diff --git a/cmd/unified/main.go b/cmd/unified/main.go
index b14dccf..dec0654 100644
--- a/cmd/unified/main.go
+++ b/cmd/unified/main.go
@@ -257,6 +257,10 @@ func fileRoutes(mux *http.ServeMux, store filesvc.MeshStore, blobs blobfs.Store)
 		}
 		it, err := store.Rename(r.Context(), in.ID, in.Name)
 		if err != nil {
+			if errors.Is(err, filesvc.ErrForbidden) {
+				writeJSON(w, http.StatusForbidden, map[string]string{"error": "only owner may modify"})
+				return
+			}
 			status := http.StatusBadRequest
 			if errors.Is(err, filesvc.ErrNotFound) {
 				status = http.StatusNotFound
@@ -283,6 +287,10 @@ func fileRoutes(mux *http.ServeMux, store filesvc.MeshStore, blobs blobfs.Store)
 		it, err := store.Delete(r.Context(), in.ID)
 		_ = blobs.Delete(r.Context(), string(in.ID))
 		if err != nil {
+			if errors.Is(err, filesvc.ErrForbidden) {
+				writeJSON(w, http.StatusForbidden, map[string]string{"error": "only owner may modify"})
+				return
+			}
 			status := http.StatusBadRequest
 			if errors.Is(err, filesvc.ErrNotFound) {
 				status = http.StatusNotFound
@@ -363,13 +371,23 @@ func apiFiles(mux *http.ServeMux, store filesvc.MeshStore, blobs blobfs.Store, m
 		}
 
 		// 3) remote holen & cachen
+		it1, _ := store.Get(r.Context(), filesvc.ID(id))
+		peers := meshNode.PeerList()
+		ttl := 2 * time.Minute
+		if cfg := meshNode.Config(); cfg.PeerTTL > 0 {
+			ttl = cfg.PeerTTL
+		}
+		if !isOwnerActive(it1.Owner, peers, ttl) {
+			http.NotFound(w, r)
+			return
+		}
 		rrc, _, _, _, err := meshNode.FetchBlobAny(r.Context(), id)
 		if err != nil {
 			http.NotFound(w, r)
 			return
 		}
 		defer rrc.Close()
-		if _, err := blobs.Save(r.Context(), id, it.Name, rrc); err != nil {
+		if _, err := blobs.Save(r.Context(), id, it1.Name, rrc); err != nil {
 			http.Error(w, "cache failed", http.StatusInternalServerError)
 			return
 		}
@@ -381,7 +399,7 @@ func apiFiles(mux *http.ServeMux, store filesvc.MeshStore, blobs blobfs.Store, m
 			return
 		}
 		defer lrc.Close()
-		serveBlob(w, r, lrc, meta, it.Name)
+		serveBlob(w, r, lrc, meta, it1.Name)
 	})
 }
 
@@ -395,6 +413,7 @@ func toMeshSnapshot(s filesvc.Snapshot) mesh.Snapshot {
 			Name:      it.Name,
 			UpdatedAt: it.UpdatedAt,
 			Deleted:   it.Deleted,
+			Owner:     it.Owner,
 		})
 	}
 	return out
@@ -408,18 +427,45 @@ func fromMeshSnapshot(ms mesh.Snapshot) filesvc.Snapshot {
 			Name:      it.Name,
 			UpdatedAt: it.UpdatedAt,
 			Deleted:   it.Deleted,
+			Owner:     it.Owner,
 		})
 	}
 	return out
 }
 
+// isOwnerActive prüft, ob der Owner in der Peer-Liste als "aktiv" gilt.
+func isOwnerActive(owner string, peers []mesh.Peer, ttl time.Duration) bool {
+	owner = strings.TrimSpace(owner)
+	if owner == "" {
+		return true
+	}
+	cutoff := time.Now().Add(-ttl)
+	for _, p := range peers {
+		if strings.TrimSpace(p.URL) != owner {
+			continue
+		}
+		// Self ist per Definition aktiv
+		if p.Self {
+			return true
+		}
+		// ohne LastSeen: als inaktiv behandeln
+		if p.LastSeen.IsZero() {
+			return false
+		}
+		return p.LastSeen.After(cutoff)
+	}
+	// Owner ist nicht mal in der Liste: inaktiv
+	return false
+}
+
 /*** main ***/
 
 func main() {
 	cfg := loadConfig()
 
