A new version of FLEXINVERT is now available for use with FLEXPART v11. The changes mostly affect the preprocessor prep_flexpart and the inversion source code. The capability of modelling total column footprints (needed for modelling satellite data) is not yet implemented in FLEXPART v11, so for this FLEXPART v10.4 is still needed. Note that this version of prep_flexpart is backwards compatible with FLEXPART v10.4.