diff --git a/internal/dataexchange/ffdx/dxevent.go b/internal/dataexchange/ffdx/dxevent.go
index cf91e3e08d..b125fe7b26 100644
--- a/internal/dataexchange/ffdx/dxevent.go
+++ b/internal/dataexchange/ffdx/dxevent.go
@@ -17,6 +17,8 @@
 package ffdx
 
 import (
+	"strings"
+
 	"github.com/hyperledger/firefly-common/pkg/fftypes"
 	"github.com/hyperledger/firefly-common/pkg/i18n"
 	"github.com/hyperledger/firefly-common/pkg/log"
@@ -154,8 +156,10 @@ func (h *FFDX) dispatchEvent(msg *wsEvent) {
 		var hash *fftypes.Bytes32
 		hash, err = fftypes.ParseBytes32(h.ctx, msg.Hash)
 		if err == nil {
+			pathParts := strings.Split(msg.Path, "/")
 			e.dxType = dataexchange.DXEventTypePrivateBlobReceived
 			e.privateBlobReceived = &dataexchange.PrivateBlobReceived{
+				Namespace:  pathParts[0],
 				PeerID:     msg.Sender,
 				Hash:       *hash,
 				Size:       msg.Size,
diff --git a/internal/dataexchange/ffdx/ffdx.go b/internal/dataexchange/ffdx/ffdx.go
index 1447a27933..eed9b14b79 100644
--- a/internal/dataexchange/ffdx/ffdx.go
+++ b/internal/dataexchange/ffdx/ffdx.go
@@ -39,7 +39,7 @@ import (
 type FFDX struct {
 	ctx          context.Context
 	capabilities *dataexchange.Capabilities
-	callbacks    dataexchange.Callbacks
+	callbacks    callbacks
 	client       *resty.Client
 	wsconn       wsclient.WSClient
 	needsInit    bool
@@ -49,6 +49,16 @@ type FFDX struct {
 	ackChannel   chan *ack
 }
 
+type callbacks struct {
+	listeners []dataexchange.Callbacks
+}
+
+func (cb *callbacks) DXEvent(event dataexchange.DXEvent) {
+	for _, cb := range cb.listeners {
+		cb.DXEvent(event)
+	}
+}
+
 const (
 	dxHTTPHeaderHash = "dx-hash"
 	dxHTTPHeaderSize = "dx-size"
@@ -138,8 +148,8 @@ func (h *FFDX) SetNodes(nodes []fftypes.JSONObject) {
 	h.nodes = nodes
 }
 
-func (h *FFDX) RegisterListener(callbacks dataexchange.Callbacks) {
-	h.callbacks = callbacks
+func (h *FFDX) RegisterListener(listener dataexchange.Callbacks) {
+	h.callbacks.listeners = append(h.callbacks.listeners, listener)
 }
 
 func (h *FFDX) Start() error {
diff --git a/internal/dataexchange/ffdx/ffdx_test.go b/internal/dataexchange/ffdx/ffdx_test.go
index 04281bdbfc..25a37476dd 100644
--- a/internal/dataexchange/ffdx/ffdx_test.go
+++ b/internal/dataexchange/ffdx/ffdx_test.go
@@ -443,7 +443,7 @@ func TestEvents(t *testing.T) {
 	assert.Equal(t, `{"action":"ack","id":"0"}`, string(msg))
 
 	mcb := &dataexchangemocks.Callbacks{}
-	h.callbacks = mcb
+	h.RegisterListener(mcb)
 
 	mcb.On("DXEvent", mock.MatchedBy(func(ev dataexchange.DXEvent) bool {
 		return ev.NamespacedID() == "1" &&
@@ -557,7 +557,7 @@ func TestEventsWithManifest(t *testing.T) {
 	assert.Equal(t, `{"action":"ack","id":"0"}`, string(msg))
 
 	mcb := &dataexchangemocks.Callbacks{}
-	h.callbacks = mcb
+	h.RegisterListener(mcb)
 
