965 F.3d 1299
Fed. Cir.2020Background
- Packet Intelligence owned U.S. Patents 6,665,725; 6,839,751; and 6,954,789, claiming systems/methods to parse packets and identify "conversational flows" (packets related to the same activity across disjoint connections).
- NetScout's accused products were GeoBlade and G10 (GeoProbe); the district court tried infringement, damages, willfulness, and invalidity; jury found willful infringement, awarded pre‑suit and post‑suit damages, and the court enhanced damages and found claims §101‑eligible.
- Claim 19 of the ’789 patent (representative) recites a packet monitor with parser subsystem, flow‑entry memory, lookup engine, and flow insertion engine; parties disputed whether the claims require correlating separate connection flows into conversational flows.
- NetScout challenged infringement, §101 eligibility, anticipation/inventorship (§102/§102(f)), pre‑suit damages (marking under §287 and use of method claims), and willfulness on appeal to the Federal Circuit.
- The Federal Circuit affirmed infringement, §101 eligibility, anticipation/inventorship findings, and willfulness; but it reversed the pre‑suit damages award (and vacated enhancement) because Packet Intelligence failed to prove that an identified unmarked licensed product (Exar MeterFlow) did not practice the ’789 patent and method‑claim theories could not save the pre‑suit award.
Issues
| Issue | Packet Intelligence's Argument | NetScout's Argument | Held |
|---|---|---|---|
| Infringement (claim 19 representative) | Accused products implement parser, flow entries, lookup and insertion; memory contains info sufficient to associate conversational flows | Claim requires correlating separate connection flows into conversational flows; accused products only track connection flows | Jury verdict affirmed: claims need not require "joining" flows; substantial evidence (Dr. Almeroth) supports infringement finding |
| Patent eligibility (§101) | Claims solve a specific technical problem in networks (identifying disjointed connection flows), are rooted in computer tech and show improved network monitoring | Claims are an abstract idea (collecting/comparing/classifying packet info); reliance on spec improperly supplies implementation | Affirmed: claim 19 not directed to an abstract idea when read in light of the specification; patents are §101‑eligible (majority). Note: Judge Reyna concurred in part and would have reversed on §101 |
| Invalidity / inventorship / anticipation (§102, §102(f)) | Prior RMON Track Sessions probe does not disclose correlating conversational flows; Track Sessions produces a single replaced flow entry and lacks application‑level visibility | Track Sessions (pre‑priority) anticipated/was inventor work product for claimed functionality | Jury verdict rejecting NetScout's §102 and inventorship defenses affirmed; substantial evidence supported district court/jury crediting Packet Intelligence's expert over NetScout's expert |
| Pre‑suit damages (marking §287 and method claims) | Licensed products and NetScout's own pre‑suit internal uses/support/testing justify pre‑suit damages and royalty base | Exar/Huawei/Cisco licensed products (e.g., MeterFlow) were unmarked and may practice the ’789; NetScout identified unmarked products so burden shifted to Packet Intelligence to prove non‑practice; internal use alone insufficient to support method‑claim damages | Reversed: Packet Intelligence failed to prove MeterFlow did not practice the ’789 claim so cannot recover pre‑suit damages for that patent; method‑claim theories did not supply adequate pre‑suit damages evidence. Enhancement tied to pre‑suit award vacated |
| Willfulness | Evidence (executive statements, continued sales) supports willful infringement | Lack of patent review by executives and phase‑out of products show no willfulness | Jury willfulness verdict affirmed: substantial evidence supports willfulness finding |
Key Cases Cited
- Alice Corp. v. CLS Bank Int’l, 573 U.S. 208 (2014) (two‑step patent‑eligibility framework)
- Mayo Collaborative Servs. v. Prometheus Labs., 566 U.S. 66 (2012) (framework for inventive concept inquiry)
- Enfish, LLC v. Microsoft Corp., 822 F.3d 1327 (Fed. Cir. 2016) (software claim held not abstract where it improved computer functionality)
- SRI Int’l, Inc. v. Cisco Sys., Inc., 930 F.3d 1295 (Fed. Cir. 2019) (network‑monitoring claims rooted in computer technology held eligible)
- Berkheimer v. HP Inc., 881 F.3d 1360 (Fed. Cir. 2018) (factual issue whether claim elements are conventional/routine may preclude summary §101 rulings)
- Arctic Cat Inc. v. Bombardier Recreational Prods. Inc., 876 F.3d 1350 (Fed. Cir. 2017) (burden‑allocation on marking: accused infringer must identify unmarked products to shift burden)
- Two‑Way Media Ltd. v. Comcast Cable Commc’ns, 874 F.3d 1329 (Fed. Cir. 2017) (claims held abstract when they recite functional results without sufficient implementation detail)
- Data Engine Techs. LLC v. Google LLC, 906 F.3d 999 (Fed. Cir. 2018) (claims must be read in light of the specification in §101 analysis)
- Joy Techs., Inc. v. Flakt, Inc., 6 F.3d 770 (Fed. Cir. 1993) (method claims require proof of actual use for direct infringement)
- Teva Pharm. USA, Inc. v. Sandoz, Inc., 574 U.S. 318 (2015) (claim construction may involve subsidiary factual findings)