diff --git a/cmd/mesh-host/nodeagent.go b/cmd/mesh-host/nodeagent.go
index d772d61..1af795b 100644
--- a/cmd/mesh-host/nodeagent.go
+++ b/cmd/mesh-host/nodeagent.go
@@ -601,6 +601,7 @@ func nodeAgent(ctx context.Context, opts options, signer ed25519.PublicKey, sess
 		if composer != nil {
 			composes.set(delivery.ComposesOwn)
 			env.Composed, env.SelfComposed, env.Trusted, env.Policy = composer, true, nil, composer.Policy
+			env.HoldsData = composer.HoldsData // what runs from the kept declaration says Data as its manifest does
 			session.NoteComposes(linked, delivery.ComposesOwn, why)
 			// And once the catalogue no longer places it, the agent begins again on the controller's compositions: the
 			// placement key deleted ends this run, the way back (issue 1126, the seed's revert).
diff --git a/internal/agent/agent.go b/internal/agent/agent.go
index 62df761..acb91db 100644
--- a/internal/agent/agent.go
+++ b/internal/agent/agent.go
@@ -151,6 +151,11 @@ type Env struct {
 	// move of a module of policy record that recreates a container or moves its data waits for a person's yes in its
 	// want (ADR 0547 §3). Nil judges no move.
 	Policy func(ctx context.Context, module string) string
+	// HoldsData says whether a module's manifest declares data (catalogue.Manifest.DataItems), and whether its manifest
+	// could be read: what a composition's Data is, for what runs of a module from the kept declaration, which carries no
+	// Data of its own. A composition says Data, so without it a data module from the kept declaration is judged to move
+	// its data against its first composition after a restart (mongodb and mssql on novox, issue 924). Nil reads none.
+	HoldsData func(ctx context.Context, module string) (data, known bool)
 }
 
 // transientFor is how many transient retries say the phase applying before the have says failed: past them the bus has
@@ -172,6 +177,9 @@ type Agent struct {
 	// composition, read once at the start (loadHad): what runs of a module the agent has not taken yet, ahead of the kept
 	// declaration (issue 924).
 	had map[string]compNow
+	// keptData is, for each module of the kept declaration whose manifest could be read, whether it declares data
+	// (Env.HoldsData): the Data of what runs of it from the kept declaration.
+	keptData map[string]bool
 	// attempt is the last apply of a module that failed or is held, with the revisions it was made from.
 	attempt map[string]attempt
 	checked map[string]bool
@@ -230,7 +238,7 @@ func New(env Env) *Agent {
 	if env.Say == nil {
 		env.Say = func(string) {}
 	}
-	return &Agent{env: env, wants: map[string]wantNow{}, comps: map[string]compNow{}, running: map[string]delivery.Have{}, applied: map[string]compNow{}, had: map[string]compNow{},
+	return &Agent{env: env, wants: map[string]wantNow{}, comps: map[string]compNow{}, running: map[string]delivery.Have{}, applied: map[string]compNow{}, had: map[string]compNow{}, keptData: map[string]bool{},
 		attempt: map[string]attempt{}, checked: map[string]bool{}, prior: map[string]bool{}, said: map[string]string{}, notComposed: map[string]notComposedMark{},
 		retry: make(chan []string, 8), reconcile: make(chan []string, 64), tries: map[string]int{}, again: make(chan againAsk, 64),
 		transient: make(chan struct{}, 1), stopped: make(chan struct{})}
@@ -808,10 +816,7 @@ func (a *Agent) others(except string) []delivery.Composed {
 		}
 		sort.Strings(names)
 		for _, m := range names {
-			c := delivery.Composed{Node: a.env.Node, Module: m, Resources: kept[m]}
-			if a.env.KeptFilled != nil {
-				c.Filled = a.env.KeptFilled()[m]
-			}
+			c, _ := a.keptComposed(m, kept[m])
 			if m == NodeModule {
 				c.Module = ""
 			}
@@ -846,12 +851,13 @@ func (a *Agent) loadHad(ctx context.Context) {
 		names = append(names, m)
 	}
 	sort.Strings(names)
+	a.readKeptData(ctx, names...)
 	for _, m := range names {
 		if ctx.Err() != nil {
 			return
 		}
 		h, ok := a.env.Haves.Read(ctx, m)
-		if !ok || h.Composed == "" || h.Phase == string(delivery.PhaseRemoved) {
+		if !ok || h.Composed == "" || !haveRuns(h) {
 			continue
 		}
 		a.mu.Lock()
@@ -871,6 +877,17 @@ func (a *Agent) loadHad(ctx context.Context) {
 	}
 }
 
+// haveRuns says a have names what runs, in the phases baseline takes as running: running (or empty), held for a failed
+// backup, or a composer's mark over what still runs. A have backing up, applying, checking, failed or waiting names a
+// composition not applied, or not yet (issue 924, review of 031e106).