 	mcb.On("DXEvent", mock.MatchedBy(func(ev dataexchange.DXEvent) bool {
 		return ev.NamespacedID() == "1" &&
@@ -585,7 +585,7 @@ func TestEventLoopReceiveClosed(t *testing.T) {
 	wsm := &wsmocks.WSClient{}
 	h := &FFDX{
 		ctx:       context.Background(),
-		callbacks: dxc,
+		callbacks: callbacks{listeners: []dataexchange.Callbacks{dxc}},
 		wsconn:    wsm,
 	}
 	r := make(chan []byte)
@@ -601,7 +601,7 @@ func TestEventLoopSendClosed(t *testing.T) {
 	ctx, cancelCtx := context.WithCancel(context.Background())
 	h := &FFDX{
 		ctx:        ctx,
-		callbacks:  dxc,
+		callbacks:  callbacks{listeners: []dataexchange.Callbacks{dxc}},
 		wsconn:     wsm,
 		ackChannel: make(chan *ack, 1),
 	}
@@ -622,7 +622,7 @@ func TestEventLoopClosedContext(t *testing.T) {
 	cancel()
 	h := &FFDX{
 		ctx:       ctx,
-		callbacks: dxc,
+		callbacks: callbacks{listeners: []dataexchange.Callbacks{dxc}},
 		wsconn:    wsm,
 	}
 	r := make(chan []byte, 1)
diff --git a/internal/events/dx_callbacks.go b/internal/events/dx_callbacks.go
index 1b91174bcd..a873fa9472 100644
--- a/internal/events/dx_callbacks.go
+++ b/internal/events/dx_callbacks.go
@@ -185,7 +185,7 @@ func (em *eventManager) messageReceived(dx dataexchange.Plugin, event dataexchan
 
 	mr := event.MessageReceived()
 
-	// De-serializae the transport wrapper
+	// De-serialize the transport wrapper
 	var wrapper *core.TransportWrapper
 	err := json.Unmarshal(mr.Data, &wrapper)
 	if err != nil {
@@ -198,6 +198,10 @@ func (em *eventManager) messageReceived(dx dataexchange.Plugin, event dataexchan
 		event.AckWithManifest("")
 		return
 	}
+	if wrapper.Batch.Namespace != em.namespace {
+		log.L(em.ctx).Debugf("Ignoring batch from wrong namespace '%s'", wrapper.Batch.Namespace)
+		return
+	}
 	l.Infof("Private batch received from %s peer '%s' (len=%d)", dx.Name(), mr.PeerID, len(mr.Data))
 
 	manifestString, err := em.privateBatchReceived(mr.PeerID, wrapper.Batch, wrapper.Group)
@@ -218,6 +222,10 @@ func (em *eventManager) privateBlobReceived(dx dataexchange.Plugin, event dataex
 		event.Ack() // Still confirm the event
 		return
 	}
+	if br.Namespace != em.namespace {
+		log.L(em.ctx).Debugf("Ignoring blob from wrong namespace '%s'", br.Namespace)
+		return
+	}
 
 	// Dispatch to the blob receiver for efficient batch DB operations
 	em.blobReceiver.blobReceived(em.ctx, &blobNotification{
diff --git a/internal/events/dx_callbacks_test.go b/internal/events/dx_callbacks_test.go
index d64c323467..a24840d86a 100644
--- a/internal/events/dx_callbacks_test.go
+++ b/internal/events/dx_callbacks_test.go
@@ -20,6 +20,7 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
+	"strings"
 	"testing"
 
 	"github.com/hyperledger/firefly-common/pkg/fftypes"
@@ -99,7 +100,9 @@ func newMessageReceived(peerID string, data []byte, expectedManifest string) *da
 
