Easy way to find patch version is use opatch application
Example:
$ORACLE_HOME/OPatch/opatch lsinventory
example of output
/export/home/oracle> [oracle@atlantisoracle ~]$ opatch lsinventory Oracle Interim Patch Installer version 11.2.0.3.15 Copyright (c) 2017, Oracle Corporation. All rights reserved. Oracle Home : /export/home/oracle/app/11gr2 Central Inventory : /export/home/oracle/oraInventory from : /export/home/oracle/app/11gr2/oraInst.loc OPatch version : 11.2.0.3.15 OUI version : 11.2.0.3.0 Log file location : /export/home/oracle/app/11gr2/cfgtoollogs/opatch/opatch2017-07-18_13-46-41PM_1.log Lsinventory Output file location : /export/home/oracle/app/11gr2/cfgtoollogs/opatch/lsinv/lsinventory2017-07-18_13-46-41PM.txt
Below will be a list of current patches
To find this same information from inside the database, there are a two views that can be used.
Example:
SQL> select * from sys.v$version ; BANNER -------------------------------------------------------------------------------- Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production PL/SQL Release 11.2.0.3.0 - Production CORE 11.2.0.3.0 Production TNS for Solaris: Version 11.2.0.3.0 - Production NLSRTL Version 11.2.0.3.0 - Production
SQL>select * from sys.registry$history;
This view will display you a history of patches.