Patent No. EP4121007 (titled "High Concentration Anti-Ass Protofibril Antibody Formulations And Methods Of Use Thereof") was filed by Eisai R&D Management on Mar 19, 2021. The application was issued on Jul 2, 2025.

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 |
|---|---|---|
| WUESTHOFF & WUESTHOFF | Apr 1, 2026 | SONNENHAUSER |
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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