Invalidity dossier
US 5999598
Added 9/23/2026, 5:01:49 PM
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Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
Patent Overview — US 5999598 A
Title (as listed): "Method and system for used selectable quality of service of facsimile of voice transmissions" (sic — reproduced literally from the source).
Patent number: US5999598A. Application number: US08/909,280. Filing date / priority date: 1997-08-11. Publication (grant) date: 1999-12-07. Inventors: Robert F. Henrick and Ajay K. Jain. Original assignee / current assignee (as listed): AT&T Inc. (originally recorded as AT&T Corporation). Legal status listed: Expired – Lifetime; anticipated expiration 2017-08-11.
Purpose: The invention addresses the problem that facsimile transmission over low-latency networks such as the Internet can fail to meet facsimile protocol timing during congestion, that Internet solutions may fall back to store-and-forward, and that transmitting during peak hours costs far more than off-peak. Its stated object is to let a user select the quality of service and related cost of a facsimile or voice transmission at the time of transmittal.
Plain-language scope: A modified destination number ("MDN") incorporates both the destination telephone number and a quality-of-service indicator. The MDN is dialed manually or automatically by a "double dialer," transmitted via DTMF to a network point of presence (POP), which decodes it and routes the transmission over the appropriate one of several telecommunications networks (e.g., PSTN, LEC, packet-switched/Internet, or a combination) at the corresponding priority. Quality-of-service levels named include "highest," "high," "standard," and "store and forward," selectable via function keys with indicator LEDs. The POP may demodulate/remodulate and packetize facsimile traffic, handle billing, call control and addressing, hold store-and-forward traffic until a predetermined time, and optionally provide voice prompts with voice recognition when no double dialer is present.
Source: https://patents.google.com/patent/US5999598/en
Not established by this excerpt: the full text of any claim, the complete figure descriptions, the detailed description of the flow-chart steps after the point where text is omitted, and the specific commercial products or vendors' equipment beyond those named (Arel Communications, Netcentric, NetExchange). No litigation, ownership-transfer, validity, or prior-art analysis is presented or implied here.
Generated 10/1/2026, 9:43:56 PM
Cases on file (0)
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Litigation summary
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Proceedings on file (0)
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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
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Obviousness
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Extensions
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Derivative works
Defensive disclosure: derivative variations of each claim designed to render future incremental improvements obvious or non-novel.