diff --git a/secretmanager/api/SecretManager.Samples.Tests/CreateRegionalSecretWithExpirationTests.cs b/secretmanager/api/SecretManager.Samples.Tests/CreateRegionalSecretWithExpirationTests.cs
new file mode 100644
index 00000000000..cd96835d4b3
--- /dev/null
+++ b/secretmanager/api/SecretManager.Samples.Tests/CreateRegionalSecretWithExpirationTests.cs
@@ -0,0 +1,56 @@
+/*
+ * Copyright 2026 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+using Google.Cloud.SecretManager.V1;
+using System;
+using System.IO;
+using Xunit;
+
+[Collection(nameof(RegionalSecretManagerFixture))]
+public class CreateRegionalSecretWithExpireTimeTests
+{
+    private readonly RegionalSecretManagerFixture _fixture;
+    private readonly CreateRegionalSecretWithExpireTimeSample _sample;
+
+    public CreateRegionalSecretWithExpireTimeTests(RegionalSecretManagerFixture fixture)
+    {
+        _fixture = fixture;
+        _sample = new CreateRegionalSecretWithExpireTimeSample();
+    }
+
+    [Fact]
+    public void CreatesRegionalSecretWithExpireTime()
+    {
+        // Get the SecretName from the set ProjectId & LocationId.
+        SecretName secretName = SecretName.FromProjectLocationSecret(
+            _fixture.ProjectId, _fixture.LocationId, _fixture.RandomId());
+        try
+        {
+            // Run the code sample.
+            Secret result = _sample.CreateRegionalSecretWithExpireTime(
+                projectId: secretName.ProjectId,
+                secretId: secretName.SecretId,
+                locationId: secretName.LocationId);
+
+            Assert.NotNull(result.ExpireTime);
+        }
+        finally
+        {
+            // Clean the created secret.
+            _fixture.DeleteSecret(secretName);
+        }
+    }
+}
diff --git a/secretmanager/api/SecretManager.Samples.Tests/CreateSecretWithExpirationTests.cs b/secretmanager/api/SecretManager.Samples.Tests/CreateSecretWithExpirationTests.cs
new file mode 100644
index 00000000000..6929350720d
--- /dev/null
+++ b/secretmanager/api/SecretManager.Samples.Tests/CreateSecretWithExpirationTests.cs
@@ -0,0 +1,54 @@
+/*
+ * Copyright 2026 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+using Google.Cloud.SecretManager.V1;
+using Google.Protobuf.WellKnownTypes;
+using System;
+using System.IO;
+using Xunit;
+
+[Collection(nameof(SecretManagerFixture))]
+public class CreateSecretWithExpirationTests
+{
+    private readonly SecretManagerFixture _fixture;
+    private readonly CreateSecretWithExpirationSample _sample;
+
+    public CreateSecretWithExpirationTests(SecretManagerFixture fixture)
+    {
+        _fixture = fixture;
+        _sample = new CreateSecretWithExpirationSample();
+    }
+
+    [Fact]
+    public void CreatesSecretWithExpiration()
+    {
+        // Get the SecretName to create Secret.
+        SecretName secretName = new SecretName(_fixture.ProjectId, _fixture.RandomId());
+        try
+        {
+            // Create the secret with expiration.
+            Secret result = _sample.CreateSecretWithExpiration(
+              projectId: secretName.ProjectId, secretId: secretName.SecretId);
+
+            Assert.NotNull(result.ExpireTime);
+        }
+        finally
+        {
+            // Clean the created secret.
+            _fixture.DeleteSecret(secretName);
+        }
+    }
+}
diff --git a/secretmanager/api/SecretManager.Samples.Tests/DeleteRegionalSecretAnnotationTests.cs b/secretmanager/api/SecretManager.Samples.Tests/DeleteRegionalSecretAnnotationTests.cs
new file mode 100644
index 00000000000..850c2d75ed3
--- /dev/null
+++ b/secretmanager/api/SecretManager.Samples.Tests/DeleteRegionalSecretAnnotationTests.cs
@@ -0,0 +1,63 @@
+/*
+ * Copyright 2026 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+using Google.Cloud.SecretManager.V1;
+using System;
+using System.IO;
+using Xunit;
+
+[Collection(nameof(RegionalSecretManagerFixture))]
+public class DeleteRegionalSecretAnnotationTests
+{
+    private readonly RegionalSecretManagerFixture _fixture;
+    private readonly DeleteRegionalSecretAnnotationSample _sample;
+
+    public DeleteRegionalSecretAnnotationTests(RegionalSecretManagerFixture fixture)
+    {
+        _fixture = fixture;
+        _sample = new DeleteRegionalSecretAnnotationSample();
+    }
+
+    [Fact]
+    public void DeleteRegionalSecretAnnotation()
+    {
+        // Create a secret with annotations
+        Secret secret = _fixture.CreateSecret(_fixture.RandomId());
+        SecretName secretName = secret.SecretName;
+        try
+        {
+            // Get a key from the existing annotations
+            string annotationKey = _fixture.AnnotationKey;
+
+            // Verify the secret has annotations
+            Assert.NotEmpty(secret.Annotations);
+            Assert.True(secret.Annotations.ContainsKey(annotationKey));
+
+            // Run the sample code to delete the annotation
+            Secret result = _sample.DeleteRegionalSecretAnnotation(
+                projectId: secretName.ProjectId,
+                locationId: secretName.LocationId,
+                secretId: secretName.SecretId);
+
+            Assert.Empty(result.Annotations);
+        }
+        finally
+        {
+            // Clean the created secret.
