diff --git a/specification/securityinsights/resource-manager/readme.md b/specification/securityinsights/resource-manager/readme.md
index bb3d2a02aae3..2ba35ef5cbaa 100644
--- a/specification/securityinsights/resource-manager/readme.md
+++ b/specification/securityinsights/resource-manager/readme.md
@@ -73,6 +73,19 @@ input-file:
   - Microsoft.SecurityInsights/preview/2024-04-01-preview/dataConnectorDefinitions.json
   - Microsoft.SecurityInsights/preview/2024-04-01-preview/dataConnectors.json
   - Microsoft.SecurityInsights/preview/2024-04-01-preview/operations.json
+suppressions:
+  - code: AvoidAdditionalProperties
+    from: Microsoft.SecurityInsights/preview/2024-04-01-preview/dataConnectors.json
+    reason: These properties are unknown and need to be specified by the customer (each request can have different values)
+  - code: AvoidAdditionalProperties
+    from: Microsoft.SecurityInsights/preview/2024-04-01-preview/Entities.json
+    reason: These properties are unknown and changed frequently (each request can have different values for each entity)
+  - code: AvoidAdditionalProperties
+    from: Microsoft.SecurityInsights/preview/2024-04-01-preview/EntityQueries.json
+    reason: These properties are unknown and changed frequently (each request can have different values for each entity)
+  - code: AvoidAdditionalProperties
+    from: Microsoft.SecurityInsights/preview/2024-04-01-preview/EntityQueryTemplates.json
+    reason: These properties are unknown and changed frequently (each request can have different values for each entity)
 ```
 ### Tag: package-2024-03