 func newPrivateBlobReceivedNoAck(peerID string, hash *fftypes.Bytes32, size int64, payloadRef string) *dataexchangemocks.DXEvent {
 	mde := &dataexchangemocks.DXEvent{}
+	pathParts := strings.Split(payloadRef, "/")
 	mde.On("PrivateBlobReceived").Return(&dataexchange.PrivateBlobReceived{
+		Namespace:  pathParts[0],
 		PeerID:     peerID,
 		Hash:       *hash,
 		Size:       size,
diff --git a/internal/identity/tbd/tbd.go b/internal/identity/tbd/tbd.go
index 507d8aedf0..197d9269c6 100644
--- a/internal/identity/tbd/tbd.go
+++ b/internal/identity/tbd/tbd.go
@@ -26,7 +26,6 @@ import (
 // TBD is a null implementation of the Identity Interface to avoid breaking configuration created with the previous "onchain" plugin
 type TBD struct {
 	capabilities *identity.Capabilities
-	callbacks    identity.Callbacks
 }
 
 func (tbd *TBD) Name() string {
@@ -38,8 +37,7 @@ func (tbd *TBD) Init(ctx context.Context, config config.Section) (err error) {
 	return nil
 }
 
-func (tbd *TBD) RegisterListener(callbacks identity.Callbacks) {
-	tbd.callbacks = callbacks
+func (tbd *TBD) RegisterListener(listener identity.Callbacks) {
 }
 
 func (tbd *TBD) Start() error {
diff --git a/internal/sharedstorage/ipfs/ipfs.go b/internal/sharedstorage/ipfs/ipfs.go
index e9d4d12020..a7d878ca48 100644
--- a/internal/sharedstorage/ipfs/ipfs.go
+++ b/internal/sharedstorage/ipfs/ipfs.go
@@ -35,7 +35,6 @@ import (
 type IPFS struct {
 	ctx          context.Context
 	capabilities *sharedstorage.Capabilities
-	callbacks    sharedstorage.Callbacks
 	apiClient    *resty.Client
 	gwClient     *resty.Client
 }
@@ -68,8 +67,7 @@ func (i *IPFS) Init(ctx context.Context, config config.Section) error {
 	return nil
 }
 
-func (i *IPFS) RegisterListener(callbacks sharedstorage.Callbacks) {
-	i.callbacks = callbacks
+func (i *IPFS) RegisterListener(listener sharedstorage.Callbacks) {
 }
 
 func (i *IPFS) Capabilities() *sharedstorage.Capabilities {
diff --git a/pkg/dataexchange/plugin.go b/pkg/dataexchange/plugin.go
index bdb6e7ff38..3a6db6e4ff 100644
--- a/pkg/dataexchange/plugin.go
+++ b/pkg/dataexchange/plugin.go
@@ -67,7 +67,7 @@ type Plugin interface {
 	SetNodes(nodes []fftypes.JSONObject)
 
 	// RegisterListener registers a listener to receive callbacks
-	RegisterListener(callbacks Callbacks)
+	RegisterListener(listener Callbacks)
 
 	// Data exchange interface must not deliver any events until start is called
 	Start() error
@@ -129,6 +129,7 @@ type MessageReceived struct {
 }
 
 type PrivateBlobReceived struct {
+	Namespace  string
 	PeerID     string
 	Hash       fftypes.Bytes32
 	Size       int64
diff --git a/pkg/identity/plugin.go b/pkg/identity/plugin.go
index 6f250e6002..59c9f5248d 100644
--- a/pkg/identity/plugin.go
+++ b/pkg/identity/plugin.go
@@ -34,7 +34,7 @@ type Plugin interface {
 	Init(ctx context.Context, config config.Section) error
 
 	// RegisterListener registers a listener to receive callbacks
-	RegisterListener(callbacks Callbacks)
+	RegisterListener(listener Callbacks)
 
 	// Blockchain interface must not deliver any events until start is called
 	Start() error
diff --git a/pkg/sharedstorage/plugin.go b/pkg/sharedstorage/plugin.go
index 1045353ea5..4c65855125 100644
--- a/pkg/sharedstorage/plugin.go
+++ b/pkg/sharedstorage/plugin.go
@@ -35,7 +35,7 @@ type Plugin interface {
 	Init(ctx context.Context, config config.Section) error
 
 	// RegisterListener registers a listener to receive callbacks
-	RegisterListener(callbacks Callbacks)
+	RegisterListener(listener Callbacks)
 
 	// Capabilities returns capabilities - not called until after Init
 	Capabilities() *Capabilities