+            _fixture.DeleteSecret(secretName);
+        }
+    }
+}
diff --git a/secretmanager/api/SecretManager.Samples.Tests/DeleteRegionalSecretExpirationTests.cs b/secretmanager/api/SecretManager.Samples.Tests/DeleteRegionalSecretExpirationTests.cs
new file mode 100644
index 00000000000..0604bbde140
--- /dev/null
+++ b/secretmanager/api/SecretManager.Samples.Tests/DeleteRegionalSecretExpirationTests.cs
@@ -0,0 +1,55 @@
+/*
+ * Copyright 2026 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+using Google.Cloud.SecretManager.V1;
+using Google.Protobuf.WellKnownTypes;
+using System;
+using System.IO;
+using Xunit;
+
+[Collection(nameof(RegionalSecretManagerFixture))]
+public class DeleteRegionalSecretExpirationTests
+{
+    private readonly RegionalSecretManagerFixture _fixture;
+    private readonly DeleteRegionalSecretExpirationSample _deleteSample;
+
+    public DeleteRegionalSecretExpirationTests(RegionalSecretManagerFixture fixture)
+    {
+        _fixture = fixture;
+        _deleteSample = new DeleteRegionalSecretExpirationSample();
+    }
+
+    [Fact]
+    public void DeletesRegionalSecretExpiration()
+    {
+        Secret initialSecret = _fixture.CreateSecretWithExpireTime();
+        try
+        {
+            // Delete the expiration time
+            Secret result = _deleteSample.DeleteRegionalSecretExpiration(
+                projectId: initialSecret.SecretName.ProjectId,
+                secretId: initialSecret.SecretName.SecretId,
+                locationId: initialSecret.SecretName.LocationId);
+
+            Assert.Null(result.ExpireTime);
+        }
+        finally
+        {
+            // Clean the created secret
+            _fixture.DeleteSecret(initialSecret.SecretName);
+        }
+    }
+}
diff --git a/secretmanager/api/SecretManager.Samples.Tests/DeleteRegionalSecretLabelTests.cs b/secretmanager/api/SecretManager.Samples.Tests/DeleteRegionalSecretLabelTests.cs
new file mode 100644
index 00000000000..6c52ee3cae7
--- /dev/null
+++ b/secretmanager/api/SecretManager.Samples.Tests/DeleteRegionalSecretLabelTests.cs
@@ -0,0 +1,59 @@
+/*
+ * Copyright 2026 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+using Google.Cloud.SecretManager.V1;
+using System;
+using System.IO;
+using Xunit;
+
+[Collection(nameof(RegionalSecretManagerFixture))]
+public class DeleteRegionalSecretLabelTests
+{
+    private readonly RegionalSecretManagerFixture _fixture;
+    private readonly DeleteRegionalSecretLabelSample _sample;
+
+    public DeleteRegionalSecretLabelTests(RegionalSecretManagerFixture fixture)
+    {
+        _fixture = fixture;
+        _sample = new DeleteRegionalSecretLabelSample();
+    }
+
+    [Fact]
+    public void DeleteRegionalSecretLabel()
+    {
+        Secret secret = _fixture.CreateSecret(_fixture.RandomId());
+        SecretName secretName = secret.SecretName;
+        try
+        {
+            // Verify the secret has labels
+            Assert.NotEmpty(secret.Labels);
+
+            // Run the sample code to delete all labels
+            Secret result = _sample.DeleteRegionalSecretLabel(
+
+                projectId: secretName.ProjectId,
+                locationId: secretName.LocationId,
+                secretId: secretName.SecretId);
+
+            Assert.Empty(result.Labels);
+        }
+        finally
+        {
+            // Clean the created secret.
+            _fixture.DeleteSecret(secretName);
+        }
+    }
+}
diff --git a/secretmanager/api/SecretManager.Samples.Tests/DeleteSecretAnnotationTests.cs b/secretmanager/api/SecretManager.Samples.Tests/DeleteSecretAnnotationTests.cs
new file mode 100644
index 00000000000..b7ffc00c47c
--- /dev/null
+++ b/secretmanager/api/SecretManager.Samples.Tests/DeleteSecretAnnotationTests.cs
@@ -0,0 +1,57 @@
+/*
+ * Copyright 2026 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+using Google.Cloud.SecretManager.V1;
+using System;
+using System.IO;
+using Xunit;
+
+[Collection(nameof(SecretManagerFixture))]
+public class DeleteSecretAnnotationTests
+{
+    private readonly SecretManagerFixture _fixture;
+    private readonly DeleteSecretAnnotationSample _sample;
+
+    public DeleteSecretAnnotationTests(SecretManagerFixture fixture)
+    {
+        _fixture = fixture;
+        _sample = new DeleteSecretAnnotationSample();
+    }
+
+    [Fact]
+    public void DeleteSecretAnnotation()
+    {
+        // Create the secret.
+        Secret secret = _fixture.CreateSecret(_fixture.RandomId());
+        // Get the secretName from the created secret.
+        SecretName secretName = secret.SecretName;
+        try
+        {
+            Assert.NotEmpty(secret.Annotations);
+            // Call the code sample function to delete the annotations
+            Secret result = _sample.DeleteSecretAnnotation(
+              projectId: secretName.ProjectId, secretId: secretName.SecretId);
+
+            // Assert that the label is deleted.
+            Assert.Empty(result.Annotations);
+        }
+        finally
+        {
+            // Clean the created secret.
+            _fixture.DeleteSecret(secretName);
+        }
+    }
+}
diff --git a/secretmanager/api/SecretManager.Samples.Tests/DeleteSecretExpirationTests.cs b/secretmanager/api/SecretManager.Samples.Tests/DeleteSecretExpirationTests.cs
new file mode 100644
index 00000000000..191aca84657
--- /dev/null
+++ b/secretmanager/api/SecretManager.Samples.Tests/DeleteSecretExpirationTests.cs
@@ -0,0 +1,54 @@
+/*
+ * Copyright 2026 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+using Google.Cloud.SecretManager.V1;
+using Google.Protobuf.WellKnownTypes;
+using System;
+using System.IO;
+using Xunit;
+
+[Collection(nameof(SecretManagerFixture))]
+public class DeleteSecretExpirationTests
+{
+    private readonly SecretManagerFixture _fixture;
+    private readonly DeleteSecretExpirationSample _deleteSample;
+
+    public DeleteSecretExpirationTests(SecretManagerFixture fixture)
+    {
+        _fixture = fixture;
+        _deleteSample = new DeleteSecretExpirationSample();
+    }
+
+    [Fact]
+    public void DeletesSecretExpiration()
+    {
+        // First, create a secret with an expiration time
+        Secret secret = _fixture.CreateSecretWithExpiration();
+        try
+        {
+            // Delete the expiration time
+            Secret result = _deleteSample.DeleteSecretExpiration(
+                projectId: secret.SecretName.ProjectId, secretId: secret.SecretName.SecretId);
+
+            Assert.Null(result.ExpireTime);
+        }
+        finally
+        {
+            // Clean up the created secret
+            _fixture.DeleteSecret(secret.SecretName);
+        }
+    }
+}
diff --git a/secretmanager/api/SecretManager.Samples.Tests/DeleteSecretLabelTests.cs b/secretmanager/api/SecretManager.Samples.Tests/DeleteSecretLabelTests.cs
new file mode 100644
index 00000000000..7bc8bee0c03
--- /dev/null
+++ b/secretmanager/api/SecretManager.Samples.Tests/DeleteSecretLabelTests.cs
@@ -0,0 +1,58 @@
+/*
+ * Copyright 2026 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+using Google.Cloud.SecretManager.V1;
+using System;
+using System.IO;
+using Xunit;
+
+[Collection(nameof(SecretManagerFixture))]
+public class DeleteSecretLabelTests
+{
+    private readonly SecretManagerFixture _fixture;
+    private readonly DeleteSecretLabelSample _sample;
+
+    public DeleteSecretLabelTests(SecretManagerFixture fixture)
+    {
+        _fixture = fixture;
+        _sample = new DeleteSecretLabelSample();
+    }
+
+    [Fact]
+    public void DeleteSecretLabel()
+    {
+        // Create the secret.
+        Secret secret = _fixture.CreateSecret(_fixture.RandomId());
+
+        // Get the secretName from the created secret.
+        SecretName secretName = secret.SecretName;
+        try
+        {
+            Assert.NotEmpty(secret.Labels);
+            // Call the code sample function to delete the label
+            Secret result = _sample.DeleteSecretLabel(
+              projectId: secretName.ProjectId, secretId: secretName.SecretId);
+
+            // Assert that the label is deleted.
+            Assert.Empty(result.Labels);
+        }
+        finally
+        {
+            // Clean the created secret.