 	// Domain-Store (mesh-fähig)
-	st := filesvc.NewMemStore()
+	nodeID := strings.TrimSpace(cfg.Mesh.AdvertURL)
+	st := filesvc.NewMemStore(nodeID)
 
 	// Mesh starten
 	//mcfg := mesh.FromEnv()
@@ -463,6 +509,47 @@ func main() {
 		}
 	}()
 
+	go func() {
+		ticker := time.NewTicker(1 * time.Minute)
+		defer ticker.Stop()
+		for range ticker.C {
+			// aktive Owner bestimmen
+			peers := mnode.PeerList()
+			ttl := 2 * time.Minute
+			if cfg := mnode.Config(); cfg.PeerTTL > 0 {
+				ttl = cfg.PeerTTL
+			}
+			cutoff := time.Now().Add(-ttl)
+
+			active := map[string]bool{}
+			for _, p := range peers {
+				if p.Self {
+					active[p.URL] = true
+					continue
+				}
+				if !p.LastSeen.IsZero() && p.LastSeen.After(cutoff) {
+					active[p.URL] = true
+				}
+			}
+
+			// alle Items durchgehen; Blobs von Offline-Ownern löschen
+			var next filesvc.ID
+			for {
+				items, nextOut, _ := st.List(context.Background(), next, 1000)
+				for _, it := range items {
+					if it.Owner == "" || active[it.Owner] {
+						continue
+					}
+					_ = blobs.Delete(context.Background(), it.ID)
+				}
+				if nextOut == "" {
+					break
+				}
+				next = nextOut
+			}
+		}
+	}()
+
 	// Root-Mux
 	root := http.NewServeMux()
 
diff --git a/internal/admin/admin.go b/internal/admin/admin.go
index 25600da..54d9da1 100644
--- a/internal/admin/admin.go
+++ b/internal/admin/admin.go
@@ -60,21 +60,32 @@ func Register(mux *http.ServeMux, d Deps) {
 		items, nextOut, _ := d.Store.List(r.Context(), nextID, 100)
 
 		type row struct {
-			ID        string
-			Name      string
-			UpdatedAt int64
-			HasBlob   bool
-			Size      int64
+			ID          string
+			Name        string
+			UpdatedAt   int64
+			HasBlob     bool
+			Size        int64
+			Owner       string
+			OwnerActive bool
 		}
 		rows := make([]row, 0, len(items))
+
+		peers := d.Mesh.PeerList()
+		ttl := 2 * time.Minute
+		if cfg := d.Mesh.Config(); cfg.PeerTTL > 0 {
+			ttl = cfg.PeerTTL
+		}
+
 		for _, it := range items {
 			meta, ok, _ := d.Blob.Stat(r.Context(), it.ID)
 			rows = append(rows, row{
-				ID:        it.ID,
-				Name:      it.Name,
-				UpdatedAt: it.UpdatedAt,
-				HasBlob:   ok,
-				Size:      meta.Size,
+				ID:          it.ID,
+				Name:        it.Name,
+				UpdatedAt:   it.UpdatedAt,
+				HasBlob:     ok,
+				Size:        meta.Size,
+				Owner:       it.Owner,
+				OwnerActive: isOwnerActive(it.Owner, peers, ttl),
 			})
 		}
 
@@ -84,6 +95,42 @@ func Register(mux *http.ServeMux, d Deps) {
 		})
 	})
 
