Invalidity dossier
US 3389827
Easy-open container and sealing tape
Current assignee: 3M Co
Added 9/23/2026, 2:25:00 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: US3389827A
Title: Easy-open container and sealing tape
Patent number: US3389827A
Inventors: Joseph F Abere; Wilfred R Brochman
Original assignee: Minnesota Mining and Manufacturing Co
Current assignee (per listing): 3M Co
Key dates:
- Priority/filing date: 1967-04-10
- Publication (grant) date: 1968-06-25
- Anticipated expiration: 1985-06-25
- Legal status: Expired – Lifetime
Purpose (plain language): The patent concerns an easy-open container and a sealing tape. The source text indicates the subject matter relates to sealing methods and adhesive (pressure-sensitive adhesive) tapes used with containers, with the adhesive tape serving to seal a container while permitting it to be opened easily. The technical classification terms in the listing point to a pressure-sensitive adhesive tape having a backing, coated with an adhesive formulation, applied to seal a container.
Plain-language scope: Based on the supplied text, the patent discloses a container plus a sealing tape arrangement in which a pressure-sensitive adhesive tape is used to close the container and is intended to allow the container to be opened by hand (e.g., finger), i.e., an "easy-open" configuration. The disclosed adhesive chemistry categories referenced in the text include elastomers, resins, block copolymers, poly(chloroprene), styrene-butadiene and related vinyl/acrylic polymers, with solvents such as toluene, ethyl acetate, and 2-butanone. Backing materials referenced include plastic films (e.g., polyethylene terephthalate) and metals (e.g., aluminum, tinplate). The excerpt refers to coating methods, drying, and heat treatment.
What the excerpt does not establish: The supplied text does not include the actual claims, the full specification, the written description, drawings, or examples; it therefore does not establish the precise claimed scope, claim limitations, or the exact structural relationship between the tape and container. It also does not establish prosecution history, validity, infringement, ownership transfers, or litigation. For omitted text, consult the source.
Source: https://patents.google.com/patent/[US3389827](/patent/US3389827)/en
Generated 10/1/2026, 9:52:18 PM
Cases on file (0)
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Litigation summary
Past and pending lawsuits — plaintiffs, defendants, jurisdictions, outcomes, and notable rulings.
Proceedings on file (0)
All PTAB activity →AIA trial proceedings (IPR / PGR / CBM) filed at the USPTO Patent Trial and Appeal Board against this patent. Sourced from the USPTO Open Data Portal and refreshed every six hours; each proceeding number deep-links to the PTAB E2E docket.
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.