+            _fixture.DeleteSecret(secretName);
+        }
+    }
+}
diff --git a/secretmanager/api/SecretManager.Samples.Tests/EditSecretLabelTests.cs b/secretmanager/api/SecretManager.Samples.Tests/EditSecretLabelTests.cs
new file mode 100644
index 00000000000..6da6560a7dd
--- /dev/null
+++ b/secretmanager/api/SecretManager.Samples.Tests/EditSecretLabelTests.cs
@@ -0,0 +1,46 @@
+/*
+ * Copyright 2026 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+using Google.Cloud.SecretManager.V1;
+using System;
+using System.IO;
+using Xunit;
+
+[Collection(nameof(SecretManagerFixture))]
+public class EditSecretLabelTests
+{
+    private readonly SecretManagerFixture _fixture;
+    private readonly EditSecretLabelSample _sample;
+
+    public EditSecretLabelTests(SecretManagerFixture fixture)
+    {
+        _fixture = fixture;
+        _sample = new EditSecretLabelSample();
+    }
+
+    [Fact]
+    public void EditSecretLabel()
+    {
+        // Get the SecretName to create Secret.
+        SecretName secretName = _fixture.Secret.SecretName;
+
+        // Call the code sample function.
+        Secret result = _sample.EditSecretLabel(
+          projectId: secretName.ProjectId, secretId: secretName.SecretId);
+
+        Assert.Equal("my-label-value", result.Labels["my-label-key"]);
+    }
+}
diff --git a/secretmanager/api/SecretManager.Samples.Tests/ListSecretVersionsWithFilterTests.cs b/secretmanager/api/SecretManager.Samples.Tests/ListSecretVersionsWithFilterTests.cs
new file mode 100644
index 00000000000..cd50cced3e8
--- /dev/null
+++ b/secretmanager/api/SecretManager.Samples.Tests/ListSecretVersionsWithFilterTests.cs
@@ -0,0 +1,66 @@
+/*
+ * Copyright 2026 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+using System;
+using System.IO;
+using System.Collections.Generic;
+using Xunit;
+using Google.Cloud.SecretManager.V1;
+
+[Collection(nameof(SecretManagerFixture))]
+public class ListSecretVersionsWithFilterTests
+{
+    private readonly SecretManagerFixture _fixture;
+    private readonly ListSecretVersionsWithFilterSample _sample;
+
+    public ListSecretVersionsWithFilterTests(SecretManagerFixture fixture)
+    {
+        _fixture = fixture;
+        _sample = new ListSecretVersionsWithFilterSample();
+    }
+
+    [Fact]
+    public void ListSecretVersionsWithFilter()
+    {
+        // Create the secret resource.
+        Secret secret = _fixture.CreateSecret(_fixture.RandomId());
+
+        // Get the SecretName.
+        SecretName secretName = secret.SecretName;
+
+        // Run the code sample.
+        SecretVersion secretVersion = _fixture.AddSecretVersion(secret);
+        _fixture.DisableSecretVersion(secretVersion);
+
+        // Run the sample code
+        IList<SecretVersion> versions = _sample.ListSecretVersionsWithFilter(
+             projectId: secretName.ProjectId,
+             secretId: secretName.SecretId);
+
+        // Verify we got results
+        Assert.NotNull(versions);
+        Assert.NotEmpty(versions);
+
+        // Verify only disabled versions are returned
+        foreach (var version in versions)
+        {
+            Assert.Equal(SecretVersion.Types.State.Disabled, version.State);
+        }
+
+        // Clean the created secret.
+        _fixture.DeleteSecret(secretName);
+    }
+}
diff --git a/secretmanager/api/SecretManager.Samples.Tests/ListSecretsWithFilterTests.cs b/secretmanager/api/SecretManager.Samples.Tests/ListSecretsWithFilterTests.cs
new file mode 100644
index 00000000000..058bf163ccd
--- /dev/null
+++ b/secretmanager/api/SecretManager.Samples.Tests/ListSecretsWithFilterTests.cs
@@ -0,0 +1,59 @@
+/*
+ * Copyright 2026 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+using System;
+using System.IO;
+using System.Collections.Generic;
+using Xunit;
+using Google.Cloud.SecretManager.V1;
+using System.Linq;
+
+[Collection(nameof(SecretManagerFixture))]
+public class ListSecretsWithFilterTests
+{
+    private readonly SecretManagerFixture _fixture;
+    private readonly ListSecretsWithFilterSample _sample;
+
+    public ListSecretsWithFilterTests(SecretManagerFixture fixture)
+    {
+        _fixture = fixture;
+        _sample = new ListSecretsWithFilterSample();
+    }
+
+    [Fact]
+    public void ListsSecretsWithFilter()
+    {
+        Secret secret = _fixture.CreateSecret(_fixture.RandomId());
+        SecretName secretName = secret.SecretName;
+        try
+        {
+            IList<Secret> secrets = _sample.ListSecretsWithFilter(
+                        projectId: _fixture.ProjectId);
+
+            // Verify we got results
+            Assert.NotNull(secrets);
+            Assert.NotEmpty(secrets);
+
+            // Verify our specific secret is in the results
+            bool foundSecret = secrets.Any(s => s.SecretName.SecretId == secretName.SecretId);
+            Assert.True(foundSecret, $"The secret {secretName.SecretId} with label my-label-key=my-label-value should be in the results");
+        }
+        finally
+        {
+            _fixture.DeleteSecret(secretName);
+        }
+    }
+}
diff --git a/secretmanager/api/SecretManager.Samples.Tests/RegionalSecretManagerFixture.cs b/secretmanager/api/SecretManager.Samples.Tests/RegionalSecretManagerFixture.cs
index 6451b6c97cc..72224a1d980 100644
--- a/secretmanager/api/SecretManager.Samples.Tests/RegionalSecretManagerFixture.cs
+++ b/secretmanager/api/SecretManager.Samples.Tests/RegionalSecretManagerFixture.cs
@@ -32,6 +32,8 @@ public class RegionalSecretManagerFixture : IDisposable, ICollectionFixture<Regi
     public string LabelValue { get; }
     public Secret Secret { get; }
     public SecretVersion SecretVersion { get; }
+    public string KmsKeyName { get; }
+
     public RegionalSecretManagerFixture()
     {
         // Get the Google Cloud ProjectId
@@ -41,6 +43,12 @@ public RegionalSecretManagerFixture()
             throw new Exception("missing GOOGLE_PROJECT_ID");
         }
 
+        KmsKeyName = Environment.GetEnvironmentVariable("GOOGLE_CLOUD_REGIONAL_KMS_KEY_NAME");
+        if (String.IsNullOrEmpty(KmsKeyName))
+        {
+            throw new Exception("missing GOOGLE_CLOUD_REGIONAL_KMS_KEY_NAME");
+        }
+
         // Get LocationId (e.g., "us-west1")
         LocationId = Environment.GetEnvironmentVariable("GOOGLE_CLOUD_LOCATION") ?? "us-west1";
 
@@ -105,6 +113,21 @@ public Secret CreateSecretWithDelayedDestroy()
         return Client.CreateSecret(locationName, RandomId(), secret);
     }
 
+    public Secret CreateSecretWithExpireTime()
+    {
+        LocationName locationName = new LocationName(ProjectId, LocationId);
+
+        DateTime expireTime = DateTime.UtcNow.AddHours(1);
+        Timestamp timestamp = Timestamp.FromDateTime(expireTime);
+
+        Secret secret = new Secret
+        {
+            ExpireTime = timestamp
+        };
+
+        return Client.CreateSecret(locationName, RandomId(), secret);
+    }
+
     public SecretVersion AddSecretVersion(Secret secret)
     {
         SecretPayload payload = new SecretPayload
diff --git a/secretmanager/api/SecretManager.Samples.Tests/SecretManagerFixture.cs b/secretmanager/api/SecretManager.Samples.Tests/SecretManagerFixture.cs
index 82fa8d99691..0881090f790 100644
--- a/secretmanager/api/SecretManager.Samples.Tests/SecretManagerFixture.cs
+++ b/secretmanager/api/SecretManager.Samples.Tests/SecretManagerFixture.cs
@@ -34,6 +34,7 @@ public class SecretManagerFixture : IDisposable, ICollectionFixture<SecretManage
     public string AnnotationValue { get; }
     public string LabelKey { get; }
     public string LabelValue { get; }
+    public string KmsKeyName { get; }
 
     public SecretManagerFixture()
     {
@@ -44,6 +45,12 @@ public SecretManagerFixture()
             throw new Exception("missing GOOGLE_PROJECT_ID");
         }
 
+        KmsKeyName = Environment.GetEnvironmentVariable("GOOGLE_CLOUD_KMS_KEY_NAME");
+        if (String.IsNullOrEmpty(KmsKeyName))
+        {
+            throw new Exception("missing GOOGLE_CLOUD_KMS_KEY_NAME");
+        }
+
         // Get the ProjectName from ProjectId,
         ProjectName = new ProjectName(ProjectId);
 
@@ -110,6 +117,24 @@ public Secret CreateSecretWithDelayedDestroy()
         return Client.CreateSecret(ProjectName, RandomId(), secret);
     }
 
+    public Secret CreateSecretWithExpiration()
+    {
+        DateTime expireTime = DateTime.UtcNow.AddHours(1);
+        Timestamp timestamp = Timestamp.FromDateTime(expireTime.ToUniversalTime());
+
+        // Build the secret with automatic replication and expiration time.
