Patent No. EP2651442 (titled "Universal Anti-Tag Chimeric Antigen Receptor-Expressing T Cells And Methods Of Treating Cancer") was filed by University OF Maryland on Dec 14, 2011. The application was issued on Apr 22, 2020.

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.
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.