diff --git a/include/ignition/transport/Discovery.hh b/include/ignition/transport/Discovery.hh
index accb789ee..9a9dda0f4 100644
--- a/include/ignition/transport/Discovery.hh
+++ b/include/ignition/transport/Discovery.hh
@@ -1405,12 +1405,10 @@ namespace ignition
       private: DiscoveryCallback<Pub> disconnectionCb;
 
       /// \brief Callback executed when a new remote subscriber is registered.
-      /// ToDo: Remove static when possible.
-      private: inline static DiscoveryCallback<Pub> registrationCb;
+      private: DiscoveryCallback<Pub> registrationCb;
 
       /// \brief Callback executed when a new remote subscriber is unregistered.
-      /// ToDo: Remove static when possible.
-      private: inline static DiscoveryCallback<Pub> unregistrationCb;
+      private: DiscoveryCallback<Pub> unregistrationCb;
 
       /// \brief Addressing information.
       private: TopicStorage<Pub> info;