Invalidity dossier
US 7200145
Private VLANs
Current assignee: Cisco Systems Inc
Added 9/23/2026, 8:50:55 PM
Active provider: DeepSeek · deepseek-flash
Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
US7200145B1 — "Private VLANs" — Overview
Title: Private VLANs
Patent number: US7200145B1
Assignee/current assignee (as listed): Cisco Systems Inc; original assignee Cisco Technology Inc
Inventors: Thomas J. Edsall, Marco Foschiano, Michael Fine, Thomas Nosella
Application number: US10/840,212; filed 2004-05-05
Priority date: 2000-05-22 (priority claimed from US09/575,774)
Publication/grant date: 2007-04-03
Purpose (per the excerpt): To separate different users' traffic on a shared switch at Layer 2, because Layer 3 subnet-based separation is limited in the number of subnets available and burdensome to manage at scale. The stated need is "a better way to keep the message traffic of different users separate in a computer network… particularly a method which can scale to a large number of users."
Plain-language scope (per the excerpt): The invention uses a Layer 2 switch (bridge) with Virtual Local Area Networks (VLANs) defined within the switch. Three new port types are defined—promiscuous, isolated, and community—and three internal VLAN types—primary, isolated, and community. Promiscuous ports connect to Layer 3/Layer 4 devices such as routers, load balancers, and administrative workstations. Isolated and community ports connect to individual users' servers and exchange packets with promiscuous ports via the internal VLANs. An isolated port cannot transfer packets to another isolated port; a community port can transfer packets to a designated number of community ports. The primary VLAN connects to all promiscuous, isolated, and community ports, receives packets arriving at promiscuous ports, and transfers them to isolated or community ports; an isolated or community port cannot transfer packets to the primary VLAN, making the primary VLAN a one-way connection. The excerpt is cut off mid-sentence describing the isolated VLAN.
Source: https://patents.google.com/patent/[US7200145](/patent/US7200145)/en
Not established by the excerpt: The full text of the claims; the complete description of isolated and community VLAN operation; any prior-art analysis; litigation, ownership-transfer, or legal-status details (the source notes these are assumptions, and this overview does not assess them).
Generated 10/1/2026, 9:41:06 PM
Cases on file (0)
Specific litigation cases in our database that name US patent 7200145. The free-form analysis below may also discuss cases beyond this list.
No cases on file mention this patent. Upload a CSV or add a case manually in Admin → Manage litigation cases.
Litigation summary
Past and pending lawsuits — plaintiffs, defendants, jurisdictions, outcomes, and notable rulings.
Proceedings on file (0)
All PTAB activity →AIA trial proceedings (IPR / PGR / CBM) filed at the USPTO Patent Trial and Appeal Board against this patent. Sourced from the USPTO Open Data Portal and refreshed every six hours; each proceeding number deep-links to the PTAB E2E docket.
No PTAB proceedings on file. This patent has not been challenged via IPR, PGR, or CBM. The absence is itself a signal — well-asserted patents eventually attract IPRs. The LLM analysis below may surface filings the ODP feed hasn’t indexed yet.
PTAB challenges
AIA trial proceedings at the USPTO Patent Trial and Appeal Board — IPR, PGR, and CBM. Petitioners, judge panels, claim-level invalidation outcomes from Final Written Decisions, and Federal Circuit appeals. The single most important defensive datapoint after litigation history.
Assignment history
Inventors, original assignee, and the chain of ownership recorded with the USPTO — including the correspondent attorney who recorded each assignment, since shell-LLC chains often share one repeat-player attorney even when the entity names look unrelated. Surfaces NPE / patent-troll patterns: shell-entity transfers, known asserters in the chain, repeat correspondent fingerprints, pre-litigation assignments, and bankruptcy fire-sales.
Prior art
Earlier patents, publications, and products that may anticipate or render the claims unpatentable.
Obviousness
Combinations of prior art that suggest the claimed invention would have been obvious under 35 U.S.C. § 103.
Extensions
Patent term adjustments, term extensions, continuations, divisionals, family members, and expiration dates.
Derivative works
Defensive disclosure: derivative variations of each claim designed to render future incremental improvements obvious or non-novel.