Umbra Lab, USA
https://umbra.space/
Umbra-01, #48906 2.254GHz FM, inactive
Umbra-02, #50986 2.254GHz FM, inactive
Umbra-03, #52753 2.254GHz FM, inactive
Umbra-04, #55050 2.254GHz FM, unknown
Umbra-05, #55036 2.254GHz FM, unknown
Umbra-06, #56189 2.254GHz FM, unknown