Patent No. EP3802457 (titled "Dry Preparation Of Kaolin In The Production Of Hpa") was filed by SMS Group on Jun 11, 2019. The application was issued on Jan 26, 2022.

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 |
|---|---|---|
| GEBR PFEIFFER | Oct 26, 2022 | GRUNECKER PATENT |
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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