Patent No. EP4059904 (titled "A Process For The Continuous Preparation Of Alpha-Calcium Sulphate Hemihydrate And A Particulate Gypsum") was filed by Saint Gobain on Mar 19, 2021. The application was issued on Sep 6, 2023.

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 |
|---|---|---|
| KNAUF INSULATION | Jun 5, 2024 | MEISSNER BOLTE PARTNERSCHAFT MBB |
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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