diff --git a/docs/specs/clients/sign/rpc-methods.md b/docs/specs/clients/sign/rpc-methods.md
index 5c8aafb4..a4470de1 100644
--- a/docs/specs/clients/sign/rpc-methods.md
+++ b/docs/specs/clients/sign/rpc-methods.md
@@ -107,7 +107,7 @@ Used to settle a session over topic B.
       "events": [string]
     }
   }
-  "expiry": Int64, // seconds
+  "expiry": Int64, // milliseconds
 }
 
 | IRN     |          |