diff --git a/app/Http/Controllers/Admin/SalesController.php b/app/Http/Controllers/Admin/SalesController.php
index 6fdc97c..a85d1b2 100644
--- a/app/Http/Controllers/Admin/SalesController.php
+++ b/app/Http/Controllers/Admin/SalesController.php
@@ -85,6 +85,16 @@ class SalesController extends Controller
         $invoicesQuery->whereBetween('created_at', [$start, $end]);
         $dispenseQuery->whereBetween('machine_time', [$start, $end]);
 
+        // 機台權限隔離：非系統管理員只能看到「自己可存取機台」的交易。沿用 Machine 的 machine_access 全域 scope
+        // 取得可存取機台集合（與上方機台下拉清單一致），修正訂單/發票/出貨清單先前未依機台授權過濾、
+        // 導致無該機台權限的帳號仍可見其交易紀錄的資料隔離漏洞。
+        if (!auth()->user()->isSystemAdmin()) {
+            $accessibleMachineIds = Machine::pluck('id');
+            $ordersQuery->whereIn('machine_id', $accessibleMachineIds);
+            $invoicesQuery->whereIn('machine_id', $accessibleMachineIds);
+            $dispenseQuery->whereIn('machine_id', $accessibleMachineIds);
+        }
+
         // 共用過濾器：機台
         if ($machineId) {
             $ordersQuery->where('machine_id', $machineId);
diff --git a/app/Services/Transaction/TransactionService.php b/app/Services/Transaction/TransactionService.php
index 088381d..338e4af 100644
--- a/app/Services/Transaction/TransactionService.php
+++ b/app/Services/Transaction/TransactionService.php
@@ -313,6 +313,17 @@ class TransactionService
                     if ((int) $slot->stock > 0) {
                         $slot->decrement('stock');
 
+                        // 售完（庫存歸 0）即清空效期與批號，避免舊批貨效期殘留。
+                        // 場景：日後管理員只補 stock 未改 expiry_date 時，update_inventory 才不會
+                        // 把過期日一起下發、把新批貨誤鎖成「暫不販售」。與機台端「賣完清效期」對稱。
+                        // 純加法：僅在仍有殘留值時才寫，不影響既有扣庫存行為。
+                        if ($slot->stock <= 0 && ($slot->expiry_date !== null || $slot->batch_no !== null)) {
+                            $slot->update([
+                                'expiry_date' => null,
+                                'batch_no' => null,
+                            ]);
+                        }
+
                         $type = \App\Models\Machine\MachineStockMovement::TYPE_SALE;
 