+	mux.HandleFunc("/admin/items/takeover", func(w http.ResponseWriter, r *http.Request) {
+		if r.Method != http.MethodPost {
+			http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
+			return
+		}
+		id := strings.TrimSpace(r.FormValue("id"))
+		if id != "" {
+			// Nur zulassen, wenn Owner tatsächlich offline ist
+			it, err := d.Store.Get(r.Context(), filesvc.ID(id))
+			if err == nil {
+				peers := d.Mesh.PeerList()
+				ttl := 2 * time.Minute
+				if cfg := d.Mesh.Config(); cfg.PeerTTL > 0 {
+					ttl = cfg.PeerTTL
+				}
+				if !isOwnerActive(it.Owner, peers, ttl) {
+					// eigene URL aus PeerList ermitteln
+					self := ""
+					for _, p := range peers {
+						if p.Self {
+							self = p.URL
+							break
+						}
+					}
+					if self == "" {
+						self = "unknown-self"
+					}
+					if _, err := d.Store.TakeoverOwner(r.Context(), filesvc.ID(id), self); err == nil {
+						_ = d.Mesh.SyncNow(r.Context())
+					}
+				}
+			}
+		}
+		renderItemsPartial(w, r, d)
+	})
+
 	// Upload (multipart/form-data, Feldname "file", optional name-Override)
 	mux.HandleFunc("/admin/files/upload", func(w http.ResponseWriter, r *http.Request) {
 		if r.Method != http.MethodPost {
@@ -258,25 +305,32 @@ func BasicAuth(user, pass string, next http.Handler) http.Handler {
 // rebuild & render items partial for HTMX swaps
 func renderItemsPartial(w http.ResponseWriter, r *http.Request, d Deps) {
 	type row struct {
-		ID        string
-		Name      string
-		UpdatedAt int64
-		HasBlob   bool
-		Size      int64
+		ID          string
+		Name        string
+		UpdatedAt   int64
+		HasBlob     bool
+		Size        int64
+		Owner       string
+		OwnerActive bool
 	}
 
 	nextID := filesvc.ID(strings.TrimSpace(r.URL.Query().Get("next")))
 	items, nextOut, _ := d.Store.List(r.Context(), nextID, 100)
 