+        Secret secret = new Secret
+        {
+            Replication = new Replication
+            {
+                Automatic = new Replication.Types.Automatic(),
+            },
+            ExpireTime = timestamp
+        };
+
+        return Client.CreateSecret(ProjectName, RandomId(), secret);
+    }
+
     public SecretVersion AddSecretVersion(Secret secret)
     {
         SecretPayload payload = new SecretPayload
diff --git a/secretmanager/api/SecretManager.Samples.Tests/UpdateRegionalSecretExpirationTests.cs b/secretmanager/api/SecretManager.Samples.Tests/UpdateRegionalSecretExpirationTests.cs
new file mode 100644
index 00000000000..6c642670131
--- /dev/null
+++ b/secretmanager/api/SecretManager.Samples.Tests/UpdateRegionalSecretExpirationTests.cs
@@ -0,0 +1,63 @@
+/*
+ * Copyright 2026 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+using Google.Cloud.SecretManager.V1;
+using System;
+using System.IO;
+using Xunit;
+
+[Collection(nameof(RegionalSecretManagerFixture))]
+public class UpdateRegionalSecretExpirationTests
+{
+    private readonly RegionalSecretManagerFixture _fixture;
+    private readonly UpdateRegionalSecretExpirationSample _updateSample;
+
+    public UpdateRegionalSecretExpirationTests(RegionalSecretManagerFixture fixture)
+    {
+        _fixture = fixture;
+        _updateSample = new UpdateRegionalSecretExpirationSample();
+    }
+
+    [Fact]
+    public void UpdatesRegionalSecretExpiration()
+    {
+
+        // First, create a secret with initial expiration time (1 hour)
+        Secret initialSecret = _fixture.CreateSecretWithExpireTime();
+        try
+        {
+            // Update the secret to have a 2-hour expiration
+            Secret result = _updateSample.UpdateRegionalSecretExpiration(
+                projectId: initialSecret.SecretName.ProjectId,
+                secretId: initialSecret.SecretName.SecretId,
+                locationId: initialSecret.SecretName.LocationId);
+
+            DateTime expectedTime = DateTime.UtcNow.AddHours(2);
+            DateTime actualTime = result.ExpireTime.ToDateTime();
+
+            // Allow for a small time difference (e.g., 30 seconds) due to test execution
+            Assert.True(
+                (actualTime - expectedTime).Duration() < TimeSpan.FromSeconds(60),
+                $"Expected expiration time around {expectedTime}, but got {actualTime}"
+            );
+        }
+        finally
+        {
+            // Clean the created secret
+            _fixture.DeleteSecret(initialSecret.SecretName);
+        }
+    }
+}
diff --git a/secretmanager/api/SecretManager.Samples.Tests/UpdateSecretExpirationTests.cs b/secretmanager/api/SecretManager.Samples.Tests/UpdateSecretExpirationTests.cs
new file mode 100644
index 00000000000..36fafa64e48
--- /dev/null
+++ b/secretmanager/api/SecretManager.Samples.Tests/UpdateSecretExpirationTests.cs
@@ -0,0 +1,63 @@
+/*
+ * Copyright 2026 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+using Google.Cloud.SecretManager.V1;
+using Google.Protobuf.WellKnownTypes;
+using System;
+using System.IO;
+using Xunit;
+
+[Collection(nameof(SecretManagerFixture))]
+public class UpdateSecretExpirationTests
+{
+    private readonly SecretManagerFixture _fixture;
+    private readonly UpdateSecretExpirationSample _sample;
+
+    public UpdateSecretExpirationTests(SecretManagerFixture fixture)
+    {
+        _fixture = fixture;
+        _sample = new UpdateSecretExpirationSample();
+    }
+
+    [Fact]
+    public void UpdatesSecretExpiration()
+    {
+
+        // Create a new secret with no expiration time
+        Secret secret = _fixture.CreateSecretWithExpiration();
+        try
+        {
+            // Update the secret with an expiration time
+            Secret result = _sample.UpdateSecretExpiration(
+                projectId: secret.SecretName.ProjectId,
+                secretId: secret.SecretName.SecretId);
+
+            DateTime expectedTime = DateTime.UtcNow.AddHours(2);
+            DateTime actualTime = result.ExpireTime.ToDateTime();
+
+            // Allow for a small time difference (e.g., 30 seconds) due to test execution
+            Assert.True(
+                (actualTime - expectedTime).Duration() < TimeSpan.FromSeconds(60),
+                $"Expected expiration time around {expectedTime}, but got {actualTime}"
+            );
+        }
+        finally
+        {
+            // Clean up the created secret
+            _fixture.DeleteSecret(secret.SecretName);
+        }
+    }
+}
diff --git a/secretmanager/api/SecretManager.Samples.Tests/createRegionalSecretWithCmekTests.cs b/secretmanager/api/SecretManager.Samples.Tests/createRegionalSecretWithCmekTests.cs
new file mode 100644
index 00000000000..aa3f071a79a
--- /dev/null
+++ b/secretmanager/api/SecretManager.Samples.Tests/createRegionalSecretWithCmekTests.cs
@@ -0,0 +1,62 @@
+/*
+ * Copyright 2026 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+using Google.Cloud.SecretManager.V1;
+using System;
+using System.IO;
+using Xunit;
+
+[Collection(nameof(RegionalSecretManagerFixture))]
+public class CreateRegionalSecretWithCmekTests
+{
+    private readonly RegionalSecretManagerFixture _fixture;
+    private readonly CreateRegionalSecretWithCmekSample _sample;
+
+    public CreateRegionalSecretWithCmekTests(RegionalSecretManagerFixture fixture)
+    {
+        _fixture = fixture;
+        _sample = new CreateRegionalSecretWithCmekSample();
+    }
+
+    [Fact]
+    public void CreatesRegionalSecretWithCmek()
+    {
+        // Skip the test if no regional KMS key is available
+        if (string.IsNullOrEmpty(_fixture.KmsKeyName))
+        {
+            return;
+        }
+
+        // Get the SecretName from the set ProjectId & LocationId.
