diff --git a/src/models/actions/CreateParticipant.ts b/src/models/actions/CreateParticipant.ts
index 9cd51ce..1bc45ac 100644
--- a/src/models/actions/CreateParticipant.ts
+++ b/src/models/actions/CreateParticipant.ts
@@ -17,7 +17,7 @@ export abstract class CreateParticipant {
      * Optional.
      */
     @IsString()
-    @IsNotEmpty()
+    @IsOptional()
     middlename?: string;
 
     /**