If CO₂ is sourced from the production or combustion of biofuels, bioliquids or biomass fuels, what certification approach should be applied in order for the CO₂ to be eligible for emissions from existing use or fate credits? 

The production or combustion site must be certified against RED as a Processing Unit for biofuel, bioliquid or biomass fuel production (ISCC EU). A separate Point of Origin certification for the CO₂ is not required in this case.

The existing RED certification demonstrates that the underlying biofuel, bioliquid or biomass fuel complies with the applicable RED sustainability and GHG-saving criteria. Provided that the CO₂ capture has not already received a credit for CO₂ capture and replacement, the captured CO₂ may qualify for eex-use credits.

The CO₂ is transferred to the next certified element in the supply chain with an ISCC Self-Declaration. If the CO₂ is subsequently purified, compressed or liquefied at a separate installation, that installation must be certified as a Processing Unit - Liquefaction Plant under ISCC EU and must forward the CO₂ with a Sustainability Declaration.