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The patent EP3977993 was granted to Pfizer on Jan 31, 2024. The application was filed on Aug 31, 2015 under application number EP21203965A. 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 |
|---|---|---|---|
| KELTIE | Oct 31, 2024 | KELTIE | ADMISSIBLE |
| QUIMICA SINTETICA | Oct 29, 2024 | AERA | ADMISSIBLE |
| QUIMICA SINTETICA | Oct 29, 2024 | BARDEHLE PAGENBERG SL | ADMISSIBLE |
Patent citations refer to prior patents cited during different phases such as opposition or international search.
| Citation Phase | Publication Number |
|---|---|
| DESCRIPTION | US5033252 |
| DESCRIPTION | US5052558 |
| DESCRIPTION | US5323907 |
| DESCRIPTION | US7214695 |
| DESCRIPTION | US8576985 |
| OPPOSITION | EP1587821 |
| OPPOSITION | WO2004056315 |
| SEARCH | US7214695 |
| SEARCH | WO2013038351 |
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.
Date
Description
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Decision to grant a European patent
Search/Exam
Dec 8, 2023
(Electronic) Receipt
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Dec 8, 2023
Filing of the translations of the claims
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Dec 8, 2023
French translation of claims
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Dec 8, 2023
German translation of the claims
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Sep 4, 2023
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Intention to grant (signatures)
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Sep 4, 2023
Text intended for grant (clean copy)
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Sep 4, 2023
Aug 14, 2023
(Electronic) Receipt
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Aug 14, 2023
Amended description with annotations
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Aug 14, 2023
Claims
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Aug 14, 2023
Description
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Aug 14, 2023
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Summary of subsequently filed documents
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Jun 12, 2023
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(Electronic) Receipt
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Jun 6, 2023
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Annex to the communication
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Mar 3, 2023
Communication from the Examining Division
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Feb 28, 2023
Letter accompanying subsequently filed items
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Feb 28, 2023
Feb 27, 2023
Examination started
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Sep 21, 2022
(Electronic) Receipt
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Sep 21, 2022
Amendments received before examination
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Sep 21, 2022
Amendments received before examination
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Sep 21, 2022
Letter accompanying subsequently filed items
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Sep 21, 2022
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Refund of fees
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Mar 10, 2022
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European search opinion
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Mar 10, 2022
European search report
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Mar 10, 2022
Information on Search Strategy
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Mar 10, 2022
Notification of forthcoming publication
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Oct 21, 2021
Abstract
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Oct 21, 2021
Oct 21, 2021
Claims
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Oct 21, 2021
Description
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Oct 21, 2021
Designation of inventor
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Oct 21, 2021
Drawings
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Oct 21, 2021
Letter concerning search matters
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Oct 21, 2021
Request for grant of a European patent
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Apr 5, 2016
Apr 5, 2016