diff --git a/packages/warehouse-core/src/inventory/stock-movement-actor.test.ts b/packages/warehouse-core/src/inventory/stock-movement-actor.test.ts
new file mode 100644
index 00000000..f4ed6ad8
--- /dev/null
+++ b/packages/warehouse-core/src/inventory/stock-movement-actor.test.ts
@@ -0,0 +1,34 @@
+import { test } from 'node:test';
+import assert from 'node:assert/strict';
+import { StockMovement } from './stock-movement.js';
+import { StockMovementId } from './stock-movement-id.js';
+import { StockItemId } from './stock-item-id.js';
+import { Quantity } from './quantity.js';
+import { MovementKind } from './movement-enums.js';
+import { ScopeId } from '../kernel/index.js';
+
+const BASE = {
+  id: StockMovementId.fromString('11111111-1111-4111-8111-111111111111'),
+  scopeId: ScopeId.fromString('22222222-2222-4222-8222-222222222222'),
+  kind: MovementKind.Receipt,
+  quantity: Quantity.of(5, 'und'),
+  toItemId: StockItemId.fromString('33333333-3333-4333-8333-333333333333'),
+  occurredAt: new Date('2026-07-14T10:00:00.000Z'),
+};
+
+test('actorId por defecto null (movimiento sin autor conocido)', () => {
+  const m = StockMovement.record(BASE);
+  assert.equal(m.actorId, null);
+});
+
+test('actorId opaco se conserva y hace round-trip por snapshot', () => {
+  const m = StockMovement.record({ ...BASE, actorId: 'user-42' });
+  assert.equal(m.actorId, 'user-42');
+  const back = StockMovement.fromSnapshot(m.toSnapshot());
+  assert.equal(back.actorId, 'user-42');
+});
+
+test('actorId vacío se normaliza a null', () => {
+  const m = StockMovement.record({ ...BASE, actorId: '   ' });
+  assert.equal(m.actorId, null);
+});
diff --git a/packages/warehouse-core/src/inventory/stock-movement.ts b/packages/warehouse-core/src/inventory/stock-movement.ts
index 88f74091..a1b7896d 100644
--- a/packages/warehouse-core/src/inventory/stock-movement.ts
+++ b/packages/warehouse-core/src/inventory/stock-movement.ts
@@ -23,6 +23,12 @@ export interface RecordStockMovementProps {
    * movement by key before applying, guarding against double entradas.
    */
   idempotencyKey?: string | null;
+  /**
+   * Quién ejecutó el movimiento (cadena de custodia). Id opaco: el paquete no
+   * resuelve identidad ni permisos — eso lo hace el host (#355). Null = sin
+   * autor conocido (movimientos históricos o del sistema).
+   */
+  actorId?: string | null;
   occurredAt?: Date;
 }
 
@@ -36,6 +42,7 @@ export interface StockMovementSnapshot {
   toItemId: string | null;
   reason: string | null;
   idempotencyKey: string | null;
+  actorId: string | null;
   occurredAt: Date;
 }
 
@@ -73,6 +80,7 @@ export class StockMovement {
     public readonly toItemId: StockItemId | null,
     public readonly reason: string | null,
     public readonly idempotencyKey: string | null,
+    public readonly actorId: string | null,
     public readonly occurredAt: Date,
   ) {}
 
