (§314(d) "no appeal" provision limits review of certain institution decisions)
- Wi‑Fi One, LLC v. Broadcom Corp., 878 F.3d 1364 (Fed. Cir. 2018) (en banc) (clarifies scope of Cuozzo and what institution-related decisions are reviewable)
- Husky Injection Molding Sys. Ltd. v. Athena Automation Ltd., 838 F.3d 1236 (Fed. Cir. 2016) (panel opinion on assignor estoppel in PTO context)
- Westinghouse Elec. & Mfg. Co. v. Formica Insulation Co., 266 U.S. 342 (1924) (historic statement of assignor estoppel doctrine)
- Mentor Graphics Corp. v. Quickturn Design Sys., Inc., 150 F.3d 1374 (Fed. Cir. 1998) (assignor estoppel prevents assignor from attacking validity)
- Diamond Sci. Co. v. Ambico, Inc., 848 F.2d 1220 (Fed. Cir. 1988) (discussion of assignor estoppel and its post‑Lear uncertainty)
- GE Lighting Sols., LLC v. AgiLight, Inc., 750 F.3d 1304 (Fed. Cir. 2014) (do not construe claims to exclude the preferred or sole disclosed embodiment)
- SAS Inst., Inc. v. Iancu, 138 S. Ct. 1348 (2018) (limitations on PTAB institution and scope of judicial review)
- Lear, Inc. v. Adkins, 395 U.S. 653 (1969) (licenses and invalidity challenges; affected vitality of estoppel doctrines)
- Astoria Fed. Sav. & Loan Ass’n v. Solimino, 501 U.S. 104 (1991) (courts assume Congress legislates against common-law background unless statute indicates otherwise)