+        SecretName secretName = SecretName.FromProjectLocationSecret(_fixture.ProjectId, _fixture.LocationId, _fixture.RandomId());
+        try
+        {
+            // Create the regional secret with CMEK.
+            Secret result = _sample.CreateRegionalSecretWithCmek(
+                projectId: secretName.ProjectId,
+                locationId: secretName.LocationId,
+                secretId: secretName.SecretId,
+                kmsKeyName: _fixture.KmsKeyName);
+
+            Assert.Equal(result.CustomerManagedEncryption.KmsKeyName, _fixture.KmsKeyName);
+        }
+        finally
+        {
+            // Clean the created secret.
+            _fixture.DeleteSecret(secretName);
+        }
+    }
+}
diff --git a/secretmanager/api/SecretManager.Samples.Tests/createSecretWithCmekTests.cs b/secretmanager/api/SecretManager.Samples.Tests/createSecretWithCmekTests.cs
new file mode 100644
index 00000000000..4f5caf14534
--- /dev/null
+++ b/secretmanager/api/SecretManager.Samples.Tests/createSecretWithCmekTests.cs
@@ -0,0 +1,63 @@
+/*
+ * Copyright 2026 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+using Google.Cloud.SecretManager.V1;
+using Microsoft.VisualBasic;
+using System;
+using System.IO;
+using Xunit;
+
+[Collection(nameof(SecretManagerFixture))]
+public class CreateSecretWithCmekTests
+{
+    private readonly SecretManagerFixture _fixture;
+    private readonly CreateSecretWithCmekSample _sample;
+
+    public CreateSecretWithCmekTests(SecretManagerFixture fixture)
+    {
+        _fixture = fixture;
+        _sample = new CreateSecretWithCmekSample();
+    }
+
+    [Fact]
+    public void CreatesSecretWithCmek()
+    {
+        // Skip the test if no KMS key is available
+        if (string.IsNullOrEmpty(_fixture.KmsKeyName))
+        {
+            return;
+        }
+
+        // Get the SecretName to create Secret.
+        SecretName secretName = new SecretName(_fixture.ProjectId, _fixture.RandomId());
+        try
+        {
+            // Create the secret with CMEK.
+            Secret result = _sample.CreateSecretWithCmek(
+                projectId: secretName.ProjectId,
+                secretId: secretName.SecretId,
+                kmsKeyName: _fixture.KmsKeyName);
+
+            Assert.Equal(result.Replication.Automatic.CustomerManagedEncryption.KmsKeyName, _fixture.KmsKeyName);
+        }
+        finally
+        {
+            // Clean the created secret.
+            _fixture.DeleteSecret(secretName);
+        }
+
+    }
+}
diff --git a/secretmanager/api/SecretManager.Samples/CreateRegionalSecretWithExpiration.cs b/secretmanager/api/SecretManager.Samples/CreateRegionalSecretWithExpiration.cs
new file mode 100644
index 00000000000..5dcd9c28ca7
--- /dev/null
+++ b/secretmanager/api/SecretManager.Samples/CreateRegionalSecretWithExpiration.cs
@@ -0,0 +1,59 @@
+/*
+ * Copyright 2025 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// [START secretmanager_create_regional_secret_with_expire_time]
+
+using Google.Api.Gax.ResourceNames;
+using Google.Cloud.SecretManager.V1;
+using Google.Protobuf.WellKnownTypes;
+using System;
+
+public class CreateRegionalSecretWithExpireTimeSample
+{
+    public Secret CreateRegionalSecretWithExpireTime(
+        string projectId = "my-project",
+        string secretId = "my-secret-with-expiry",
+        string locationId = "us-central1")
+    {
+        // Set expiration time to 1 hour from now
+        DateTime expireTime = DateTime.UtcNow.AddHours(1);
+
+        // Create the Regional Secret Manager Client.
+        SecretManagerServiceClient client = new SecretManagerServiceClientBuilder
+        {
+            Endpoint = $"secretmanager.{locationId}.rep.googleapis.com"
+        }.Build();
+
+        // Build the parent resource name.
+        LocationName location = new LocationName(projectId, locationId);
+
+        // Convert DateTime to Timestamp
+        Timestamp timestamp = Timestamp.FromDateTime(expireTime);
+
+        // Build the secret with expiration time
+        Secret secret = new Secret
+        {
+            ExpireTime = timestamp
+        };
+
+        // Call the API.
+        Secret createdSecret = client.CreateSecret(location, secretId, secret);
+
+        Console.WriteLine($"Created secret {createdSecret.SecretName} with expiration time {expireTime}");
+        return createdSecret;
+    }
+}
+// [END secretmanager_create_regional_secret_with_expire_time]
diff --git a/secretmanager/api/SecretManager.Samples/CreateSecretWithExpiration.cs b/secretmanager/api/SecretManager.Samples/CreateSecretWithExpiration.cs
new file mode 100644
index 00000000000..fc756e54951
--- /dev/null
+++ b/secretmanager/api/SecretManager.Samples/CreateSecretWithExpiration.cs
@@ -0,0 +1,57 @@
+/*
+ * Copyright 2026 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// [START secretmanager_create_secret_with_expiration]
+
+using Google.Api.Gax.ResourceNames;
+using Google.Cloud.SecretManager.V1;
+using Google.Protobuf.WellKnownTypes;
+using System;
+
+public class CreateSecretWithExpirationSample
+{
+    public Secret CreateSecretWithExpiration(string projectId = "my-project", string secretId = "my-secret-with-expiry")
+    {
+        // Calculate expiration time (1 hour from now)
+        DateTime expireTime = DateTime.UtcNow.AddHours(1);
+
+        // Create the client.
+        SecretManagerServiceClient client = SecretManagerServiceClient.Create();
+
+        // Build the parent resource name.
+        ProjectName projectName = new ProjectName(projectId);
+
+        // Convert DateTime to Timestamp
+        Timestamp timestamp = Timestamp.FromDateTime(expireTime);
+
+        // Build the secret with automatic replication and expiration time.
+        Secret secret = new Secret
+        {
+            Replication = new Replication
+            {
+                Automatic = new Replication.Types.Automatic(),
+            },
+            ExpireTime = timestamp
+        };
+
+        // Call the API.
