Invalidity dossier
US 2191954
Brake
Current assignee: Individual
Added 9/23/2026, 8:41:18 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 2,191,954 — "Brake"
Bibliographic data (from supplied text): Title, "Brake." Inventor: Ferdinand J. Buffa, Brooklyn, N.Y. Application No. 271,787, filed May 4, 1939; patent granted and published February 27, 1940. Original assignee and current assignee listed as "Individual." Prior-art date: May 4, 1939. Legal status shown as "Expired – Lifetime," with anticipated expiration February 27, 1957. Four claims; classified under B60T1/14 (braking elements acting directly on the road).
Purpose: The invention aims "to provide novel means for mounting, operating and controlling a flexible mat, adapted to be interposed between the rear wheels of a vehicle and the ground," to check the vehicle's progress and "prevent skidding of the vehicle on wet and ice-covered roadways." The device can be hand-operated or power-operated. The specification states it may be duplicated to any desired extent.
Plain-language scope: A trough-shaped casing is secured inside a fender, with transverse rollers journaled along its curved bottom and a hole in the front wall serving as a guide. A flexible mat — rubber or rubber compound, optionally reinforced with metal without impairing flexibility — rides on the rollers. A flexible element attached to the mat's rear shoulder runs over an idler, extends along the top of the mat to hold it on the rollers, and leads via further idlers to a handle near the driver's seat. A pull spring biases the mat to the retracted position; pulling the handle lowers the tapered mat until the wheel grips it against the ground, and a rigid stop engages the mat shoulder to limit downward/rearward travel and relieve strain on the spring. Figures 4–7 show modified forms, including a curved mat holder and U-shaped metal springs in the mat body, and a straight casing mounted under a running board with a slide.
Not established by this excerpt: The excerpt is incomplete and partially garbled; the full claim text, complete figure descriptions, and detailed operation of the modified embodiments (Figs. 4–7) are not fully legible above. It does not establish inventorship disputes, ownership transfers, validity, or prior art beyond the references named.
Generated 10/1/2026, 9:41:14 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.