@@ -95,6 +103,7 @@ export class StockMovement {
       to,
       normalizeText(props.reason),
       normalizeText(props.idempotencyKey),
+      normalizeText(props.actorId),
       props.occurredAt ?? new Date(),
     );
   }
@@ -109,6 +118,7 @@ export class StockMovement {
       s.toItemId !== null ? StockItemId.fromString(s.toItemId) : null,
       s.reason,
       s.idempotencyKey,
+      s.actorId,
       s.occurredAt,
     );
   }
@@ -134,6 +144,7 @@ export class StockMovement {
       toItemId: this.toItemId?.value ?? null,
       reason: this.reason,
       idempotencyKey: this.idempotencyKey,
+      actorId: this.actorId,
       occurredAt: this.occurredAt,
     };
   }
diff --git a/packages/warehouse-postgres/migrations/wms_0004_movement_actor.sql b/packages/warehouse-postgres/migrations/wms_0004_movement_actor.sql
new file mode 100644
index 00000000..9dd17d9c
--- /dev/null
+++ b/packages/warehouse-postgres/migrations/wms_0004_movement_actor.sql
@@ -0,0 +1,13 @@
+-- wms_0004_movement_actor — cadena de custodia del kardex (Inc 3 del EPIC de
+-- flota). Añade a `wms.stock_movements` el autor del asiento (`actor_id`): un id
+-- OPACO (el paquete no resuelve identidad ni permisos — eso lo hace el host,
+-- #355). Nullable: los asientos históricos quedan sin autor.
+--
+-- Aditiva: el libro mayor sigue siendo inmutable (sólo INSERT); esto sólo suma
+-- una columna que se rellena en el alta. Idempotente.
+--
+-- Migración inmutable una vez fusionada: corregir hacia adelante con un nuevo
+-- `wms_*.sql`, nunca editar este fichero.
+
+ALTER TABLE wms.stock_movements
+  ADD COLUMN IF NOT EXISTS actor_id text;
diff --git a/packages/warehouse-postgres/src/inventory/drizzle-stock-movement.repository.test.ts b/packages/warehouse-postgres/src/inventory/drizzle-stock-movement.repository.test.ts
index 370c8240..6fc600ed 100644
--- a/packages/warehouse-postgres/src/inventory/drizzle-stock-movement.repository.test.ts
+++ b/packages/warehouse-postgres/src/inventory/drizzle-stock-movement.repository.test.ts
@@ -39,6 +39,7 @@ describe('DrizzleStockMovementRepository (integración)', () => {
     toItemId: StockItemId;
     amount?: number;
     idempotencyKey?: string | null;
+    actorId?: string | null;
   }): StockMovement {
     return StockMovement.record({
       id: StockMovementId.create(),
@@ -48,6 +49,7 @@ describe('DrizzleStockMovementRepository (integración)', () => {
       toItemId: opts.toItemId,
       reason: 'Entrada de donación',
       idempotencyKey: opts.idempotencyKey ?? null,
+      actorId: opts.actorId ?? null,
     });
   }
 
@@ -61,6 +63,20 @@ describe('DrizzleStockMovementRepository (integración)', () => {
     assert.deepEqual(loaded.toSnapshot(), movement.toSnapshot());
   });
 
+  it('actorId (cadena de custodia) hace round-trip', async () => {
+    const scopeId = ScopeId.create();
+    const movement = receipt({
+      scopeId,
+      toItemId: StockItemId.create(),
+      actorId: 'coordinador-7',
+    });
+    await repo.append(movement);
+
+    const loaded = await repo.findById(movement.id);
+    assert.ok(loaded);
+    assert.equal(loaded.actorId, 'coordinador-7');
+  });
+
   it('idempotencia: la misma clave insertada dos veces deja una sola fila', async () => {
     const scopeId = ScopeId.create();
     const toItemId = StockItemId.create();
diff --git a/packages/warehouse-postgres/src/inventory/mappers.ts b/packages/warehouse-postgres/src/inventory/mappers.ts
index 0284cca9..81671c41 100644
--- a/packages/warehouse-postgres/src/inventory/mappers.ts
+++ b/packages/warehouse-postgres/src/inventory/mappers.ts
@@ -234,6 +234,7 @@ export function rowToStockMovementSnapshot(
     toItemId: row.toItemId ?? null,
     reason: row.reason ?? null,
     idempotencyKey: row.idempotencyKey ?? null,
+    actorId: row.actorId ?? null,
     occurredAt: row.occurredAt,
   };
 }
@@ -251,6 +252,7 @@ export function stockMovementSnapshotToRow(
     toItemId: s.toItemId,
     reason: s.reason,
     idempotencyKey: s.idempotencyKey,
+    actorId: s.actorId,
     occurredAt: s.occurredAt,
   };
 }
diff --git a/packages/warehouse-postgres/src/inventory/schema.ts b/packages/warehouse-postgres/src/inventory/schema.ts
index ded4a2ff..12085c2a 100644
--- a/packages/warehouse-postgres/src/inventory/schema.ts
+++ b/packages/warehouse-postgres/src/inventory/schema.ts
@@ -110,6 +110,7 @@ export const stockMovementsTable = wms.table('stock_movements', {
   toItemId: uuid('to_item_id'),
   reason: text('reason'),
   idempotencyKey: text('idempotency_key'),
+  actorId: text('actor_id'),
   occurredAt: timestamp('occurred_at', { withTimezone: true }).notNull(),
 });