Invalidity dossier
US 7555516
Fast Paxos recovery
Current assignee: Microsoft Technology Licensing LLC
Added 9/23/2026, 7:57:41 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: US7555516B2 — "Fast Paxos recovery"
Title: Fast Paxos recovery
Patent number: US7555516B2
Application number: US10/996,350
Inventor: Leslie B. Lamport
Original assignee: Microsoft Corp; current assignee listed as Microsoft Technology Licensing LLC
Prior art date / filing date: 2004-11-23
Publication of application: 2006-07-27 (US20060168011A1)
Grant/publication date: 2009-06-30
Legal status: Active, with an adjusted expiration listed as 2027-07-18
Purpose and plain-language scope (per supplied text):
The patent relates to recovery in a distributed computing protocol known as Paxos — specifically "Fast Paxos recovery." The excerpt's prior-art keywords point to the subject matter: devices, vote, function, leader, messages. In plain terms, the invention concerns how a distributed system of computing devices recovers after a disruption, involving a leader, voting among devices, message exchanges, and a function governing that process. The title indicates the improvement is directed to making Paxos recovery "fast."
Caveats — what the excerpt does not establish:
The supplied text is the Google Patents bibliographic/landing page and is explicitly marked "[Excerpt only; consult the source for omitted text.]" It contains no claims, no detailed description, no drawings text, and no listed prior-art references. Therefore this overview cannot state:
- the actual claimed invention or claim scope;
- the specific technical mechanism by which recovery is made fast;
- the field's problem statement or embodiment details;
- any prior-art U.S. patents or publications relied upon;
- the meaning of "devices," "vote," "function," "leader," and "messages" in the claimed context.
Dates (priority, filing, publication, expiration) are presented by the source as assumptions, not legal conclusions. The listed legal status and assignees are likewise noted by the source as potentially inaccurate and not representative of a legal analysis.
Source: https://patents.google.com/patent/[US7555516](/patent/US7555516)/en
Generated 10/1/2026, 9:41:42 PM
Cases on file (0)
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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.