Invalidity dossier
US 7249280
Cheap paxos
Current assignee: Microsoft Technology Licensing LLC
Added 9/23/2026, 6:47:07 PM
Active provider: DeepSeek · deepseek-flash
Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
Patent Overview: US 7,249,280 B2 — "Cheap Paxos"
Title: Cheap paxos
Patent number: US 7,249,280 B2
Application number: US 10/872,338
Inventors: Leslie B. Lamport; Michael T. Massa
Original assignee: [Microsoft Corp.](/litigations/by-plaintiff/Microsoft%20Corp.)
Current assignee (per source): Microsoft Technology Licensing LLC
Priority/filing date: 2004-06-18
Publication date (grant): 2007-07-24
Earlier publication: US 2005/0283659 A1 (2005-12-22)
Legal status (per source): Expired – Fee Related; adjusted expiration listed as 2026-01-24
Source: https://patents.google.com/patent/US7249280/en
Purpose and plain-language scope
The supplied text identifies the invention only by its title and its recurring prior-art keywords: "quorum," "computing device," "quorums," and "computing devices." On that basis, the patent concerns distributed computing and quorum-based coordination among computing devices—the domain of the Paxos family of consensus algorithms, to which the title "Cheap paxos" alludes. However, the excerpt provided does not include the abstract, specification, or claims, so the actual technical scope of the invention cannot be described from this source alone.
The bibliographic record does establish: a single inventor pair, a Microsoft-origin assignment, a 2004 filing date, a 2007 grant, a 2014 reassignment to Microsoft Technology Licensing LLC, and a currently expired status with a listed adjusted expiration of 2026-01-24.
What the excerpt does not establish
- The claims' actual language, scope, or breadth.
- The abstract, specification, figures, or detailed description.
- Any specific mechanism by which quorums are selected, reduced, or used.
- Whether the invention relates to reducing quorum size or message cost specifically.
- The number of claims or their dependencies.
- Any prior-art references cited during prosecution.
- Any litigation, validity, or enforceability conclusion.
Note: Per the source's own disclaimer, the listed legal status and assignees are assumptions and not legal conclusions; no independent verification was performed, and none was attempted here.
Generated 10/1/2026, 9:42:35 PM
Cases on file (0)
Specific litigation cases in our database that name US patent 7249280. 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.