Suggested mark to be worn by non-signatory nations

ICAN/CINA Resolutions 56 and 75 of 1923

Country Prefix Notes
GermanyD-Unofficially adopted. Officially allotted per Resolution 809
AfghanistanY-AOfficially adopted (Bulletin 12)
AlbaniaB-AOfficially adopted (Bulletin 5)
ArgentinaQ-AOfficially adopted the marks R-A (Bulletin 7)
AustriaA-OUnofficially adopted A-. Officially allotted OE- per Resolution 941
BulgariaQ-BOfficially adopted the marks B-B (Bulletin 5)
ChileB-COfficially adopted (Bulletin 8)
ColombiaT-CHK- Officially adopted (Resolution 507)
Costa RicaK-COfficially adopted (Bulletin 5)
Dominican RepublicZ-DOfficially adopted (Bulletin 12)
EsthoniaW-AOfficially adopted the marks E-A (Bulletin 6)
AbyssiniaA-BOfficially adopted (Bulletin 9)
FinlandV-FOfficially adopted the marks K-S (Bulletin 6)
LithuaniaZ-LOfficially adopted (Bulletin 6)
NorwayE-NUnofficially adopted N (which clashed with the USA). Officially allotted LN- per Resolution 624
ParaguayW-PZP- Officially adopted (Resolution 1019)
El SalvadorY-SOfficially adopted (Bulletin 11)
SwedenS-AOfficially adopted (Bulletin 5)
VenezuelaV-EYV- Officially adopted (Resolution 507)
Free City of DanzigY-MOfficially adopted (Bulletin 9)