Invalidity dossier
US 5127042
Cellular cordless telephone
Current assignee: Motorola Solutions Inc
Added 9/23/2026, 6:18:01 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 5,127,042 A
Title: Cellular cordless telephone
Patent number / application: US 5,127,042 A; application US 07/660,180, filed 1991-02-25; granted and published 1992-06-30. Priority date 1988-09-23, claimed from US 07/249,041 (patent US 4,989,230 A). Status listed as "Expired – Lifetime," with anticipated expiration 2009-06-30.
Inventors / assignee: Steven F. Gillig and Glen E. Pederson; original assignee Motorola Inc. The source also lists current assignee Motorola Solutions Inc, noting listed assignees may be inaccurate and that Google has not performed a legal analysis.
Purpose: The patent relates generally to cellular telephones, and more particularly to an improved cellular cordless telephone providing both cellular and cordless telephone service. A stated motivation is cost: a cellular call is described as costing as much as seven times a cordless (landline-based) call. Cordless telephones are limited in range and unsuitable for vehicles, whereas cellular service covers a large metropolitan area.
Plain-language scope (as described in the excerpt): A cellular cordless telephone (CCT) contains both a cordless telephone transceiver and a cellular telephone transceiver plus a microcomputer, keypad, display, audio switch, and handset. The CCT may simultaneously operate as a cellular telephone and a cordless telephone. Figures 4–8 describe processes for placing/receiving cellular and cordless calls, originating and receiving calls per user-selectable preference, simultaneously processing both a cellular and a cordless call with three-way linking, and automatically transferring between a cellular call and a cordless call. Embodiments include a single-antenna unit (CCT 100) or separate antennas (CCT 200), and a plug-in cordless accessory housing coupling to a cellular telephone. Cordless channels are described as 46–49 MHz and cellular channels as 824–894 MHz.
What the excerpt does not establish: It does not provide the actual wording of the claims, the complete specification, or the full flow-chart details. It does not establish litigation, ownership transfers, validity, or prior-art conclusions; assignee and legal-status entries are explicitly flagged as assumptions. Several referenced patents/manuals are cited but not reproduced.
Generated 10/1/2026, 9:42:53 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)
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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
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.