Invalidity dossier
US 5687940
Added 9/21/2026, 1:02:11 PM
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Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
Patent Overview — US5687940A
Title: Adjustable foot for upholstered furniture
Patent number: US5687940A
Application number: US08/589,402
Inventor: Rodney D. England
Assignee: England Corsair Upholstery Manufacturing Co., Inc. (original assignee; assignment recorded 1996-01-22, assigning interest from Rodney D. England)
Priority/filing date: 1996-01-22
Publication (grant) date: 1997-11-18
Status listed: Expired – Fee Related; anticipated expiration 2016-01-22
Source: https://patents.google.com/patent/[US5687940](/patent/US5687940)/en
Purpose: The patent addresses that upholstered furniture is built to preset specification and "remains virtually unchanged throughout its useful life," so any customer-desired revision "will require professional assistance." The invention provides an adjustable furniture foot and an adjustable-height upholstered seat, so seat height and fore-and-aft tilt can be changed without professional help.
Plain-language scope: A generally wedge-shaped foot has a thickness, a tapered first end terminating in a flat tab, and a wider second end with several holes and a curved lower portion that can rest solidly on a floor at various angles. A pin longer than the foot's thickness is inserted through a chosen hole so both pin ends protrude. The body sits in a slot in the frame's bottom, with the protruding pin lodged in grooves extending from either side of the slot and the first end extending below the frame outside the slot to form a foot. Choosing a different hole changes how far the foot extends below the frame, thereby adjusting seat height; using different holes at front versus rear feet tilts the seat forward or rearward (forward tilt is noted as aiding the elderly or infirm in rising). The description gives four identical feet, slots slightly wider than the feet, and nine seat orientations (FIGS. 3A–I). "Upholstered seat" is defined as sofas, loveseats, chairs, ottomans, chaise lounges and the like.
What the excerpt does not establish: The supplied text omits part of the background and any claims' full text; it shows no claim language beyond the abstract, no prior-art references, no examiner citations, and no litigation, ownership-transfer, or validity information. It provides no drawing images or reference numerals beyond those quoted, and no independent confirmation that the listed legal status is current or authoritative.
Generated 10/1/2026, 10:00:59 PM
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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
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.