  The search for novel topological phases of matter in quantum magnets has
emerged as a frontier of condensed matter physics. Here we use state-of-the-art
angle-resolved photoemission spectroscopy (ARPES) to investigate single
crystals of Co$_3$Sn$_2$S$_2$ in its ferromagnetic phase. We report for the
first time signatures of a topological Weyl loop. From fundamental symmetry
considerations, this magnetic Weyl loop is expected to be gapless if spin-orbit
coupling (SOC) is strictly zero but gapped, with possible Weyl points, under
finite SOC. We point out that high-resolution ARPES results to date cannot
unambiguously resolve the SOC gap anywhere along the Weyl loop, leaving open
the possibility that Co$_3$Sn$_2$S$_2$ hosts zero Weyl points or some non-zero
number of Weyl points. On the surface of our samples, we further observe a
possible Fermi arc, but we are unable to clearly verify its topological nature
using the established counting criteria. As a result, we argue that from the
point of view of photoemission spectroscopy the presence of Weyl points and
Fermi arcs in Co$_3$Sn$_2$S$_2$ remains ambiguous. Our results have
implications for ongoing investigations of Co$_3$Sn$_2$S$_2$ and other
topological magnets.