+	peers := d.Mesh.PeerList()
+	ttl := 2 * time.Minute
+
 	rows := make([]row, 0, len(items))
 	for _, it := range items {
 		meta, ok, _ := d.Blob.Stat(r.Context(), (it.ID))
 		rows = append(rows, row{
-			ID:        (it.ID),
-			Name:      it.Name,
-			UpdatedAt: it.UpdatedAt,
-			HasBlob:   ok,
-			Size:      meta.Size,
+			ID:          (it.ID),
+			Name:        it.Name,
+			UpdatedAt:   it.UpdatedAt,
+			HasBlob:     ok,
+			Size:        meta.Size,
+			Owner:       it.Owner,
+			OwnerActive: isOwnerActive(it.Owner, peers, ttl),
 		})
 	}
 	w.Header().Set("Content-Type", "text/html; charset=utf-8")
@@ -285,3 +339,23 @@ func renderItemsPartial(w http.ResponseWriter, r *http.Request, d Deps) {
 		"Next":  nextOut,
 	})
 }
+
+func isOwnerActive(owner string, peers []mesh.Peer, ttl time.Duration) bool {
+	if strings.TrimSpace(owner) == "" {
+		return true
+	}
+	cutoff := time.Now().Add(-ttl)
+	for _, p := range peers {
+		if strings.TrimSpace(p.URL) == strings.TrimSpace(owner) {
+			// Self ist immer aktiv, sonst nach LastSeen
+			if p.Self {
+				return true
+			}
+			if p.LastSeen.IsZero() {
+				return false
+			}
+			return p.LastSeen.After(cutoff)
+		}
+	}
+	return false
+}
diff --git a/internal/admin/tpl/partials_items.html b/internal/admin/tpl/partials_items.html
index 5a2d8d1..3023b23 100644
--- a/internal/admin/tpl/partials_items.html
+++ b/internal/admin/tpl/partials_items.html
@@ -24,12 +24,27 @@
   <table>
     <thead>
       <tr>
-        <th>ID</th><th>Name</th><th>Updated</th><th>Blob</th><th style="width:260px">Aktionen</th>
+        <th>Owner</th><th>Status</th><th>ID</th><th>Name</th><th>Updated</th><th>Blob</th><th style="width:260px">Aktionen</th>
       </tr>
     </thead>
     <tbody>
     {{ range .Items }}
       <tr>
+        <td><small class="muted">{{ .Owner }}</small></td>
+        <td>
+        {{ if .OwnerActive }}
+            <span class="pill">online</span>
+        {{ else }}
+            <span class="pill" style="background:#5b1a1a;border-color:#7a2b2b;color:#fbb">offline</span>
+            <form style="display:inline"
+                hx-post="/admin/items/takeover"
+                hx-target="#items" hx-swap="outerHTML"
+                onsubmit="return confirm('Owner übernehmen?');">
+            <input type="hidden" name="id" value="{{ .ID }}">
+            <button class="btn" type="submit">Übernehmen</button>
+            </form>
+        {{ end }}
+        </td>
         <td>{{ .ID }}</td>
         <td>{{ .Name }}</td>
         <td><small class="muted">{{ printf "%.19s" (timeRFC3339 .UpdatedAt) }}</small></td>
diff --git a/internal/filesvc/memstore.go b/internal/filesvc/memstore.go
index 2e0d40e..4425535 100644
--- a/internal/filesvc/memstore.go
+++ b/internal/filesvc/memstore.go
@@ -11,15 +11,13 @@ import (
 type MemStore struct {
 	mu    sync.Mutex
 	items map[ID]File
-
+	self  string
 	// optionales Eventing
 	subs []chan ChangeEvent
 }
 
-func NewMemStore() *MemStore {
-	return &MemStore{
-		items: make(map[ID]File),
-	}
+func NewMemStore(self string) *MemStore {
+	return &MemStore{self: strings.TrimSpace(self), items: make(map[ID]File)}
 }
 
 /*** Store ***/
@@ -102,7 +100,7 @@ func (m *MemStore) Create(_ context.Context, name string) (File, error) {
 	if err != nil {
 		return File{}, err
 	}
-	it := File{ID: uid, Name: name, UpdatedAt: now}
+	it := File{ID: uid, Name: name, UpdatedAt: now, Owner: m.self}
 	m.items[it.ID] = it
 	m.emit(it)
 	return it, nil
@@ -120,7 +118,10 @@ func (m *MemStore) Rename(_ context.Context, id ID, newName string) (File, error
 	if !ok || it.Deleted {
 		return File{}, ErrNotFound
 	}
-	it.Name = newName
+	if it.Owner != "" && it.Owner != m.self { // ← nur Owner
+		return File{}, ErrForbidden
+	}
+	it.Name = strings.TrimSpace(newName)
 	it.UpdatedAt = time.Now().UnixNano()
 	m.items[id] = it
 	m.emit(it)
@@ -134,6 +135,9 @@ func (m *MemStore) Delete(_ context.Context, id ID) (File, error) {
 	if !ok {
 		return File{}, ErrNotFound
 	}
+	if it.Owner != "" && it.Owner != m.self { // ← nur Owner
+		return File{}, ErrForbidden
+	}
 	if it.Deleted {
 		return it, nil
 	}
@@ -144,6 +148,31 @@ func (m *MemStore) Delete(_ context.Context, id ID) (File, error) {
 	return it, nil
 }
 
