How to find out which weblogic server version installed on the machine

1

From registry.xml in MW_HOME
Go to Middleware Home under which WebLogic is installed and look for file registry.xml
Open registry.xml and search for “component name=”WebLogic Server”” version=”10.3.3.0″  (variable version next to this will tell you weblogic version)

Also  you can see:
release level="10.2" ServicePackLevel="0" PatchLevel="0"
it is  version and patch level of the server,  i am not very sure

2
Go to $WL_HOME/server/lib
Run the following command:

ex: mine is  C:\bea\wlserver_10.0\server\lib

$ java -cp weblogic.jar weblogic.version

$ java -cp weblogic.jar weblogic.version -verbose

$ java -cp weblogic.jar weblogic.utils.Versions