Invalidity dossier
US 5595099
Stress reduced pinned anvil and socket tool
Current assignee: Snap On Inc
Added 9/23/2026, 2:35:18 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 5,595,099 A
Title: "Stress reduced pinned anvil and socket tool"
Assignee/Applicant of record (per source): Originally filed by Snap On Technologies Inc; assignments recorded to Snap-On Incorporated, Snap-On Tools Worldwide, Inc., and Snap-On Technologies, Inc. Current assignees listed as Snap On Inc and Snap-on Tools Worldwide Inc. The source notes listed assignees may be inaccurate and that it performed no legal analysis.
Dates: Priority/filing date 1995-06-05 (application US08/460,916); granted and published 1997-01-21; anticipated expiration 2015-06-05; status "Expired - Lifetime." Inventor: Daniel S. Pusateri.
Purpose: Prior-art retention schemes weakened anvil drive lugs. A peripheral-ring friction fit (FIG. 2) wore out and would not reliably hold heavy sockets; transverse bores for a retaining pin (FIG. 3) or a spring-biased detent (FIG. 4) "severely weaken those lugs," with impact-wrench life testing reportedly showing an 80% decrease in anvil life versus a non-bored anvil. The invention aims to permanently or semi-permanently retain a socket tool on an anvil drive lug "without significantly weakening the drive lug" or creating undue stress concentration points.
Plain-language scope (from the supplied text): A socket tool body has a non-circular socket receptacle and a bore extending transversely through the body that intersects the receptacle along a chord, positioned to communicate with the anvil's existing circumferential groove when the drive lug is fully inserted. A pin is frictionally receivable through that bore and the groove to retain the socket tool on the anvil. The arrangement is stated to work with a prior-art anvil by removing its ring, and the tool may be an adapter (e.g., 1/2-inch to 3/4-inch drive) or an extension.
What the excerpt does not establish: It provides no issued claim numbers or full claim language, no complete figure descriptions, no prosecution history, no validity or infringement analysis, and no litigation or ownership-transfer information. Its prior-art discussion is the patent's own characterization.
Generated 10/1/2026, 9:52:09 PM
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Litigation summary
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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
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