The correspondence file
contains the list of all processes present in ecoinvent v2 and their equivalents (both activity and product names) in ecoinvent v3.
This file is helpful for understanding the re-naming of ecoinvent v2 datasets performed for ecoinvent v3 and therefore a resource for all tool and script users who want to adapt their software consistently. It also contains the UUIDs and the old ID numbers to match datasets easily. This file also contains information on the modifications of activities for v3, and information on which processes were not transferred (for various reasons) from ecoinvent v2 to ecoinvent v3. The change report
always explains such cases in more detail.