diff --git a/archreview/plans/R2-11-tagconfig-consolidation-plan.md.tasks.json b/archreview/plans/R2-11-tagconfig-consolidation-plan.md.tasks.json
index 51fa593f..9baa9f94 100644
--- a/archreview/plans/R2-11-tagconfig-consolidation-plan.md.tasks.json
+++ b/archreview/plans/R2-11-tagconfig-consolidation-plan.md.tasks.json
@@ -19,7 +19,7 @@
     { "id": "T15", "subject": "AbLegacy equipment-tag parser: freeze test, shared readers, honour writable key, Inspect warnings", "status": "completed", "blockedBy": ["T11"] },
     { "id": "T16", "subject": "TwinCAT equipment-tag parser: freeze test, shared readers, honour writable key, Inspect warnings", "status": "completed", "blockedBy": ["T11"] },
     { "id": "T17", "subject": "FOCAS equipment-tag parser: force Writable:false (05/UNDER-1 correction), shared readers, Inspect warnings (+ amend Contracts banner)", "status": "completed", "blockedBy": ["T11"] },
-    { "id": "T18", "subject": "FOCAS capability-matrix pre-flight on the equipment-tag _parseRef resolve path (BadNodeIdUnknown on rejection)", "status": "pending", "blockedBy": ["T17"] },
+    { "id": "T18", "subject": "FOCAS capability-matrix pre-flight on the equipment-tag _parseRef resolve path (BadNodeIdUnknown on rejection)", "status": "completed", "blockedBy": ["T17"] },
     { "id": "T19", "subject": "Modbus probe parses the factory DTO shape (timeoutMs round-trip; OpcUaClient parity rule)", "status": "pending", "blockedBy": [] },
     { "id": "T20", "subject": "EquipmentTagConfigInspector DriverType-dispatch map in ControlPlane (+6 Contracts references)", "status": "pending", "blockedBy": ["T12", "T13", "T14", "T15", "T16", "T17"] },
     { "id": "T21", "subject": "AdminOperationsActor deploy-gate wiring + Deployment:TagConfigValidationMode (Warn default | Error opt-in); actor-level consuming test", "status": "pending", "blockedBy": ["T20"] },
diff --git a/src/Drivers/ZB.MOM.WW.OtOpcUa.Driver.FOCAS/FocasDriver.cs b/src/Drivers/ZB.MOM.WW.OtOpcUa.Driver.FOCAS/FocasDriver.cs
index d36d6f0b..d2ba8789 100644
--- a/src/Drivers/ZB.MOM.WW.OtOpcUa.Driver.FOCAS/FocasDriver.cs
+++ b/src/Drivers/ZB.MOM.WW.OtOpcUa.Driver.FOCAS/FocasDriver.cs
@@ -68,7 +68,7 @@ public sealed class FocasDriver : IDriver, IReadable, IWritable, ITagDiscovery,
         _logger = logger ?? NullLogger<FocasDriver>.Instance;
         _resolver = new EquipmentTagRefResolver<FocasTagDefinition>(
             r => _tagsByName.TryGetValue(r, out var t) ? t : null,
-            r => FocasEquipmentTagParser.TryParse(r, out var d) ? d : null);
+            ResolveEquipmentTagRef);
         _poll = new PollGroupEngine(
             reader: ReadAsync,
             onChange: (handle, tagRef, snapshot) =>
@@ -234,6 +234,20 @@ public sealed class FocasDriver : IDriver, IReadable, IWritable, ITagDiscovery,
     internal bool IsParsedAddressCached(string reference) =>
         _parsedAddressesByTagName.ContainsKey(reference);
 
+    // Resolves an equipment-tag TagConfig reference into a FocasTagDefinition, applying the SAME
+    // capability pre-flight authored tags get at InitializeAsync (:105-119) — R2-11 (05/UNDER-6). A
+    // reference whose address is unparseable, whose bound device is unknown, or whose address violates
+    // the device series' capability matrix returns null ⇒ resolver miss ⇒ BadNodeIdUnknown at read time,
+    // instead of a wrong-status read reaching the wire. The negative is cached by the resolver.
