You will get something like this on your "opatch lsinventory" Installed Top-level Products (5): Oracle Client 10.2.0.1.0 Oracle Database 10g 10.2.0.1.0 Oracle Database 10g Products 10.2.0.1.0 <-- this is the companion Oracle Database 10g Release 2 Patch Set 2 10.2.0.3.0 Oracle Database Vault 10.2.0.3.0 There are 5 products installed in this Oracle Home.