+func haveRuns(h Have) bool {
+	switch delivery.Phase(h.Phase) {
+	case "", delivery.PhaseRunning, delivery.PhaseHeld:
+		return true
+	}
+	return composerMark(h)
+}
+
 // keptHas says whether the kept declaration has resources for the module. Called holding a.mu or not: Kept takes no lock
 // of the agent's.
 func (a *Agent) keptHas(module string) ([]json.RawMessage, bool) {
@@ -1009,7 +1026,8 @@ func (a *Agent) heldOut(except string) []delivery.Composed {
 			}
 		}
 		if len(rs) > 0 {
-			out = append(out, delivery.Composed{Node: a.env.Node, Module: m, Resources: rs})
+			// Held out, never judged: its Data from its manifest where known, as every other composition says it.
+			out = append(out, delivery.Composed{Node: a.env.Node, Module: m, Resources: rs, Data: a.keptData[m]})
 		}
 	}
 	return out
@@ -1397,6 +1415,7 @@ func (a *Agent) waitsForYes(ctx context.Context, module string, w wantNow, comp
 	if module == NodeModule || a.env.Policy == nil || a.env.Policy(ctx, module) != catalogue.PolicyRecord || w.Want.Yes == comp.Dig {
 		return false
 	}
+	a.readKeptData(ctx, module) // the manifest may read now though it did not at the start
 	a.mu.Lock()
 	r, ran := a.running[module]
 	if ran && r.Composed == comp.Dig && r.Phase != delivery.PhaseRemoved {
@@ -1442,14 +1461,61 @@ func (a *Agent) waitsForYes(ctx context.Context, module string, w wantNow, comp
 
 // runningComposition is what the module runs now: the composition last applied, else its resources in the declaration
 // the node kept from before the switch. Called with a.mu held.
+//
+// The composition its have named at the start comes before the kept declaration (issue 924). From the kept declaration,
+// what runs carries Data as its manifest declares it; a module whose manifest could not be read cannot be judged against
+// it (false), and that is said, rather than taking it to hold no data and judging a false move of its data.
 func (a *Agent) runningComposition(module string) (delivery.Composed, bool) {
 	if c, ok := a.applied[module]; ok && c.Err == nil {
 		return c.C, true
 	}
-	if a.env.Kept != nil {
-		if rs, ok := a.env.Kept()[module]; ok {
-			return delivery.Composed{Node: a.env.Node, Module: module, Resources: rs}, true
+	if c, ok := a.had[module]; ok {
+		return c.C, true
+	}
+	if rs, ok := a.keptHas(module); ok {
+		c, known := a.keptComposed(module, rs)
+		if !known {
+			a.sayOnce("kept-data:"+module, fmt.Sprintf("%s runs from the kept declaration, and whether it holds data cannot be "+
+				"read from its manifest: a move of it cannot be judged", module))
 		}
+		return c, known
 	}
 	return delivery.Composed{}, false
 }
+
+// keptComposed is what runs of a module from the kept declaration: its resources there, the paths it names as filled,
+// and Data as the module's manifest declares it; false when the manifest could not be read, so Data is not known. Called
+// with a.mu held.
+func (a *Agent) keptComposed(module string, rs []json.RawMessage) (delivery.Composed, bool) {
+	c := delivery.Composed{Node: a.env.Node, Module: module, Resources: rs}
+	if a.env.KeptFilled != nil {
+		c.Filled = a.env.KeptFilled()[module]
+	}
+	data, known := a.keptData[module]
+	c.Data = data
+	return c, known || module == NodeModule
+}
+
+// readKeptData reads, outside the agent's lock, whether each module of the kept declaration not known yet declares data
+// (Env.HoldsData), and keeps the answers it could read.
+func (a *Agent) readKeptData(ctx context.Context, modules ...string) {
+	if a.env.HoldsData == nil {
+		return
+	}
+	for _, m := range modules {
+		if m == NodeModule {
+			continue
+		}
+		a.mu.Lock()
+		_, done := a.keptData[m]
+		a.mu.Unlock()
+		if _, kept := a.keptHas(m); done || !kept {
+			continue
+		}
+		if data, known := a.env.HoldsData(ctx, m); known {
+			a.mu.Lock()
+			a.keptData[m] = data
+			a.mu.Unlock()
+		}
+	}
+}
diff --git a/internal/agent/agent_test.go b/internal/agent/agent_test.go
index f3c0b7e..a73faa2 100644
--- a/internal/agent/agent_test.go
+++ b/internal/agent/agent_test.go
@@ -1031,6 +1031,9 @@ func TestTheRevisionAWantNamesIsAppliedFromHistory(t *testing.T) {
 // for claude-code and screen-lock, 2026-10-25); from the composition its have names once it has one, the kept
 // declaration being older, read at the start before any module settles and told to the filling then, so a file the
 // newer composition fills is accepted on the first fill (power's three drop-ins on ace, g14 and shanks, 2026-10-29).
