Patent No. EP3888833 (titled "Welding-Type Power Supply With Provision Of Feedback Based On Synergic Control Of A Welding-Type Output") was filed by Illinois Tool Works on Mar 16, 2021. The application was issued on Dec 4, 2024.

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 |
|---|---|---|
| EWM | Sep 4, 2025 | COHAUSZ & FLORACK |
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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