Patent No. EP3581183 (titled "Tumor-Treating Pharmaceutical Composition") was filed by Eisai R&D Management on Feb 6, 2018. The application was issued on Nov 29, 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 |
|---|---|---|
| STADA ARZNEIMITTEL | Aug 29, 2024 | HAMM & WITTKOPP |
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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