diff --git a/src/api/SIGCM2.Application/Rubros/Move/MoveRubroCommandHandler.cs b/src/api/SIGCM2.Application/Rubros/Move/MoveRubroCommandHandler.cs
index 8bd32f5..8adeda7 100644
--- a/src/api/SIGCM2.Application/Rubros/Move/MoveRubroCommandHandler.cs
+++ b/src/api/SIGCM2.Application/Rubros/Move/MoveRubroCommandHandler.cs
@@ -13,17 +13,20 @@ public sealed class MoveRubroCommandHandler : ICommandHandler<MoveRubroCommand,
     private readonly IAuditLogger _audit;
     private readonly TimeProvider _timeProvider;
     private readonly RubrosOptions _options;
+    private readonly IAvisoQueryRepository _avisoQuery;
 
     public MoveRubroCommandHandler(
         IRubroRepository repo,
         IAuditLogger audit,
         TimeProvider timeProvider,
-        IOptions<RubrosOptions> options)
+        IOptions<RubrosOptions> options,
+        IAvisoQueryRepository avisoQuery)
     {
         _repo = repo;
         _audit = audit;
         _timeProvider = timeProvider;
         _options = options.Value;
+        _avisoQuery = avisoQuery;
     }
 
     public async Task<RubroMovedDto> Handle(MoveRubroCommand command)
@@ -47,6 +50,12 @@ public sealed class MoveRubroCommandHandler : ICommandHandler<MoveRubroCommand,
             if (!newParent.Activo)
                 throw new RubroPadreInactivoException(command.NuevoParentId.Value);
 
+            // CAT-002: Regla de Oro — nuevo padre no puede ser hoja con avisos
+            // CAT-002/PRD-002 TOCTOU — evaluar upgrade a RepeatableRead o constraint DB cuando exista dbo.Aviso
+            var avisosCount = await _avisoQuery.CountAvisosEnRubroAsync(command.NuevoParentId.Value);
+            if (avisosCount > 0)
+                throw new RubroPadreEsHojaConAvisosException(command.NuevoParentId.Value, avisosCount);
+
             // Depth check
             var parentDepth = await _repo.GetDepthAsync(command.NuevoParentId);
             var newDepth = parentDepth + 1;
diff --git a/tests/SIGCM2.Application.Tests/Rubros/Move/MoveRubroCommandHandlerTests.cs b/tests/SIGCM2.Application.Tests/Rubros/Move/MoveRubroCommandHandlerTests.cs
index 51bea63..9f4046c 100644
--- a/tests/SIGCM2.Application.Tests/Rubros/Move/MoveRubroCommandHandlerTests.cs
+++ b/tests/SIGCM2.Application.Tests/Rubros/Move/MoveRubroCommandHandlerTests.cs
@@ -17,6 +17,7 @@ public class MoveRubroCommandHandlerTests
     private readonly IAuditLogger _audit = Substitute.For<IAuditLogger>();
     private readonly FakeTimeProvider _timeProvider = new(new DateTimeOffset(2026, 4, 18, 12, 0, 0, TimeSpan.Zero));
     private readonly IOptions<RubrosOptions> _options = Options.Create(new RubrosOptions { MaxDepth = 10 });
+    private readonly IAvisoQueryRepository _avisoQuery = Substitute.For<IAvisoQueryRepository>();
     private readonly MoveRubroCommandHandler _handler;
 
     private static Rubro MakeRubro(int id, int? parentId = null, bool activo = true)
@@ -32,8 +33,11 @@ public class MoveRubroCommandHandlerTests
              .Returns(0);
         _repo.GetMaxOrdenAsync(Arg.Any<int?>(), Arg.Any<CancellationToken>())
              .Returns(0);
+        // Default: no avisos
+        _avisoQuery.CountAvisosEnRubroAsync(Arg.Any<int>(), Arg.Any<CancellationToken>())
+                   .Returns(0);
 