+        Secret createdSecret = client.CreateSecret(projectName, secretId, secret);
+
+        Console.WriteLine($"Created secret {createdSecret.SecretName} with expiration time {expireTime}");
+        return createdSecret;
+    }
+}
+// [END secretmanager_create_secret_with_expiration]
diff --git a/secretmanager/api/SecretManager.Samples/DeleteRegionalSecretAnnotation.cs b/secretmanager/api/SecretManager.Samples/DeleteRegionalSecretAnnotation.cs
new file mode 100644
index 00000000000..6cca53a2f8f
--- /dev/null
+++ b/secretmanager/api/SecretManager.Samples/DeleteRegionalSecretAnnotation.cs
@@ -0,0 +1,56 @@
+/*
+ * Copyright 2026 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// [START secretmanager_delete_regional_secret_annotation]
+
+using Google.Cloud.SecretManager.V1;
+using Google.Protobuf.WellKnownTypes;
+using System;
+
+public class DeleteRegionalSecretAnnotationSample
+{
+    public Secret DeleteRegionalSecretAnnotation(
+        string projectId = "my-project",
+        string locationId = "my-location",
+        string secretId = "my-secret")
+    {
+        // Create the Regional Secret Manager Client.
+        SecretManagerServiceClient client = new SecretManagerServiceClientBuilder
+        {
+            Endpoint = $"secretmanager.{locationId}.rep.googleapis.com"
+        }.Build();
+
+        // Build the resource name of the secret.
+        SecretName secretName = SecretName.FromProjectLocationSecret(projectId, locationId, secretId);
+
+        // Get the secret.
+        Secret secret = client.GetSecret(secretName);
+
+        // Delete the annotation
+        secret.Annotations.Clear();
+
+        // Build the field mask.
+        FieldMask updateMask = FieldMask.FromString("annotations");
+
+        // Update the secret.
+        Secret updatedSecret = client.UpdateSecret(secret, updateMask);
+
+        // Print the new secret name.
+        Console.WriteLine($"Updated secret: {updatedSecret.Name}");
+        return updatedSecret;
+    }
+}
+// [END secretmanager_delete_regional_secret_annotation]
diff --git a/secretmanager/api/SecretManager.Samples/DeleteRegionalSecretExpiration.cs b/secretmanager/api/SecretManager.Samples/DeleteRegionalSecretExpiration.cs
new file mode 100644
index 00000000000..2840f865e49
--- /dev/null
+++ b/secretmanager/api/SecretManager.Samples/DeleteRegionalSecretExpiration.cs
@@ -0,0 +1,55 @@
+/*
+ * Copyright 2026 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// [START secretmanager_delete_regional_secret_expiration]
+
+using Google.Cloud.SecretManager.V1;
+using Google.Protobuf.WellKnownTypes;
+using System;
+
+public class DeleteRegionalSecretExpirationSample
+{
+    public Secret DeleteRegionalSecretExpiration(
+        string projectId = "my-project",
+        string secretId = "my-secret",
+        string locationId = "us-central1")
+    {
+        // Create the Regional Secret Manager Client.
+        SecretManagerServiceClient client = new SecretManagerServiceClientBuilder
+        {
+            Endpoint = $"secretmanager.{locationId}.rep.googleapis.com"
+        }.Build();
+
+        // Build the secret name
+        SecretName secretName = SecretName.FromProjectLocationSecret(projectId, locationId, secretId);
+
+        // Build the secret with no ExpireTime set (which will clear it)
+        Secret secret = new Secret
+        {
+            SecretName = secretName,
+        };
+
+        // Build the field mask for the fields to update
+        FieldMask updateMask = new FieldMask { Paths = { "expire_time" } };
+
+        // Update the secret to remove the expiration time
+        Secret updatedSecret = client.UpdateSecret(secret, updateMask);
+
+        Console.WriteLine($"Removed expiration from secret {updatedSecret.SecretName}");
+        return updatedSecret;
+    }
+}
+// [END secretmanager_delete_regional_secret_expiration]
diff --git a/secretmanager/api/SecretManager.Samples/DeleteRegionalSecretLabel.cs b/secretmanager/api/SecretManager.Samples/DeleteRegionalSecretLabel.cs
new file mode 100644
index 00000000000..f9ec0746e8c
--- /dev/null
+++ b/secretmanager/api/SecretManager.Samples/DeleteRegionalSecretLabel.cs
@@ -0,0 +1,56 @@
+/*
+ * Copyright 2026 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// [START secretmanager_delete_regional_secret_label]
+
+using Google.Cloud.SecretManager.V1;
+using Google.Protobuf.WellKnownTypes;
+using System;
+
+public class DeleteRegionalSecretLabelSample
+{
+    public Secret DeleteRegionalSecretLabel(
+        string projectId = "my-project",
+        string locationId = "my-location",
+        string secretId = "my-secret")
+    {
+        // Create the Regional Secret Manager Client.
+        SecretManagerServiceClient client = new SecretManagerServiceClientBuilder
+        {
+            Endpoint = $"secretmanager.{locationId}.rep.googleapis.com"
+        }.Build();
+
+        // Build the resource name of the secret.
+        SecretName secretName = SecretName.FromProjectLocationSecret(projectId, locationId, secretId);
+
+        // Get the secret.
+        Secret secret = client.GetSecret(secretName);
+
+        // Clear all labels
+        secret.Labels.Clear();
+
+        // Build the field mask.
+        FieldMask updateMask = FieldMask.FromString("labels");
+
+        // Update the secret.
+        Secret updatedSecret = client.UpdateSecret(secret, updateMask);
+
+        // Print the new secret name.
+        Console.WriteLine($"Updated secret: {updatedSecret.Name}");
+        return updatedSecret;
+    }
+}
+// [END secretmanager_delete_regional_secret_label]
diff --git a/secretmanager/api/SecretManager.Samples/DeleteSecretAnnotation.cs b/secretmanager/api/SecretManager.Samples/DeleteSecretAnnotation.cs
new file mode 100644
index 00000000000..778f32b2c3c
--- /dev/null
+++ b/secretmanager/api/SecretManager.Samples/DeleteSecretAnnotation.cs
@@ -0,0 +1,51 @@
+/*
+ * Copyright 2026 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// [START secretmanager_delete_secret_annotation]
+
+using Google.Cloud.SecretManager.V1;
+using Google.Protobuf.WellKnownTypes;
+using System;
+
+public class DeleteSecretAnnotationSample
+{
+    public Secret DeleteSecretAnnotation(
+      string projectId = "my-project", string secretId = "my-secret")
+    {
+        // Create the client.
+        SecretManagerServiceClient client = SecretManagerServiceClient.Create();
+
+        // Build the resource name of the secret.
+        SecretName secretName = new SecretName(projectId, secretId);
+
+        // Get the secret.
+        Secret secret = client.GetSecret(secretName);
+
+        // Clear all annotations
+        secret.Annotations.Clear();
+
+        // Build the field mask.
+        FieldMask updateMask = FieldMask.FromString("annotations");
+
+        // Update the secret.
+        Secret updatedSecret = client.UpdateSecret(secret, updateMask);
+
+        // Print the new secret name.
