Problem statement- most of the times we need to find the list of rule overrides or OOTB rules which are overriden in the application.  

the existing utility to find the override rules is present in Application --> Development --> Rule Overrides, but this utility needs user to select the ruleset they think to be overriden, but this might be painful to find by going each and every ruleset. this existing utility wont give aggregate or overall rule wise count and details of rules. Solution-  PEGA provides one OOTB report definition rule which we can run directly to find overall rule sets override in the application, also by visiting each of ruleset we can in detail get which rule have override. Run Report definition RuleOverridesList  (Data-Rule-Summary), this does not requires any parameters.

after running this report definition rule (Note- this might take some time to run based on number of rulesets present in the application) we can expand the rule and click on rule which is overriden and get more details for that rule

On click it openmore details for that rule