diff --git a/docs/requirements/Component-ManagementService.md b/docs/requirements/Component-ManagementService.md
index 38b1b7e7..9a6591f9 100644
--- a/docs/requirements/Component-ManagementService.md
+++ b/docs/requirements/Component-ManagementService.md
@@ -113,7 +113,7 @@ The whole folder surface is reachable from the CLI as `template folder list|crea
 
 - **AddTemplateAttribute** / **UpdateTemplateAttribute** / **DeleteTemplateAttribute**: Manage attributes on a template.
 - **AddTemplateAlarm** / **UpdateTemplateAlarm** / **DeleteTemplateAlarm**: Manage alarm definitions on a template.
-- **AddTemplateNativeAlarmSource** / **UpdateTemplateNativeAlarmSource** / **DeleteTemplateNativeAlarmSource**: Manage native alarm source bindings (the read-only OPC UA Alarms & Conditions / MxAccess Gateway mirror) on a template — `Name`, `ConnectionName`, `SourceReference`, optional `ConditionFilter` / `Description`, `IsLocked`. Mutations gated to the **Design** role; handlers write through `ITemplateEngineRepository` directly.
+- **AddTemplateNativeAlarmSource** / **UpdateTemplateNativeAlarmSource** / **DeleteTemplateNativeAlarmSource**: Manage native alarm source bindings (the read-only OPC UA Alarms & Conditions / MxAccess Gateway mirror) on a template — `Name`, `ConnectionName`, `SourceReference`, optional `ConditionFilter` / `Description`, `IsLocked`. Mutations gated to the **Design** role; handlers write through `ITemplateEngineRepository` directly — so, unlike scripts/alarms/composition slots (checked by `TemplateService`), Add/Update validate `Name` with `ActorNameRules` themselves and reject an illegal Akka actor-name element (space, `/`, leading `$`, …) with a readable error, because the name becomes part of the site actor name `native-alarm-{canonical}` (review 2026-10-21, follow-up to 01/SR-C1).
 - **ListTemplateNativeAlarmSources** (`TemplateId`): List a template's native alarm source bindings (read-only; any authenticated user).
 - **AddTemplateScript** / **UpdateTemplateScript** / **DeleteTemplateScript**: Manage scripts on a template.
 - **AddTemplateComposition** / **DeleteTemplateComposition**: Manage feature module compositions on a template.
diff --git a/src/ZB.MOM.WW.ScadaBridge.ManagementService/ManagementActor.cs b/src/ZB.MOM.WW.ScadaBridge.ManagementService/ManagementActor.cs
index 1ea6c920..81f133db 100644
--- a/src/ZB.MOM.WW.ScadaBridge.ManagementService/ManagementActor.cs
+++ b/src/ZB.MOM.WW.ScadaBridge.ManagementService/ManagementActor.cs
@@ -3309,8 +3309,23 @@ public class ManagementActor : ReceiveActor
 
     // ── Native alarm source bindings (read-only mirror; repository-direct CRUD) ──
 
+    /// <summary>
+    /// A native alarm source's name becomes part of the site actor name
+    /// <c>native-alarm-{canonical}</c>; an illegal character makes the Instance Actor's
+    /// <c>ActorOf</c> throw at deploy. Scripts, alarms and composition slots are checked by
+    /// <c>TemplateService</c>, but native-source CRUD is repository-direct here, so it applies
+    /// <see cref="ActorNameRules"/> itself (review 2026-10-21, lane F follow-up to 01/SR-C1).
+    /// </summary>
+    private static void ValidateNativeAlarmSourceName(string? name)
+    {
+        var error = ActorNameRules.Describe(name);
+        if (error is not null)
+            throw new ManagementCommandException($"Native alarm source name is invalid: {error}");
+    }
+
     private static async Task<object?> HandleAddNativeAlarmSource(IServiceProvider sp, AddTemplateNativeAlarmSourceCommand cmd, string user)
     {
+        ValidateNativeAlarmSourceName(cmd.Name);
         var repo = sp.GetRequiredService<ITemplateEngineRepository>();
         var source = new TemplateNativeAlarmSource(cmd.Name)
         {
@@ -3331,6 +3346,7 @@ public class ManagementActor : ReceiveActor
 
