TITLE: GCN CIRCULAR NUMBER: 20762 SUBJECT: LIGO/Virgo G275404: Keck LRIS classification of MASTER PSN candidate DATE: 17/02/27 18:59:08 GMT FROM: Mansi M. Kasliwal at Caltech N. Blagorodnova (Caltech), A. Ho (Caltech), T. Hung (UMd), K. Vyhmeister (Caltech), S. R. Kulkarni (Caltech), D. Cook (Caltech), A. van Sistine (UW Milwaukee) and M. M. Kasliwal (Caltech) report on behalf of the iPTF and GROWTH collaborations We observed the transient MASTER PSN reported in LVC GCN #20759, using LRIS on the Keck I Telescope, on 2017-02-26 at 05:45 UT. The spectrum shows relatively broad features at z=0.017. A SNID fit is consistent with a Type Ic (possibly Ic broad-line) a month after maximum light. The host galaxy, which does not have a previously known spectroscopic redshift, is also a line emitter in the CLU (Census of the Local Universe; Cook et al. 2017) narrow-band redshifted Halpha imaging, consistent with being local.