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The patent EP3821733 was granted to Daicel on Nov 22, 2023. The application was filed on Jul 13, 2018 under application number EP18926212A. The patent is currently recorded with a legal status of "Granted And Under Opposition".

Patent oppositions filed by competitors challenge the validity of a granted patent. These oppositions are typically based on claims of prior art, lack of novelty, or non-obviousness. They are a key part of the process for determining a patent's strength and enforceability.
| Company | Opposition Date | Representative | Opposition Status |
|---|---|---|---|
| PATENT ATTORNEYS WILHELM & BECK | Aug 21, 2024 | WALLINGER RICKER SCHLOTTER TOSTMANN | ADMISSIBLE |
Patent citations refer to prior patents cited during different phases such as opposition or international search.
| Citation Phase | Publication Number |
|---|---|
| DESCRIPTION | JP2015503335 |
| DESCRIPTION | WO2015136573 |
| INTERNATIONAL-SEARCH-REPORT | JP2010535024 |
| INTERNATIONAL-SEARCH-REPORT | JPS5831981 |
| INTERNATIONAL-SEARCH-REPORT | US2015128964 |
| INTERNATIONAL-SEARCH-REPORT | WO2013116558 |
| INTERNATIONAL-SEARCH-REPORT | WO2015136573 |
| OPPOSITION | CA624776 |
| OPPOSITION | GB892581 |
| OPPOSITION | JPS3914012B |
| OPPOSITION | US2017006912 |
| OPPOSITION | US2838364 |
| OPPOSITION | US3340571 |
| OPPOSITION | US4619279 |
| OPPOSITION | WO2013067511 |
| SEARCH | EP2921065 |
| SEARCH | EP3117724 |
| SEARCH | EP3225116 |
| SEARCH | JP2018035487 |
| SEARCH | US4619279 |
| SEARCH | WO2017148773 |
The dossier documents provide a comprehensive record of the patent's prosecution history - including filings, correspondence, and decisions made by patent offices - and are crucial for understanding the patent's legal journey and any challenges it may have faced during examination.
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Decision to grant a European patent
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Oct 18, 2023
(Electronic) Receipt
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Oct 18, 2023
French translation of claims
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Oct 18, 2023
German translation of the claims
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Oct 18, 2023
Letter accompanying subsequently filed items
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Intention to grant (signatures)
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Jun 23, 2023
Text intended for grant (clean copy)
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Mar 17, 2023
Examination started
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Oct 27, 2022
(Electronic) Receipt
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Oct 27, 2022
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Amended claims with annotations
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Amended description with annotations
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Oct 27, 2022
Amendments received before examination
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Oct 27, 2022
Letter accompanying subsequently filed items
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European search opinion
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Information on Search Strategy
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Supplementary European search report
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European search opinion
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Mar 14, 2022
Information on Search Strategy
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Mar 14, 2022
Supplementary European search report
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Feb 17, 2022
Search started
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Apr 21, 2021
Notification of forthcoming publication
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Mar 2, 2021
Communication to designated inventor
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Feb 24, 2021
(Electronic) Receipt
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Feb 24, 2021
Feb 24, 2021
Letter accompanying subsequently filed items
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Feb 24, 2021
Letter concerning the inventor
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Feb 23, 2021
Deficiencies in designation of inventor
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Feb 19, 2021
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(Electronic) Receipt
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Jan 21, 2021
Abstract
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Jan 21, 2021
Annex
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Jan 21, 2021
Claims
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Jan 21, 2021
Description
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Jan 21, 2021
Drawings
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Jan 21, 2021
Request for entry into the European phase
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Jan 21, 2021
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Information on entry into European phase
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Jan 21, 2020
Notification of election of EPO
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Jan 16, 2020
Copy of the international search report
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Jan 16, 2020
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International publication pamphlet
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