Invalidity dossier
US 4640289
Biomedical electrode
Current assignee: 3M Co
Added 9/23/2026, 4:49:14 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 4,640,289
Title: Biomedical electrode
Inventor: Lawrence W. Craighead
Original Assignee: Minnesota Mining and Manufacturing Co. (listed current assignee: 3M Co.)
Application No.: US 06/551,069
Priority/Filing Date: 1983-11-14
Publication (Grant) Date: 1987-02-03
Legal Status (as listed): Expired – Lifetime (anticipated expiration 2004-02-03)
Source: https://patents.google.com/patent/US4640289/en
Purpose
The invention relates to disposable biomedical electrodes for electrically connecting human skin to an electromedical apparatus such as a high-impedance electromyograph, electrocardiograph, or electrostimulator for pain relief.
Plain-language scope
The electrode has three cooperating parts: (1) a one-piece electrical terminal member with a base and an integral post extending from the base's upper surface, the post's exposed surface providing direct physical and electrical connection to a lead wire; (2) a conformable, ionically conductive layer in contact with the base's lower surface and extending peripherally beyond the base; and (3) a retainer sheet with an aperture spaced from its edge, sized to receive and surround the post. The retainer sheet extends outwardly beyond the base and contacts both the ionically conductive layer and the terminal member, positionally confining the terminal member between the retainer sheet and the conductive layer.
The stated advantage is that the retainer sheet anchors the one-piece terminal member without washers or other retaining means mechanically biased against the post, simplifying manufacture. The retainer resists tearing and stretching so the base cannot pass through the aperture under normal use forces. In a preferred embodiment, an electrically conductive metal or metallized layer lies between the retainer sheet and the base's upper surface, extending beyond the base periphery to improve conduction and reduce electrical noise. A medical tape with a pressure-sensitive adhesive and a post-receiving aperture, plus protective release liners, may also be included. FIGS. 1–3 show a strip of electrodes, a cross-section, and a manufacturing method.
What the excerpt does not establish
The supplied text is an excerpt: full claims, the complete written description, all drawing details, and the full prior-art discussion are omitted. It therefore does not establish the exact claim scope, the full list of cited references, or any litigation, ownership transfer, or validity matters (not researched per instruction).
Generated 10/1/2026, 9:44:08 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.