Patent No. EP3990777 (titled "Controlling Power Output Of A Wind Turbine At Below-Rated Wind Speed") was filed by Vestas Wind Systems on Jun 22, 2020. The application was issued on Jun 7, 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 |
|---|---|---|
| NORDEX ENERGY | Mar 6, 2024 | EPPING HERMANN FISCHER |
| NORDEX ENERGY | Mar 6, 2024 | VOLKL SIEBENSON PATENTANWALTE 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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