It is a 7-Zip compressed archive (.7z), typically used to bundle multiple related documents into a single download.
According to the public records on AsktheEU.org , this specific file is part of a disclosure regarding meetings between EU officials and corporations like and Eastman Chemical concerning circular economy policies. 6364.7z
It is associated with case GestDem 2022/6364 , which pertains to a "partial access" decision where certain documents were released while others remained protected or redacted. It is a 7-Zip compressed archive (