Invalidity dossier
US 4292370
Moisture and temperature resistant polarizing lamination
Current assignee: Avery Dennison Corp
Added 9/23/2026, 2:57:23 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 — US4292370A
Title: Moisture and temperature resistant polarizing lamination
Patent number: US4292370A
Application number: US06/100,933
Inventor: John A. Pekko
Original assignee: Avery International Corp
Current assignee (as listed): Avery Dennison Corp
Priority/filing date: 1979-12-06
Publication (grant) date: 1981-09-29
Anticipated expiration: 1999-12-06
Legal status: Expired – Lifetime
Purpose and plain-language scope:
The supplied text identifies this as a moisture and temperature resistant polarizing lamination. Its key materials, per the keyword frequency listing, are polypropylene, polyvinyl alcohol, a polarizing film, and lamination, with adhesive and protective layers also appearing in the claims/abstract/description. Iodine appears in the claims, abstract and description, indicating an iodine-based polarizing element. The description mentions liquid crystal substances, suggesting use in liquid crystal displays, and lists substrate materials including Mylar™, cellulose acetate butyrate, cellulose triacetate, polyester, polyvinyl chloride, polycarbonate, polystyrene, glass, and aluminum foil. Bonding agents referenced include acrylic cement and urethane groups.
Classification data places it in G02F1/133528 (Polarisers) and related liquid crystal display construction classes, plus C09K2323/031 (Polarizer or dye) and various Y10T stock-material subclasses for adhesives and acrylic-derived polymers.
What the excerpt does not establish:
The supplied text is an excerpted Google Patents page. It does not include the full claims, the detailed description, or the drawings, so claim scope cannot be quoted or fully characterized. It does not establish a priority claim to any earlier application beyond the 1979-12-06 filing. It also does not establish current ownership with certainty — the page states listed assignees "may be inaccurate" and that legal status is "an assumption and is not a legal conclusion." No dates, jurisdictions, or specifics beyond those listed are confirmed.
Source: https://patents.google.com/patent/[US4292370](/patent/US4292370)/en
Generated 10/1/2026, 9:51:51 PM
Cases on file (0)
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Litigation summary
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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.