Invalidity dossier
US 4727881
Biomedical electrode
Current assignee: 3M Co
Added 9/23/2026, 5:39:45 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 4,727,881
Title: Biomedical electrode
Patent number: US 4,727,881 A
Inventor(s): Lawrence W. Craighead; Clarence A. Niven
Original assignee: Minnesota Mining and Manufacturing Co. (current assignee listed as 3M Co.)
Prior art date: 1983-11-14
Filing date: 1986-05-21
Publication/grant date: 1988-03-01
Application number: US06/865,520
Legal status: Expired – Fee Related; anticipated expiration 2005-03-01
Source: https://patents.google.com/patent/US4727881/en
Purpose. The patent concerns disposable biomedical electrodes that connect human skin to an electromedical apparatus such as a high-impedance electromyograph, electrocardiograph, or electrostimulator for pain relief. It also covers an automated method of making such electrodes. The stated aim is to securely anchor a one-piece terminal member without washers or other retaining means mechanically biased against the post, simplifying manufacture without compromising mechanical integrity.
Plain-language scope. The electrode includes: (1) an electrical terminal member with a base (upper and lower major surfaces) and an integral upstanding post whose exposed surface connects directly to a lead wire; (2) a conformable, ionically conductive layer contacting the base's lower surface and extending peripherally beyond it; (3) a retainer sheet with an aperture spaced from its edge, dimensioned to receive and surround the post, extending beyond the base to positionally confine the terminal member between the retainer sheet and the conductive layer; and (4) a medical tape (backing plus pressure-sensitive adhesive) with a corresponding aperture. In a preferred embodiment, an electrically conductive metal or metallized layer sits between the retainer sheet and the base's upper surface and extends beyond the base periphery, improving conduction and reducing electrical noise. The manufacturing method includes cutting apertures in a release liner, laminating medical tape, cutting tape transversely, laminating retainer sheets, cutting holes, inserting terminal members, and laminating conductive layer pieces.
What the excerpt does not establish. The supplied text is expressly excerpted; the claim set, dependent claims, full specification, drawing details, and the complete method steps are not fully reproduced. It does not establish litigation, ownership transfers, validity, or prior-art determinations—these were not researched per the operating rules.
Generated 10/1/2026, 9:43:25 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
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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.