Invalidity dossier
US 6155487
Re-writable display device and system
Current assignee: Individual
Added 9/23/2026, 10:42:11 AM
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 6,155,487 B1
Title: Re-writable display device and system
Patent number / application: US 6,155,487 A (application US09/443,829)
Inventors: Robert Dean; Raymond Bennett
Assignee: Individual (original assignee listed as Individual)
Key dates: Prior art date 1997-03-28; filing date 1999-11-19; granted/publication date 2000-12-05; anticipated expiration 2017-03-28. Legal status: Expired – Fee Related.
Purpose: To provide a low-cost, re-usable, non-volatile re-writable display that overcomes disadvantages of earlier systems — notably reliance on drive rollers, card-positioning sensors, thickness/wear-induced formatting errors, and moving parts — by mounting a measuring scale or indexing track integrally with an erasable, re-writable display material fixed to a carrier. A longitudinal axis of the scale is parallel to the direction of carrier movement relative to a terminal device, so humanly legible or graphic characters can be reliably and accurately positioned relative to the carrier and to permanently marked matter.
Plain-language scope: The invention combines (1) an unformatted display medium that accepts stimuli to create contrasting light/dark areas forming recognizable characters or graphics; (2) a writing means for stimulating, erasing, and rewriting the medium; and (3) an integrated coded pattern of indicia — a scale made from materials resistant to damage, corruption, and degradation — providing first-dimensional spatial formatting and direction-of-travel information for precise, repeatable positioning. A second, orthogonal dimension is formatted by the writing means, whose transducers are fixed relative to mechanical guiding features constraining a datum edge of the carrier. The permanent indexing track gives a continuous position reference, while a write head has an array of writing elements extending across the direction of travel for writing precisely positioned visible sequences in a single pass (e.g., a five-element dot-dash-dot-dash-dot array enabling seven-segment numerals 0–9). Figure descriptions cover a card read/write system, reference grid, pulse trains, card/display film views, indicia detectors, a shelf-edge label writing system, and an operation flow chart.
What the excerpt does not establish: It is a partial excerpt; much of the specification and the full claims are omitted, so exact claim scope, claim count, dependencies, and the complete detailed description are not established here. No prosecution history, validity, enforceability, ownership transfers, or litigation information is provided. The prior-art discussion is limited to the excerpted characterizations and should not be treated as an exhaustive or adjudicated record.
Generated 10/1/2026, 9:54:08 PM
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Litigation summary
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PTAB challenges
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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.