The M.23bs won both the 1929 Ostpreussenflug (Genet-powered) and the Circuit of Europe (Siemens Sh 13-powered) races.
The corresponding Romanian registers[REF][REF] show 26 more M.23bs, 14 of them locally built by ICAR (Intreprinderea de Constructii Aeronautice Romanesti, "Enterprise for Romanian Aeronautical Constructions") under licence from Messerschmitt.