How to list applied patches with OPatch in Oracle

List the patches applied to an Oracle Home from the OS with OPatch. Set the environment (ORACLE_HOME, PATH) for the Home you want to inspect first.

# Full inventory (patches + bug list)
$ORACLE_HOME/OPatch/opatch lsinventory

# Concise patch list
$ORACLE_HOME/OPatch/opatch lspatches

# OPatch version itself
$ORACLE_HOME/OPatch/opatch version