+// Only a have in a phase baseline takes as running names what runs; and what runs carries Data, from the composition
+// or, from the kept declaration, from the module's manifest, so a data module is not judged to move its data against
+// its first composition after a restart (mongodb and mssql on novox).
 func TestWhatRunsBeforeTheAgentTakesAModuleNamesItsFilledPaths(t *testing.T) {
 	const old, added = "/tmp/r6/power/settings", "/tmp/r6/power/bound"
 	filledFile := func(id string) json.RawMessage {
@@ -1039,7 +1042,7 @@ func TestWhatRunsBeforeTheAgentTakesAModuleNamesItsFilledPaths(t *testing.T) {
 	}
 	fp := fpOf("a")
 	ck, _ := delivery.ComposedKey(node, "power", fp)
-	applied := delivery.Composed{Node: node, Module: "power", FP: fp, Filled: []string{old, added},
+	applied := delivery.Composed{Node: node, Module: "power", FP: fp, Filled: []string{old, added}, Data: true,
 		Resources: []json.RawMessage{filledFile("settings"), filledFile("bound")}}
 	_, appliedRaw, appliedDig := signedBy(t, applied, ck, controllerKey)
 	newer := applied
@@ -1053,13 +1056,21 @@ func TestWhatRunsBeforeTheAgentTakesAModuleNamesItsFilledPaths(t *testing.T) {
 		bucket       []byte
 		history      []Update
 		filled, told string
+		// data is what runs' Data; holdsData the manifest's answer (nil: none read).
+		data      bool
+		holdsData func(context.Context, string) (bool, bool)
 	}{
 		{name: "no have: the kept declaration's", filled: old},
 		{name: "a have naming the bucket's value", have: &Have{Module: "power", FP: fp, Composed: appliedDig},
-			bucket: appliedRaw, filled: old + "," + added, told: "the haves were read at the start"},
+			bucket: appliedRaw, filled: old + "," + added, told: "the haves were read at the start", data: true},
+		{name: "a have applying names nothing that runs yet", have: &Have{Module: "power", FP: fp, Composed: appliedDig,
+			Phase: string(delivery.PhaseApplying)}, bucket: appliedRaw, filled: old, told: "the haves were read at the start"},
+		{name: "a data module from the kept declaration says Data as its manifest does", filled: old,
+			told: "the haves were read at the start", data: true,
+			holdsData: func(context.Context, string) (bool, bool) { return true, true }},
 		{name: "a have naming a revision replaced since", have: &Have{Module: "power", FP: fp, Composed: appliedDig},
 			bucket: newerRaw, history: []Update{{Key: ck, Value: appliedRaw, Revision: 3}, {Key: ck, Value: newerRaw, Revision: 7}},
-			filled: old + "," + added, told: "the haves were read at the start"},
+			filled: old + "," + added, told: "the haves were read at the start", data: true},
 		{name: "a have naming a composition the bucket no longer keeps", have: &Have{Module: "power", FP: fp, Composed: appliedDig},
 			bucket: newerRaw, filled: old, told: "the haves were read at the start"},
 	} {
@@ -1074,12 +1085,16 @@ func TestWhatRunsBeforeTheAgentTakesAModuleNamesItsFilledPaths(t *testing.T) {
 				b.comps.before(ck, tc.bucket)
 			}
 			b.env.Revisions = func(_ context.Context, key string) ([]Update, error) { return tc.history, nil }
+			b.env.HoldsData = tc.holdsData
 			var told []string
 			var mu sync.Mutex
 			b.env.RunsChanged = func(why string) { mu.Lock(); told = append(told, why); mu.Unlock() }
 			filledNow := func() string {
 				for _, c := range b.ag.Everything() {
 					if c.Module == "power" {
+						if c.Data != tc.data {
+							t.Errorf("what runs says Data %v, want %v", c.Data, tc.data)
+						}
 						return strings.Join(c.Filled, ",")
 					}
 				}
diff --git a/internal/selfcompose/selfcompose.go b/internal/selfcompose/selfcompose.go
index fb14265..b8bee19 100644
--- a/internal/selfcompose/selfcompose.go
+++ b/internal/selfcompose/selfcompose.go
@@ -743,6 +743,27 @@ func (c *Composer) Policy(ctx context.Context, module string) string {
 	return policy
 }
 
+// HoldsData says whether a module's manifest declares data (catalogue.Manifest.DataItems), as a composition's Data says
+// it, and whether the manifest could be read: the agent's Data for what runs of a module from the kept declaration
+// (agent.Env.HoldsData, issue 924).
+func (c *Composer) HoldsData(ctx context.Context, module string) (data, known bool) {
+	c.mu.Lock()
+	m, ok := c.modules[module]
+	c.mu.Unlock()
+	if !ok || m.Manifest == "" {
+		return false, false
+	}
+	raw, err := reader{c: c}.Manifest(ctx, m.Manifest)
+	if err != nil {
+		return false, false
+	}
+	parsed, err := catalogue.ParseManifestForInputs(raw)
+	if err != nil {
+		return false, false
+	}
+	return len(parsed.DataItems()) > 0, true
+}
+
 // reader is the composer's view of the bus as frombus reads it.
 type reader struct{ c *Composer }