SN 2001bt was discovered by R. Chassagne. The position is 27".7
west and 17".1 north from the center of the host galaxy.
The host galaxy IC 4380 is a barred-spiral galaxy, and the SN is
superimposed on the disk region. The expected maximum of SN Ia is mag
about 15.5, but the discovery magnitude (15.0mag) is exceed it