+func (m *MemStore) TakeoverOwner(_ context.Context, id ID, newOwner string) (File, error) {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	it, ok := m.items[id]
+	if !ok || it.Deleted {
+		return File{}, ErrNotFound
+	}
+	newOwner = strings.TrimSpace(newOwner)
+	if newOwner == "" {
+		return File{}, ErrBadInput
+	}
+	// Sicherheit: nur für sich selbst übernehmen
+	if newOwner != m.self {
+		return File{}, ErrForbidden
+	}
+	if it.Owner == newOwner {
+		return it, nil
+	}
+	it.Owner = newOwner
+	it.UpdatedAt = time.Now().UnixNano()
+	m.items[id] = it
+	m.emitLocked(it)
+	return it, nil
+}
+
 /*** Replicable ***/
 
 func (m *MemStore) Snapshot(_ context.Context) (Snapshot, error) {
@@ -162,6 +191,10 @@ func (m *MemStore) ApplyRemote(_ context.Context, s Snapshot) error {
 	for _, ri := range s.Items {
 		li, ok := m.items[ri.ID]
 		if !ok || ri.UpdatedAt > li.UpdatedAt {
+			// Owner nie überschreiben, außer er ist leer
+			if ok && li.Owner != "" && ri.Owner != "" && ri.Owner != li.Owner {
+				ri.Owner = li.Owner
+			}
 			m.items[ri.ID] = ri
 			m.emitLocked(ri)
 		}
diff --git a/internal/filesvc/store.go b/internal/filesvc/store.go
index 6eeb5c3..d67c997 100644
--- a/internal/filesvc/store.go
+++ b/internal/filesvc/store.go
@@ -13,11 +13,11 @@ import (
 type ID = string
 
 type File struct {
-	ID   ID     `json:"id"`
-	Name string `json:"name"`
-	// weitere Metadaten optional: Size, Hash, Owner, Tags, ...
-	UpdatedAt int64 `json:"updatedAt"` // UnixNano für LWW
-	Deleted   bool  `json:"deleted"`   // Tombstone für Mesh-Delete
+	ID        ID     `json:"id"`
+	Name      string `json:"name"`
+	UpdatedAt int64  `json:"updatedAt"` // UnixNano für LWW
+	Deleted   bool   `json:"deleted"`   // Tombstone für Mesh-Delete
+	Owner     string `json:"owner"`     //AdvertURL/NodeID des Erzeugers
 }
 
 /*** Fehler ***/
@@ -36,11 +36,10 @@ type Store interface {
 	// Lesen & Auflisten
 	Get(ctx context.Context, id ID) (File, error)
 	List(ctx context.Context, next ID, limit int) (items []File, nextOut ID, err error)
-
-	// Mutationen mit LWW-Semantik (UpdatedAt wird intern gesetzt, außer bei ApplyRemote)
 	Create(ctx context.Context, name string) (File, error)
-	Rename(ctx context.Context, id ID, newName string) (File, error)
-	Delete(ctx context.Context, id ID) (File, error)
+	Rename(ctx context.Context, id ID, newName string) (File, error) // nur Owner darf
+	Delete(ctx context.Context, id ID) (File, error)                 // nur Owner darf
+	TakeoverOwner(ctx context.Context, id ID, newOwner string) (File, error)
 }
 
 /*** Mesh-Replikation ***/
diff --git a/internal/mesh/mesh.go b/internal/mesh/mesh.go
index 1b18fc7..ee28e17 100644
--- a/internal/mesh/mesh.go
+++ b/internal/mesh/mesh.go
@@ -47,6 +47,7 @@ type Item struct {
 	Name      string `json:"name"`
 	UpdatedAt int64  `json:"updatedAt"`
 	Deleted   bool   `json:"deleted"` // <— NEU: Tombstone für Deletes
+	Owner     string `json:"owner"`
 }
 
 type Snapshot struct {
@@ -92,6 +93,8 @@ func (n *Node) RemovePeer(url string) bool {
 	return false
 }
 
+func (n *Node) Config() Config { return n.cfg }
+
 // PruneNow entfernt alle Peers, deren LastSeen vor cutoff liegt (Seeds bleiben).
 func (n *Node) PruneNow(cutoff time.Time) int {
 	n.mu.Lock()