  The observations of gravitational waves (GWs) have revealed the existence of
black holes (BHs) above $30M_\odot$. A variety of scenarios have been proposed
as their origin. Among the scenarios, we consider the population III (Pop~III)
star scenario. In this scenario, binary black holes (BBHs) containing such
massive BHs are naturally produced. We consider Pop~I/II field binaries,
Pop~III field binaries and the binaries dynamically formed in globular
clusters. We employ a hierarchical Bayesian analysis method and constrain the
branching fraction of each formation channel in our universe by using the
LIGO-Virgo-KAGRA gravitational wave transient catalog (GWTC-3) events. We find
that the Pop~I/II field binary channel dominates the entire merging BBHs. We
obtain the branching fraction of the Pop~III BBH channel of
$0.11^{+0.08}_{-0.06}$, which gives the consistent local merger rate density
with the model of Pop~III BBH scenario we adopt. We confirm that BHs arising
from the Pop~III channel contribute to massive BBHs in GWTC-3. We also evaluate
the branching fraction of each formation channel in the observed BBHs in the
GWTC-3 and find the near-equal contributions from the three channels.
