diff --git a/libuavcan/include/uavcan/transport/dispatcher.hpp b/libuavcan/include/uavcan/transport/dispatcher.hpp
index bed9212eb1..69d6890077 100644
--- a/libuavcan/include/uavcan/transport/dispatcher.hpp
+++ b/libuavcan/include/uavcan/transport/dispatcher.hpp
@@ -41,6 +41,7 @@ class Dispatcher : Noncopyable
 
         bool add(TransferListenerBase* listener, Mode mode);
         void remove(TransferListenerBase* listener);
+        bool exists(DataTypeID dtid) const;
         void cleanup(MonotonicTime ts);
         void handleFrame(const RxFrame& frame);
 
@@ -79,6 +80,10 @@ public:
     void unregisterServiceRequestListener(TransferListenerBase* listener);
     void unregisterServiceResponseListener(TransferListenerBase* listener);
 
+    bool hasSubscriber(DataTypeID dtid) const;
+    bool hasPublisher(DataTypeID dtid) const;
+    bool hasServer(DataTypeID dtid) const;
+
     int getNumMessageListeners()         const { return lmsg_.getNumEntries(); }
     int getNumServiceRequestListeners()  const { return lsrv_req_.getNumEntries(); }
     int getNumServiceResponseListeners() const { return lsrv_resp_.getNumEntries(); }
diff --git a/libuavcan/src/transport/dispatcher.cpp b/libuavcan/src/transport/dispatcher.cpp
index 9851dc8fb9..a8e4ee035e 100644
--- a/libuavcan/src/transport/dispatcher.cpp
+++ b/libuavcan/src/transport/dispatcher.cpp
@@ -33,6 +33,18 @@ void Dispatcher::ListenerRegister::remove(TransferListenerBase* listener)
     list_.remove(listener);
 }
 
+bool Dispatcher::ListenerRegister::exists(DataTypeID dtid) const
+{
+    TransferListenerBase* p = list_.get();
+    while (p)
+    {
+        if (p->getDataTypeDescriptor().getID() == dtid)
+            return true;
+        p = p->getNextListNode();
+    }
+    return false;
+}
+
 void Dispatcher::ListenerRegister::cleanup(MonotonicTime ts)
 {
     TransferListenerBase* p = list_.get();
@@ -188,6 +200,22 @@ void Dispatcher::unregisterServiceResponseListener(TransferListenerBase* listene
     lsrv_resp_.remove(listener);
 }
 
+bool Dispatcher::hasSubscriber(DataTypeID dtid) const
+{
+    return lmsg_.exists(dtid);
+}
+
+bool Dispatcher::hasPublisher(DataTypeID dtid) const
+{
+    return outgoing_transfer_reg_.exists(dtid, TransferTypeMessageBroadcast)
+        || outgoing_transfer_reg_.exists(dtid, TransferTypeMessageUnicast);
+}
+
+bool Dispatcher::hasServer(DataTypeID dtid) const
+{
+    return lsrv_req_.exists(dtid);
+}
+
 bool Dispatcher::setNodeID(NodeID nid)
 {
     if (nid.isUnicast() && !self_node_id_.isValid())
diff --git a/libuavcan/test/transport/dispatcher.cpp b/libuavcan/test/transport/dispatcher.cpp
index 700111e360..fb862a0319 100644
--- a/libuavcan/test/transport/dispatcher.cpp
+++ b/libuavcan/test/transport/dispatcher.cpp
@@ -108,8 +108,15 @@ TEST(Dispatcher, Reception)
     };
 
     /*
-     * Sending the transfers
+     * Registration
      */
+    for (int i = 0; i < NUM_SUBSCRIBERS; i++)
+    {
+        ASSERT_FALSE(dispatcher.hasSubscriber(subscribers[i]->getDataTypeDescriptor().getID()));
+        ASSERT_FALSE(dispatcher.hasPublisher(subscribers[i]->getDataTypeDescriptor().getID()));
+        ASSERT_FALSE(dispatcher.hasServer(subscribers[i]->getDataTypeDescriptor().getID()));
+    }
+
     ASSERT_TRUE(dispatcher.registerMessageListener(subscribers[0].get()));
     ASSERT_TRUE(dispatcher.registerMessageListener(subscribers[1].get()));
     ASSERT_TRUE(dispatcher.registerMessageListener(subscribers[2].get()));
@@ -117,6 +124,20 @@ TEST(Dispatcher, Reception)
     ASSERT_TRUE(dispatcher.registerServiceResponseListener(subscribers[4].get()));
     ASSERT_TRUE(dispatcher.registerServiceResponseListener(subscribers[5].get()));
 
+    for (int i = 0; i < NUM_SUBSCRIBERS; i++)
+        ASSERT_FALSE(dispatcher.hasPublisher(subscribers[i]->getDataTypeDescriptor().getID()));
+
+    // Subscribers
+    ASSERT_TRUE(dispatcher.hasSubscriber(subscribers[0]->getDataTypeDescriptor().getID()));
+    ASSERT_TRUE(dispatcher.hasSubscriber(subscribers[1]->getDataTypeDescriptor().getID()));
+    ASSERT_TRUE(dispatcher.hasSubscriber(subscribers[2]->getDataTypeDescriptor().getID()));
+
+    // Servers
+    ASSERT_TRUE(dispatcher.hasServer(subscribers[3]->getDataTypeDescriptor().getID()));
+
+    /*
+     * Sending the transfers
+     */
     // Multiple service request listeners are not allowed
     ASSERT_FALSE(dispatcher.registerServiceRequestListener(subscribers[3].get()));
 
@@ -209,6 +230,13 @@ TEST(Dispatcher, Transmission)
     uavcan::Frame frame(123, uavcan::TransferTypeMessageUnicast, SELF_NODE_ID, 2, 0, 0, true);
     frame.setPayload(reinterpret_cast<const uint8_t*>("123"), 3);
 
+    ASSERT_FALSE(dispatcher.hasPublisher(123));
+    ASSERT_FALSE(dispatcher.hasPublisher(456));
+    const uavcan::OutgoingTransferRegistryKey otr_key(123, uavcan::TransferTypeMessageUnicast, 2);
+    ASSERT_TRUE(out_trans_reg.accessOrCreate(otr_key, uavcan::MonotonicTime::fromMSec(1000000)));
+    ASSERT_TRUE(dispatcher.hasPublisher(123));
+    ASSERT_FALSE(dispatcher.hasPublisher(456));
+
     ASSERT_EQ(2, dispatcher.send(frame, TX_DEADLINE, tsMono(0), uavcan::CanTxQueue::Volatile));
 
     /*