-        _handler = new MoveRubroCommandHandler(_repo, _audit, _timeProvider, _options);
+        _handler = new MoveRubroCommandHandler(_repo, _audit, _timeProvider, _options, _avisoQuery);
     }
 
     // ── Happy path: move to other parent ────────────────────────────────────
@@ -173,4 +177,66 @@ public class MoveRubroCommandHandlerTests
 
         await act.Should().ThrowAsync<RubroMaxDepthExceededException>();
     }
+
+    // ── CAT-002: Guard nuevo padre sin avisos ───────────────────────────────
+
+    [Fact]
+    public async Task Handle_NuevoParentTieneAvisos_Throws_RubroPadreEsHojaConAvisosException()
+    {
+        const int nuevoParentId = 20;
+        var rubro = MakeRubro(8, parentId: 2);
+        var newParent = MakeRubro(nuevoParentId);
+        _repo.GetByIdAsync(8, Arg.Any<CancellationToken>()).Returns(rubro);
+        _repo.GetByIdAsync(nuevoParentId, Arg.Any<CancellationToken>()).Returns(newParent);
+        _avisoQuery.CountAvisosEnRubroAsync(nuevoParentId, Arg.Any<CancellationToken>()).Returns(2);
+
+        var act = () => _handler.Handle(new MoveRubroCommand(Id: 8, NuevoParentId: nuevoParentId, NuevoOrden: 0));
+
+        await act.Should().ThrowAsync<RubroPadreEsHojaConAvisosException>()
+            .Where(ex => ex.ParentId == nuevoParentId && ex.CantidadAvisos == 2);
+    }
+
+    [Fact]
+    public async Task Handle_NuevoParentTieneCeroAvisos_DoesNotThrow()
+    {
+        const int nuevoParentId = 20;
+        var rubro = MakeRubro(8, parentId: 2);
+        var newParent = MakeRubro(nuevoParentId);
+        _repo.GetByIdAsync(8, Arg.Any<CancellationToken>()).Returns(rubro);
+        _repo.GetByIdAsync(nuevoParentId, Arg.Any<CancellationToken>()).Returns(newParent);
+        _avisoQuery.CountAvisosEnRubroAsync(nuevoParentId, Arg.Any<CancellationToken>()).Returns(0);
+
+        var result = await _handler.Handle(new MoveRubroCommand(Id: 8, NuevoParentId: nuevoParentId, NuevoOrden: 0));
+
+        result.Id.Should().Be(8);
+    }
+
+    [Fact]
+    public async Task Handle_NuevoParentEsNull_SkipsAvisosGuard()
+    {
+        // Move to root — no parent to check avisos for
+        var rubro = MakeRubro(8, parentId: 2);
+        _repo.GetByIdAsync(8, Arg.Any<CancellationToken>()).Returns(rubro);
+
+        await _handler.Handle(new MoveRubroCommand(Id: 8, NuevoParentId: null, NuevoOrden: 0));
+
+        await _avisoQuery.DidNotReceive().CountAvisosEnRubroAsync(Arg.Any<int>(), Arg.Any<CancellationToken>());
+    }
+
+    [Fact]
+    public async Task Handle_CycleCheck_Wins_OverAvisosGuard()
+    {
+        // Cycle check fires before avisos guard
+        const int nuevoParentId = 10;
+        var rubro = MakeRubro(5, parentId: null);
+        _repo.GetByIdAsync(5, Arg.Any<CancellationToken>()).Returns(rubro);
+        // nuevoParentId IS a descendant (cycle)
+        _repo.GetDescendantsAsync(5, Arg.Any<CancellationToken>())
+             .Returns(new[] { MakeRubro(nuevoParentId, parentId: 5) });
+        _avisoQuery.CountAvisosEnRubroAsync(nuevoParentId, Arg.Any<CancellationToken>()).Returns(3);
+
+        var act = () => _handler.Handle(new MoveRubroCommand(Id: 5, NuevoParentId: nuevoParentId, NuevoOrden: 0));
+
+        await act.Should().ThrowAsync<RubroCycleDetectedException>();
+    }
 }