diff --git a/docs/configuration/backends/servicefabric.md b/docs/configuration/backends/servicefabric.md
index 563849dd5..09140bad5 100644
--- a/docs/configuration/backends/servicefabric.md
+++ b/docs/configuration/backends/servicefabric.md
@@ -69,6 +69,8 @@ Here is an example of an extension setting Traefik labels:
 </StatelessServiceType>
 ```
 
+> **Note**: The `Label` tag and its `Key` attribute are case sensitive. That is, if you use `label` instead of `Label` or `key` instead of `Key`, they will be silently ignored.
+
 #### Property Manager
 
 Set Labels with the property manager API to overwrite and add labels, while your service is running.