You will need it if you do an EPD for EPD Norge (now EPD Global) or EPD International. But in this case, you will also see the description of this indicator in the PCRs of the programme operators that you need for the modeling and result reporting rules. This indicator has the abbreviation GWP-IOBC/GHG.
We also have a description in the impact category description field (maybe not in the older versions), where we write:
Method: EF v3.1 EN15804 implementation from ecoinvent database v3.12, GWP-total but the biogenic carbon dioxide uptake ("Carbon dioxide, in air"), the biogenic carbon dioxide emissions ("Carbon dioxide, non-fossil") and the biogenic carbon dioxide correction ("Carbon dioxide, non-fossil, resource correction") is set to zero.
Impact category UUID: Taken from EPD International / ECO-Platform
This impact category is not part of the official EN15804 reference package, but is used in EPDs and sometimes called GWP-GHG (EPD International) or GWP-IOBC (EPD Norge / EPD Global). Because only one UUID number exists in the ILCD+EPD v1.2 MR6 format reported by the indata network (https://www.indata.network/resources) the UUID number for EN15804 EF 3.0 is taken from the ILCD+EPD v1.2 MR6 format and the UUID number for EN15804 EF 3.1 is taken from EPD International.