Is Relinking Of Oracle (Relink All) Required After Patching OS?

Applies to:
Oracle Server - Enterprise Edition - Version: 9.2.0.0 to 10.2.0.2
Information in this document applies to any platform.
GoalIs
relinking of Oracle binaries required after upgrading or patching of OS?
In Metalink Certify section says that it is not required.
"General Notes For Oracle Database - Enterprise Edition:
O/S Information:
The vendors guarantee operating system binary compatibility; therefore, no
reinstall or relink of the Oracle software is required when upgrading these
operating systems unless specifically stated otherwise."

Now why relinking is required after OS upgrade/patching?

Solution
Oracle software come as object files or source files which generally get relinked with OS
libraries at the time of installation to get the executables.
If you upgrade or apply the patches to the operating system, the libraries which are linked with
oracle binaries may be get updated. Ideally speaking there should not be any problem because
updated libraries also would work fine with Oracle binaries as OS vendors maintain backward
compatibility. This is only specified as "The vendors guarantee operating system binary
compatibility".
But in some cases it is possible that new libraries may not compatible with old libraries (because
of bug in OS libraries itself).
In some cases it is also possible that Oracle software may not work with new libraries as it may
take advantage of a flaw in old OS libraries which is fixed new OS libraries.
In some cases because of bug in Oracle software itself it may not work as expected with new
libraries.
So, to ensure that Oracle software is not broken with updated libraries, it is recommended to
relink the Oracle binaries even though ideally it is not required.

ReferencesNote 131321.1 - How to Relink Oracle Database Software on UNIX