You want to apply the latest Oracle CPU patch to your Oracle home.
Oracle provides critical patch updates (CPUs) to its customers to fix known bugs that are critical in nature. These updates occur every quarter.
We suggest you shutdown SharePlex first, apply the CPU patch and startup SharePlex afterwards.
There are no known SharePlex implication when applying an Oracle CPU patch. SharePlex is just like any other Oracle application, as long as there are no certification issues, you just shutdown the Oracle clients/applications, make changes and then start up.
If you apply a "normal" Oracle patch (i.e. upgrade from 10.2.01 to 10.2.0.3) please consult our solution SOL21802 which provides information for an Oracle update.