+        Console.WriteLine($"Updated secret: {updatedSecret.Name}");
+        return updatedSecret;
+    }
+}
+// [END secretmanager_delete_secret_annotation]
diff --git a/secretmanager/api/SecretManager.Samples/DeleteSecretExpiration.cs b/secretmanager/api/SecretManager.Samples/DeleteSecretExpiration.cs
new file mode 100644
index 00000000000..7a47c90e80c
--- /dev/null
+++ b/secretmanager/api/SecretManager.Samples/DeleteSecretExpiration.cs
@@ -0,0 +1,50 @@
+/*
+ * Copyright 2026 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// [START secretmanager_delete_secret_expiration]
+
+using Google.Cloud.SecretManager.V1;
+using Google.Protobuf.WellKnownTypes;
+using System;
+
+public class DeleteSecretExpirationSample
+{
+    public Secret DeleteSecretExpiration(string projectId = "my-project", string secretId = "my-secret-with-expiration")
+    {
+        // Create the client.
+        SecretManagerServiceClient client = SecretManagerServiceClient.Create();
+
+        // Build the resource name of the secret.
+        SecretName secretName = new SecretName(projectId, secretId);
+
+        // Create the secret with the expire_time field explicitly set to null
+        Secret secret = new Secret
+        {
+            SecretName = secretName,
+            // ExpireTime is not set, which will clear it
+        };
+
+        // Create the update mask for the fields to update
+        FieldMask updateMask = new FieldMask { Paths = { "expire_time" } };
+
+        // Update the secret
+        Secret updatedSecret = client.UpdateSecret(secret, updateMask);
+
+        Console.WriteLine($"Removed expiration from secret {updatedSecret.SecretName}");
+        return updatedSecret;
+    }
+}
+// [END secretmanager_delete_secret_expiration]
diff --git a/secretmanager/api/SecretManager.Samples/DeleteSecretLabel.cs b/secretmanager/api/SecretManager.Samples/DeleteSecretLabel.cs
new file mode 100644
index 00000000000..1be1d78d131
--- /dev/null
+++ b/secretmanager/api/SecretManager.Samples/DeleteSecretLabel.cs
@@ -0,0 +1,51 @@
+/*
+ * Copyright 2026 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// [START secretmanager_delete_secret_label]
+
+using Google.Cloud.SecretManager.V1;
+using Google.Protobuf.WellKnownTypes;
+using System;
+
+public class DeleteSecretLabelSample
+{
+    public Secret DeleteSecretLabel(
+      string projectId = "my-project", string secretId = "my-secret")
+    {
+        // Create the client.
+        SecretManagerServiceClient client = SecretManagerServiceClient.Create();
+
+        // Build the resource name of the secret.
+        SecretName secretName = new SecretName(projectId, secretId);
+
+        // Get the secret.
+        Secret secret = client.GetSecret(secretName);
+
+        // Clear all labels
+        secret.Labels.Clear();
+
+        // Build the field mask.
+        FieldMask updateMask = FieldMask.FromString("labels");
+
+        // Update the secret.
+        Secret updatedSecret = client.UpdateSecret(secret, updateMask);
+
+        // Print the new secret name.
+        Console.WriteLine($"Updated secret: {updatedSecret.Name}");
+        return updatedSecret;
+    }
+}
+// [END secretmanager_delete_secret_label]
diff --git a/secretmanager/api/SecretManager.Samples/EditSecretLabel.cs b/secretmanager/api/SecretManager.Samples/EditSecretLabel.cs
new file mode 100644
index 00000000000..71f73db0677
--- /dev/null
+++ b/secretmanager/api/SecretManager.Samples/EditSecretLabel.cs
@@ -0,0 +1,54 @@
+/*
+ * Copyright 2026 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// [START secretmanager_edit_secret_label]
+
+using Google.Cloud.SecretManager.V1;
+using Google.Protobuf.WellKnownTypes;
+using System;
+using System.Collections.Generic;
+
+public class EditSecretLabelSample
+{
+    public Secret EditSecretLabel(
+        string projectId = "my-project", string secretId = "my-secret")
+    {
+        string labelKey = "my-label-key";
+        string labelValue = "my-label-value";
+        // Create the Secret Manager client.
+        SecretManagerServiceClient client = SecretManagerServiceClient.Create();
+
+        // Build the resource name of the secret.
+        SecretName name = new SecretName(projectId, secretId);
+
+        // Get the secret.
+        Secret secret = client.GetSecret(name);
+
+        // Update the labels
+        secret.Labels[labelKey] = labelValue;
+
+        // Update the secret.
+        FieldMask updateMask = FieldMask.FromString("labels");
+
+        // Call the API.
+        Secret updatedSecret = client.UpdateSecret(secret, updateMask);
+
+        // Print the new secret name.
+        Console.WriteLine($"Updated secret: {updatedSecret.Name}");
+        return updatedSecret;
+    }
+}
+// [END secretmanager_edit_secret_label]
diff --git a/secretmanager/api/SecretManager.Samples/ListSecretVersionsWithFilter.cs b/secretmanager/api/SecretManager.Samples/ListSecretVersionsWithFilter.cs
new file mode 100644
index 00000000000..9468d3af6ab
--- /dev/null
+++ b/secretmanager/api/SecretManager.Samples/ListSecretVersionsWithFilter.cs
@@ -0,0 +1,54 @@
+/*
+ * Copyright 2026 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// [START secretmanager_list_secret_versions_with_filter]
+
+using Google.Cloud.SecretManager.V1;
+using System;
+using System.Collections.Generic;
+
+public class ListSecretVersionsWithFilterSample
+{
+    public IList<SecretVersion> ListSecretVersionsWithFilter(
+        string projectId = "my-project",
+        string secretId = "my-secret"
+        )
+    {
+        string filterStr = "state:DISABLED";
+        // Create the Secret Manager client.
+        SecretManagerServiceClient client = SecretManagerServiceClient.Create();
+
+        // Build the resource name of the parent secret.
+        SecretName secretName = new SecretName(projectId, secretId);
+
+        // Create the request with filter.
+        ListSecretVersionsRequest request = new ListSecretVersionsRequest
+        {
+            ParentAsSecretName = secretName,
+            Filter = filterStr
+        };
+
+        List<SecretVersion> secretVersions = new List<SecretVersion>();
+        // List all secret versions with the provided filter.
+        foreach (SecretVersion version in client.ListSecretVersions(request))
+        {
+            Console.WriteLine($"Found secret version: {version.Name}");
+            secretVersions.Add(version);
+        }
+        return secretVersions;
+    }
+}
+// [END secretmanager_list_secret_versions_with_filter]
diff --git a/secretmanager/api/SecretManager.Samples/ListSecretsWithFilter.cs b/secretmanager/api/SecretManager.Samples/ListSecretsWithFilter.cs
new file mode 100644
index 00000000000..c4e4274cef4
--- /dev/null
+++ b/secretmanager/api/SecretManager.Samples/ListSecretsWithFilter.cs
@@ -0,0 +1,53 @@
+/*
+ * Copyright 2026 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// [START secretmanager_list_secrets_with_filter]
+
+using Google.Api.Gax.ResourceNames;
+using Google.Cloud.SecretManager.V1;
+using System;
+using System.Collections.Generic;
+
+public class ListSecretsWithFilterSample
+{
+    public IList<Secret> ListSecretsWithFilter(string projectId = "my-project")
+    {
+        string filterStr = "labels.my-label-key=my-label-value";
+        // Create the Secret Manager client.
+        SecretManagerServiceClient client = SecretManagerServiceClient.Create();
+
+        // Build the resource name of the parent project.
