Invalidity dossier
US 8523383
Retrofitting recessed lighting fixtures
Current assignee: Signify Holding BV
Added 9/23/2026, 12:24:56 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 8523383 B1
Title: Retrofitting recessed lighting fixtures
Patent number / application: US 8523383 B1; Application US13/031,448
Inventors: Valerica Grigore and Dean Grierson
Assignee history (as listed): Originally assigned to Cooper Technologies Company; later assignments recorded to Eaton Intelligent Power Limited and, currently listed, Signify Holding BV.
Key dates: Priority date 2010-02-19; filing date 2011-02-21; granted/publication date 2013-09-03; adjusted expiration listed as 2031-09-13. Status: Expired – Fee Related.
Purpose: The disclosure relates generally to lighting fixtures and, more particularly, to retrofitting recessed lighting fixtures. Retrofitting is described as replacing or eliminating components in an existing light fixture housing to improve energy efficiency or change another performance characteristic.
Plain-language scope (from the excerpt): A kit is provided for retrofitting a preexisting recessed light fixture housing mounted in a ceiling plane. The housing has an upper base panel and opposed end walls extending generally downward. The kit includes first and second mounting brackets coupled to the housing adjacent the opposed end walls, each bracket having an electrical socket. The sockets complete a circuit with a lamp—such as a fluorescent lamp, a linear LED lamp, and/or another lamp—when installed between them. A ballast powers the circuit and is configured to couple to the housing's upper base panel. An adhesive on a mounting side of the ballast provisionally mounts the ballast before a fastener permanently mounts it. The fastener may be captive hardware, pre-installed and movable only under deliberate force; each mounting bracket may also include captive hardware elements. The excerpt notes that pre-wiring the ballast to the sockets reduces required time and expertise. Figures 1–24 and a retrofitting method (FIG. 19) are referenced.
Source: https://patents.google.com/patent/US8523383/en
What the excerpt does not establish: It does not provide full claim language, the complete written description, exact claim scope, or the full method steps of FIG. 19. It does not establish litigation, validity, prior-art comparisons, or the accuracy of assignments/dates beyond the listed records.
Generated 10/1/2026, 9:53:38 PM
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Litigation summary
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Proceedings on file (0)
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PTAB challenges
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Assignment history
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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.