diff --git a/src/applications/differential/field/specification/DifferentialCCsFieldSpecification.php b/src/applications/differential/field/specification/DifferentialCCsFieldSpecification.php
index 1af5fedd59..932b1c7bff 100644
--- a/src/applications/differential/field/specification/DifferentialCCsFieldSpecification.php
+++ b/src/applications/differential/field/specification/DifferentialCCsFieldSpecification.php
@@ -73,7 +73,7 @@ final class DifferentialCCsFieldSpecification
   }
 
   public function setValueFromParsedCommitMessage($value) {
-    $this->ccs = nonempty($value, array());
+    $this->ccs = array_unique(nonempty($value), array());
     return $this;
   }
 
diff --git a/src/applications/differential/field/specification/DifferentialManiphestTasksFieldSpecification.php b/src/applications/differential/field/specification/DifferentialManiphestTasksFieldSpecification.php
index 9ff4e8e860..4af92b55ec 100644
--- a/src/applications/differential/field/specification/DifferentialManiphestTasksFieldSpecification.php
+++ b/src/applications/differential/field/specification/DifferentialManiphestTasksFieldSpecification.php
@@ -92,7 +92,7 @@ final class DifferentialManiphestTasksFieldSpecification
   }
 
   public function setValueFromParsedCommitMessage($value) {
-    $this->maniphestTasks = nonempty($value, array());
+    $this->maniphestTasks = array_unique(nonempty($value), array());
     return $this;
   }
 
diff --git a/src/applications/differential/field/specification/DifferentialReviewersFieldSpecification.php b/src/applications/differential/field/specification/DifferentialReviewersFieldSpecification.php
index 45a20da245..fedc06df6f 100644
--- a/src/applications/differential/field/specification/DifferentialReviewersFieldSpecification.php
+++ b/src/applications/differential/field/specification/DifferentialReviewersFieldSpecification.php
@@ -91,7 +91,7 @@ final class DifferentialReviewersFieldSpecification
   }
 
   public function setValueFromParsedCommitMessage($value) {
-    $this->reviewers = nonempty($value, array());
+    $this->reviewers = array_unique(nonempty($value), array());
     return $this;
   }