     private static async Task<object?> HandleUpdateNativeAlarmSource(IServiceProvider sp, UpdateTemplateNativeAlarmSourceCommand cmd, string user)
     {
+        ValidateNativeAlarmSourceName(cmd.Name);
         var repo = sp.GetRequiredService<ITemplateEngineRepository>();
         var source = await repo.GetTemplateNativeAlarmSourceByIdAsync(cmd.NativeAlarmSourceId)
             ?? throw new ManagementCommandException($"Native alarm source {cmd.NativeAlarmSourceId} not found.");
diff --git a/tests/ZB.MOM.WW.ScadaBridge.ManagementService.Tests/NativeAlarmSourceNameValidationTests.cs b/tests/ZB.MOM.WW.ScadaBridge.ManagementService.Tests/NativeAlarmSourceNameValidationTests.cs
new file mode 100644
index 00000000..c4ebfcf3
--- /dev/null
+++ b/tests/ZB.MOM.WW.ScadaBridge.ManagementService.Tests/NativeAlarmSourceNameValidationTests.cs
@@ -0,0 +1,63 @@
+using Akka.Actor;
+using Akka.TestKit.Xunit2;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Logging.Abstractions;
+using NSubstitute;
+using ZB.MOM.WW.ScadaBridge.Commons.Entities.Templates;
+using ZB.MOM.WW.ScadaBridge.Commons.Interfaces.Repositories;
+using ZB.MOM.WW.ScadaBridge.Commons.Messages.Management;
+
+namespace ZB.MOM.WW.ScadaBridge.ManagementService.Tests;
+
+/// <summary>
+/// Review 2026-10-21 (lane F follow-up to 01/SR-C1): a native alarm source's name becomes
+/// part of the site actor name <c>native-alarm-{canonical}</c>. Template scripts, alarms and
+/// composition slots are validated by <c>TemplateService</c>, but native-source CRUD is
+/// repository-direct in the ManagementActor, so it must apply <c>ActorNameRules</c> itself.
+/// </summary>
+public class NativeAlarmSourceNameValidationTests : TestKit
+{
+    private readonly ITemplateEngineRepository _repo = Substitute.For<ITemplateEngineRepository>();
+    private readonly ServiceCollection _services = new ServiceCollection().AddTestConfigurationTransaction();
+
+    /// <summary>Initializes the harness.</summary>
+    public NativeAlarmSourceNameValidationTests()
+    {
+        _services.AddScoped(_ => _repo);
+        _repo.GetTemplateNativeAlarmSourceByIdAsync(4, Arg.Any<CancellationToken>())
+            .Returns(new TemplateNativeAlarmSource("Pressure") { Id = 4, TemplateId = 1 });
+    }
+
+    private IActorRef CreateActor() =>
+        Sys.ActorOf(Props.Create(() => new ManagementActor(
+            _services.BuildServiceProvider(), NullLogger<ManagementActor>.Instance)));
+
+    private static ManagementEnvelope Designer(object command) =>
+        new(new AuthenticatedUser("d", "D", new[] { "Designer" }, Array.Empty<string>()),
+            command, Guid.NewGuid().ToString("N"));
+
+    /// <summary>Adding a source whose name is not a legal actor name is rejected before any write.</summary>
+    [Theory]
+    [InlineData("Tank Pressure")]
+    [InlineData("$system")]
+    [InlineData("a/b")]
+    public void Add_InvalidActorName_IsRejected(string name)
+    {
+        CreateActor().Tell(Designer(new AddTemplateNativeAlarmSourceCommand(1, name, "Opc", "ns=2;s=T01", null, null, false)));
+
+        var error = ExpectMsg<ManagementError>(TimeSpan.FromSeconds(5));
+        Assert.Contains("Native alarm source name is invalid", error.Error);
+        _repo.DidNotReceive().AddTemplateNativeAlarmSourceAsync(Arg.Any<TemplateNativeAlarmSource>(), Arg.Any<CancellationToken>());
+    }
+
+    /// <summary>Renaming a source to an illegal actor name is rejected before any write.</summary>
+    [Fact]
+    public void Update_RenameToInvalidActorName_IsRejected()
+    {
+        CreateActor().Tell(Designer(new UpdateTemplateNativeAlarmSourceCommand(4, "Tank Pressure", "Opc", "ns=2;s=T01", null, null, false)));
+
+        var error = ExpectMsg<ManagementError>(TimeSpan.FromSeconds(5));
+        Assert.Contains("Native alarm source name is invalid", error.Error);
+        _repo.DidNotReceive().UpdateTemplateNativeAlarmSourceAsync(Arg.Any<TemplateNativeAlarmSource>(), Arg.Any<CancellationToken>());
+    }
+}