diff --git a/README.md b/README.md
index 8a16f54..c10c931 100644
--- a/README.md
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@@ -2,6 +2,8 @@
 
 Minimal Delegated License Service (DLS).
 
+Compatibility tested with official DLS 2.0.1.
+
 This service can be used without internet connection.
 Only the clients need a connection to this service on configured port.