+    private FocasTagDefinition? ResolveEquipmentTagRef(string reference)
+    {
+        if (!FocasEquipmentTagParser.TryParse(reference, out var def)) return null;
+        var parsed = FocasAddress.TryParse(def.Address);
+        if (parsed is null) return null;
+        if (!_devices.TryGetValue(def.DeviceHostAddress, out var device)) return null;
+        return FocasCapabilityMatrix.Validate(device.Options.Series, parsed) is null ? def : null;
+    }
+
     // Resolves a tag definition to its parsed FocasAddress, caching the result so that
     // equipment tags (resolver-produced, not seeded at InitializeAsync) don't re-parse the
     // address string on every ReadAsync / WriteAsync hot-path call.
diff --git a/tests/Drivers/ZB.MOM.WW.OtOpcUa.Driver.FOCAS.Tests/FocasEquipmentTagCapabilityGateTests.cs b/tests/Drivers/ZB.MOM.WW.OtOpcUa.Driver.FOCAS.Tests/FocasEquipmentTagCapabilityGateTests.cs
new file mode 100644
index 00000000..bda91d72
--- /dev/null
+++ b/tests/Drivers/ZB.MOM.WW.OtOpcUa.Driver.FOCAS.Tests/FocasEquipmentTagCapabilityGateTests.cs
@@ -0,0 +1,61 @@
+using Shouldly;
+using Xunit;
+using ZB.MOM.WW.OtOpcUa.Driver.FOCAS;
+
+namespace ZB.MOM.WW.OtOpcUa.Driver.FOCAS.Tests;
+
+/// <summary>
+///     R2-11 (05/UNDER-6): an equipment-tag reference whose address violates the device series'
+///     capability matrix must fail to RESOLVE (surfacing <c>BadNodeIdUnknown</c>) — the same pre-flight
+///     authored tags get at <c>InitializeAsync</c> — instead of reaching the wire and failing later with a
+///     wire error. A capability-valid equipment tag still resolves + reads.
+/// </summary>
+[Trait("Category", "Unit")]
+public sealed class FocasEquipmentTagCapabilityGateTests
+{
+    private const string Host = "focas://10.0.0.5:8193";
+
+    private static FocasDriver NewDriver() => new(new FocasDriverOptions
+    {
+        // Series 16i: macro range 0..999 — MACRO:9500 is out of range.
+        Devices = [new FocasDeviceOptions(Host, Series: FocasCncSeries.Sixteen_i)],
+        Probe = new FocasProbeOptions { Enabled = false },
+    }, "drv-1", new FakeFocasClientFactory());
+
+    private static string EquipTag(string address) =>
+        $"{{\"address\":\"{address}\",\"dataType\":\"Int32\",\"deviceHostAddress\":\"{Host}\"}}";
+
+    [Fact]
+    public async Task Capability_violating_equipment_tag_does_not_resolve()
+    {
+        var drv = NewDriver();
+        await drv.InitializeAsync("{}", CancellationToken.None);
+
+        var results = await drv.ReadAsync([EquipTag("MACRO:9500")], CancellationToken.None);
+
+        results.Single().StatusCode.ShouldBe(FocasStatusMapper.BadNodeIdUnknown);
+    }
+
+    [Fact]
+    public async Task Capability_valid_equipment_tag_resolves_and_reads()
+    {
+        var drv = NewDriver();
+        await drv.InitializeAsync("{}", CancellationToken.None);
+
+        var results = await drv.ReadAsync([EquipTag("MACRO:100")], CancellationToken.None);
+
+        results.Single().StatusCode.ShouldNotBe(FocasStatusMapper.BadNodeIdUnknown);
+    }
+
+    [Fact]
+    public async Task Equipment_tag_for_unknown_device_does_not_resolve()
+    {
+        var drv = NewDriver();
+        await drv.InitializeAsync("{}", CancellationToken.None);
+
+        var badDevice = "{\"address\":\"MACRO:100\",\"dataType\":\"Int32\",\"deviceHostAddress\":\"focas://10.9.9.9:8193\"}";
+        var results = await drv.ReadAsync([badDevice], CancellationToken.None);
+
+        results.Single().StatusCode.ShouldBe(FocasStatusMapper.BadNodeIdUnknown);
+    }
+}