                         $this->machineService->recordStockMovement(
diff --git a/tests/Feature/Admin/SalesMachineAccessTest.php b/tests/Feature/Admin/SalesMachineAccessTest.php
new file mode 100644
index 0000000..8a3a120
--- /dev/null
+++ b/tests/Feature/Admin/SalesMachineAccessTest.php
@@ -0,0 +1,100 @@
+<?php
+
+namespace Tests\Feature\Admin;
+
+use App\Models\Machine\Machine;
+use App\Models\System\Company;
+use App\Models\System\Role;
+use App\Models\System\User;
+use Spatie\Permission\Models\Permission;
+use Illuminate\Foundation\Testing\RefreshDatabase;
+use Illuminate\Support\Facades\DB;
+use Tests\TestCase;
+
+/**
+ * 銷售紀錄機台權限隔離：使用者只能看到「自己可存取機台」的交易訂單，
+ * 無該機台權限者不得看到其交易（修正先前訂單清單未依機台授權過濾的漏洞）。
+ */
+class SalesMachineAccessTest extends TestCase
+{
+    use RefreshDatabase;
+
+    private Company $company;
+    private User $main;
+    private Machine $mA;
+    private Machine $mB;
+    private int $orderA;
+    private int $orderB;
+
+    protected function setUp(): void
+    {
+        parent::setUp();
+
+        Permission::create(['name' => 'menu.sales', 'guard_name' => 'web']);
+        $this->company = Company::create(['name' => 'Co', 'code' => 'CO']);
+        $role = Role::create(['name' => 'r', 'company_id' => $this->company->id, 'is_system' => false, 'guard_name' => 'web']);
+        $role->syncPermissions(['menu.sales']);
+
+        $this->main = User::factory()->create(['company_id' => $this->company->id, 'is_admin' => true, 'level' => 0]);
+        $this->main->assignRole($role);
+
+        $this->mA = Machine::factory()->create(['company_id' => $this->company->id]);
+        $this->mB = Machine::factory()->create(['company_id' => $this->company->id]);
+
+        $this->orderA = $this->makeOrder($this->mA->id);
+        $this->orderB = $this->makeOrder($this->mB->id);
+    }
+
+    private function makeOrder(int $machineId): int
+    {
+        return DB::table('orders')->insertGetId([
+            'company_id' => $this->company->id,
+            'machine_id' => $machineId,
+            'payment_type' => 1,
+            'total_amount' => 100,
+            'pay_amount' => 100,
+            'payment_status' => 1,
+            'status' => 'completed',
+            'created_at' => now(),
+            'updated_at' => now(),
+        ]);
+    }
+
+    private function visibleOrderIds(User $user): array
+    {
+        $response = $this->actingAs($user)->get(route('admin.sales.index'));
+        $response->assertOk();
+        return collect($response->viewData('orders')->items())->pluck('id')->all();
+    }
+
+    public function test_sub_account_with_machine_access_sees_only_that_machine_orders(): void
+    {
+        $sub = User::factory()->create(['company_id' => $this->company->id, 'is_admin' => false, 'level' => 1, 'parent_id' => $this->main->id]);
+        $sub->assignRole(Role::where('company_id', $this->company->id)->first());
+        $sub->machines()->attach($this->mA->id); // 只被授權 mA
+
+        $ids = $this->visibleOrderIds($sub);
+        $this->assertContains($this->orderA, $ids);
+        $this->assertNotContains($this->orderB, $ids); // 未授權 mB → 看不到其訂單
+    }
+
+    public function test_sub_account_without_any_machine_access_sees_no_orders(): void
+    {
+        $sub = User::factory()->create(['company_id' => $this->company->id, 'is_admin' => false, 'level' => 1, 'parent_id' => $this->main->id]);
+        $sub->assignRole(Role::where('company_id', $this->company->id)->first());
+        // 不授權任何機台
+
+        $ids = $this->visibleOrderIds($sub);
+        $this->assertNotContains($this->orderA, $ids);
+        $this->assertNotContains($this->orderB, $ids);
+    }
+
+    public function test_system_admin_sees_all_orders(): void
+    {
+        $sysAdmin = User::factory()->create(['company_id' => null]);
+
+        $ids = $this->visibleOrderIds($sysAdmin);
+        $this->assertContains($this->orderA, $ids);
+        $this->assertContains($this->orderB, $ids);
+    }
+}
diff --git a/tests/Feature/Transaction/ExpiryClearOnSelloutMysqlTest.php b/tests/Feature/Transaction/ExpiryClearOnSelloutMysqlTest.php
new file mode 100644
index 0000000..1bfe5dd
--- /dev/null
+++ b/tests/Feature/Transaction/ExpiryClearOnSelloutMysqlTest.php
@@ -0,0 +1,101 @@
+<?php
+
+namespace Tests\Feature\Transaction;
+
+use App\Models\Machine\Machine;
+use App\Models\System\Company;
+use App\Services\Transaction\TransactionService;
+use Illuminate\Foundation\Testing\RefreshDatabase;
+use Illuminate\Support\Facades\DB;
+use Tests\TestCase;
+
+/**
+ * 售完（庫存歸 0）自動清空效期/批號 —— 需 MySQL（recordDispense 內部寫
+ * machine_stock_movements，其 type enum 為 MySQL-only DDL，sqlite :memory: 無法驗）。執行:
+ *
+ *   ./vendor/bin/sail test -c phpunit.mysql.xml --filter ExpiryClearOnSelloutMysqlTest
+ *
+ * 在預設 sqlite 套件中自動 skip,不影響主套件綠燈。
+ *
+ * 動機：機台端「賣完清效期」已做，但 B009 補貨上報不回傳 expiry，後台若殘留舊效期，
+ * 日後管理員只補 stock 未改效期 → update_inventory 把過期日下發 → 新批貨被誤鎖。
+ * 故後台扣庫存歸 0 時亦須清效期，與機台端對稱。
+ */
+class ExpiryClearOnSelloutMysqlTest extends TestCase
+{
+    use RefreshDatabase;
+
+    private Company $company;
+    private TransactionService $service;
+
+    protected function setUp(): void
+    {
+        parent::setUp();
+
+        if (DB::connection()->getDriverName() !== 'mysql') {
+            $this->markTestSkipped('需 MySQL:machine_stock_movements.type enum 為 MySQL-only DDL。');
+        }
+
+        $this->company = Company::create(['name' => 'Test Company']);
+        $this->service = app(TransactionService::class);
+    }
+
+    private function dispense(string $serial, string $slotNo): array
+    {
+        return [
+            'serial_no' => $serial,
+            'slot_no' => $slotNo,
+            'product_id' => 101,
+            'amount' => 50,
+            'dispense_status' => 1,
+        ];
+    }
+
+    /** 庫存賣到 0 → 效期與批號被清空。 */
+    public function test_clears_expiry_and_batch_when_stock_hits_zero(): void
+    {
+        $serial = '1234567890';
+        $machine = Machine::factory()->create([
+            'company_id' => $this->company->id,
+            'serial_no' => $serial,
+        ]);
+        $slot = $machine->slots()->create([
+            'slot_no' => '1',
+            'stock' => 1,
+            'max_stock' => 10,
+            'expiry_date' => '2030-12-31',
+            'batch_no' => 'B-001',
+        ]);
+
+        $this->service->recordDispense($this->dispense($serial, '1'));
+
+        $fresh = $slot->fresh();
+        $this->assertEquals(0, $fresh->stock, '庫存應扣為 0');
+        $this->assertNull($fresh->expiry_date, '售完應清空效期');
+        $this->assertNull($fresh->batch_no, '售完應清空批號');
+    }
+
+    /** 庫存尚未歸 0 → 效期與批號保留（同批貨還在販售）。 */
+    public function test_keeps_expiry_when_stock_remains(): void
+    {
+        $serial = '1234567891';
+        $machine = Machine::factory()->create([
+            'company_id' => $this->company->id,
+            'serial_no' => $serial,
+        ]);
+        $slot = $machine->slots()->create([
+            'slot_no' => '2',
+            'stock' => 5,
+            'max_stock' => 10,
+            'expiry_date' => '2030-12-31',
+            'batch_no' => 'B-001',
+        ]);
+
+        $this->service->recordDispense($this->dispense($serial, '2'));
+
+        $fresh = $slot->fresh();
+        $this->assertEquals(4, $fresh->stock, '庫存應扣為 4');
+        $this->assertEquals('2030-12-31', $fresh->expiry_date->format('Y-m-d'), '未售完應保留效期');
+        $this->assertEquals('B-001', $fresh->batch_no, '未售完應保留批號');
+    }
+}