diff --git a/specification/synapse/data-plane/Microsoft.Synapse/stable/2020-12-01/entityTypes/Pipeline.json b/specification/synapse/data-plane/Microsoft.Synapse/stable/2020-12-01/entityTypes/Pipeline.json
index 694f6c3edc7f..70acb77317b4 100644
--- a/specification/synapse/data-plane/Microsoft.Synapse/stable/2020-12-01/entityTypes/Pipeline.json
+++ b/specification/synapse/data-plane/Microsoft.Synapse/stable/2020-12-01/entityTypes/Pipeline.json
@@ -3769,7 +3769,8 @@
       "properties": {
         "value": {
           "type": "object",
-          "description": "Stored procedure parameter value. Type: string (or Expression with resultType string)."
+          "description": "Stored procedure parameter value. Type: string (or Expression with resultType string).",
+          "x-nullable": true
         },
         "type": {
           "description": "Stored procedure parameter type.",