diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7930ef20f00e0ed9fd5580662a051da5ab82fc87..145d1b1d5b4418c7fdf917ddf9f54d0257418efd 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,7 @@
 # Version 1.76 (not yet released)
 
 * Added permission 'access dataprocessor definitions' that facilitates reading the DataProcessor Output Definitions without granting access CiviCRM. Created for the [Drupal CMRF Reference module](https://www.drupal.org/project/cmrf_reference).
+* Fix for aggregate on case for activities.
 
 # Version 1.75
 
diff --git a/Civi/DataProcessor/Source/Activity/ActivitySource.php b/Civi/DataProcessor/Source/Activity/ActivitySource.php
index 334f07e543b3b396e4203d7af51c4692339d2bf5..1987d8605863fe2d12dc84850a0f3eaaf839239f 100644
--- a/Civi/DataProcessor/Source/Activity/ActivitySource.php
+++ b/Civi/DataProcessor/Source/Activity/ActivitySource.php
@@ -179,6 +179,8 @@ class ActivitySource extends AbstractCivicrmEntitySource {
       $field->alias = $aggregate_by;
       if (stripos($field->name, 'activity_contact_') === 0) {
         $field->name = substr($field->name, 17);
+      } elseif  (stripos($field->name, 'activity_case_') === 0) {
+        $field->name = str_replace('activity_case_', '', $field->name);
       }
       $groupByFields[] = $field;
     }
@@ -247,7 +249,7 @@ class ActivitySource extends AbstractCivicrmEntitySource {
       if (stripos($field->name, 'activity_contact_')===0) {
         return $this->activityAggregationContactDataFlow;
       } elseif (stripos($field->name, 'activity_case_')===0) {
-        return $this->activityAggregationContactDataFlow;
+        return $this->activityAggregationCaseDataFlow;
       }
       return $this->activityAggregationDataFlow;
     }