Invalidity dossier
US 8419223
LED tube to replace fluorescent tube
Current assignee: Individual
Added 9/23/2026, 2:26:05 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 8,419,223 B2
Title: LED tube to replace fluorescent tube
Patent number: US 8,419,223 B2
Application number: US 12/766,449
Inventor: Billy V. Withers
Assignee: Individual (original and current assignee listed as "Individual")
Priority date: 2009-04-23
Filing date: 2010-04-23
Publication date: 2013-04-16 (application published as US 2010/0270925 A1 on 2010-10-28)
Legal status: Expired – Fee Related; adjusted expiration listed as 2031-05-29
Purpose: The patent addresses the large installed base of fluorescent light fixtures, noting that removing every fixture would be enormously expensive. It seeks to provide an LED light that replaces fluorescent tubes in a typical fluorescent luminary without replacing the luminary or other fixture components. It states LED light sources are desirable for extremely long life and far lower power use than equivalent fluorescent tubes.
Plain-language scope (from the supplied excerpt): The invention is an LED lighting tube configured to replace fluorescent tubes such as T-8, T12, or T5 in a fluorescent tube fixture. It includes a tube body with a long axis, with first and second dummy end caps having electrode pins proportioned to fit a standard fluorescent fixture but electrically non-active. A heat sink base plate (preferably aluminum, generally rectangular) attaches to the dummy end caps. LED light sources are attached to a first side of the base plate and directed away from it, possibly at angles. A translucent diffuser plate is mounted above the LEDs and held by support posts. A light driver supplies power via power leads attached to the heat sink base at an attachment point between the dummy end caps. The tube cover may be transparent plastic or glass, generally cylindrical or U-shaped in cross section. A dimmer switch may be used. The electrical connection enters through a positive connection point rather than the end electrodes.
What the excerpt does not establish: It is an excerpt only; omitted text and the full claims are not provided (the claims section was not included). It therefore does not establish the precise claimed scope, dependencies, or limitations. It does not establish litigation, ownership transfers, validity, or prior art beyond the listed classifications.
Generated 10/1/2026, 9:52:16 PM
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Litigation summary
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Proceedings on file (0)
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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.