Corollary 8.1.3.11. Let $\operatorname{\mathcal{C}}$ be a Kan complex. Then the simplicial set $\operatorname{Cospan}(\operatorname{\mathcal{C}})$ is also a Kan complex.
$\Newextarrow{\xhookrightarrow}{10,10}{0x21AA}$
Proof. Apply Corollary 8.1.3.10 in the special case $\operatorname{\mathcal{D}}= \Delta ^0$. $\square$