+        ProjectName projectName = new ProjectName(projectId);
+        ListSecretsRequest request = new ListSecretsRequest
+        {
+            ParentAsProjectName = projectName,
+            Filter = filterStr
+        };
+
+        // Create a list to hold the secrets
+        List<Secret> secrets = new List<Secret>();
+
+        // List all secrets with the provided filter.
+        foreach (Secret secret in client.ListSecrets(request))
+        {
+            Console.WriteLine($"Found secret: {secret.Name}");
+            secrets.Add(secret);
+        }
+
+        return secrets;
+    }
+}
+// [END secretmanager_list_secrets_with_filter]
diff --git a/secretmanager/api/SecretManager.Samples/UpdateRegionalSecretExpiration.cs b/secretmanager/api/SecretManager.Samples/UpdateRegionalSecretExpiration.cs
new file mode 100644
index 00000000000..71afada1fc4
--- /dev/null
+++ b/secretmanager/api/SecretManager.Samples/UpdateRegionalSecretExpiration.cs
@@ -0,0 +1,62 @@
+/*
+ * Copyright 2026 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// [START secretmanager_update_regional_secret_expiration]
+
+using Google.Cloud.SecretManager.V1;
+using Google.Protobuf.WellKnownTypes;
+using System;
+
+public class UpdateRegionalSecretExpirationSample
+{
+    public Secret UpdateRegionalSecretExpiration(
+        string projectId = "my-project",
+        string secretId = "my-secret",
+        string locationId = "us-central1")
+    {
+        // Set new expiration time to 2 hours from now
+        DateTime newExpireTime = DateTime.UtcNow.AddHours(2);
+
+        // Create the Regional Secret Manager Client.
+        SecretManagerServiceClient client = new SecretManagerServiceClientBuilder
+        {
+            Endpoint = $"secretmanager.{locationId}.rep.googleapis.com"
+        }.Build();
+
+        // Build the secret name
+        SecretName secretName = SecretName.FromProjectLocationSecret(projectId, locationId, secretId);
+
+        // Convert DateTime to Timestamp
+        Timestamp timestamp = Timestamp.FromDateTime(newExpireTime);
+
+        // Build the secret with the new expiration time
+        Secret secret = new Secret
+        {
+            SecretName = secretName,
+            ExpireTime = timestamp
+        };
+
+        // Build the field mask for the fields to update
+        FieldMask updateMask = new FieldMask { Paths = { "expire_time" } };
+
+        // Update the secret
+        Secret updatedSecret = client.UpdateSecret(secret, updateMask);
+
+        Console.WriteLine($"Updated secret {updatedSecret.SecretName} expiration time to {newExpireTime}");
+        return updatedSecret;
+    }
+}
+// [END secretmanager_update_regional_secret_expiration]
diff --git a/secretmanager/api/SecretManager.Samples/UpdateSecretExpiration.cs b/secretmanager/api/SecretManager.Samples/UpdateSecretExpiration.cs
new file mode 100644
index 00000000000..0b80912e5ad
--- /dev/null
+++ b/secretmanager/api/SecretManager.Samples/UpdateSecretExpiration.cs
@@ -0,0 +1,56 @@
+/*
+ * Copyright 2026 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// [START secretmanager_update_secret_expiration]
+
+using Google.Cloud.SecretManager.V1;
+using Google.Protobuf.WellKnownTypes;
+using System;
+
+public class UpdateSecretExpirationSample
+{
+    public Secret UpdateSecretExpiration(string projectId = "my-project", string secretId = "my-secret-with-expiration")
+    {
+        // Calculate new expiration time (2 hours from now)
+        DateTime newExpireTime = DateTime.UtcNow.AddHours(2);
+
+        // Create the client.
+        SecretManagerServiceClient client = SecretManagerServiceClient.Create();
+
+        // Build the resource name of the secret.
+        SecretName secretName = new SecretName(projectId, secretId);
+
+        // Convert DateTime to Timestamp
+        Timestamp timestamp = Timestamp.FromDateTime(newExpireTime);
+
+        // Create the secret to update with the new expiration time
+        Secret secret = new Secret
+        {
+            SecretName = secretName,
+            ExpireTime = timestamp
+        };
+
+        // Create the update mask for the fields to update
+        FieldMask updateMask = new FieldMask { Paths = { "expire_time" } };
+
+        // Update the secret
+        Secret updatedSecret = client.UpdateSecret(secret, updateMask);
+
+        Console.WriteLine($"Updated secret {updatedSecret.SecretName} expiration time to {newExpireTime}");
+        return updatedSecret;
+    }
+}
+// [END secretmanager_update_secret_expiration]
diff --git a/secretmanager/api/SecretManager.Samples/createRegionalSecretWithCmek.cs b/secretmanager/api/SecretManager.Samples/createRegionalSecretWithCmek.cs
new file mode 100644
index 00000000000..5be2e2541d4
--- /dev/null
+++ b/secretmanager/api/SecretManager.Samples/createRegionalSecretWithCmek.cs
@@ -0,0 +1,57 @@
+/*
+ * Copyright 2026 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// [START secretmanager_create_regional_secret_with_cmek]
+
+using Google.Api.Gax.ResourceNames;
+using Google.Cloud.SecretManager.V1;
+using System;
+
+public class CreateRegionalSecretWithCmekSample
+{
+    public Secret CreateRegionalSecretWithCmek(
+        string projectId = "my-project",
+        string locationId = "us-central1",
+        string secretId = "my-secret",
+        string kmsKeyName = "projects/my-project/locations/us-central1/keyRings/my-keyring/cryptoKeys/my-key")
+    {
+        // Create the Regional Secret Manager Client.
+        SecretManagerServiceClient client = new SecretManagerServiceClientBuilder
+        {
+            Endpoint = $"secretmanager.{locationId}.rep.googleapis.com"
+        }.Build();
+
+        // Build the parent resource name.
+        LocationName location = new LocationName(projectId, locationId);
+
+        // Build the secret with CMEK.
+        Secret secret = new Secret
+        {
+            CustomerManagedEncryption = new CustomerManagedEncryption
+            {
+                KmsKeyName = kmsKeyName
+            }
+        };
+
+        // Call the API.
+        Secret createdSecret = client.CreateSecret(location, secretId, secret);
+
+        // Print information about the created secret.
+        Console.WriteLine($"Created secret {createdSecret.Name} with CMEK key {kmsKeyName}");
+        return createdSecret;
+    }
+}
+// [END secretmanager_create_regional_secret_with_cmek]
diff --git a/secretmanager/api/SecretManager.Samples/createSecretWithCmek.cs b/secretmanager/api/SecretManager.Samples/createSecretWithCmek.cs
new file mode 100644
index 00000000000..882e7687f99
--- /dev/null
+++ b/secretmanager/api/SecretManager.Samples/createSecretWithCmek.cs
@@ -0,0 +1,59 @@
+/*
+ * Copyright 2026 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// [START secretmanager_create_secret_with_cmek]
+
+using Google.Api.Gax.ResourceNames;
+using Google.Cloud.SecretManager.V1;
+using System;
+
+public class CreateSecretWithCmekSample
+{
+    public Secret CreateSecretWithCmek(
+        string projectId = "my-project",
+        string secretId = "my-secret",
+        string kmsKeyName = "projects/my-project/locations/global/keyRings/my-keyring/cryptoKeys/my-key")
+    {
+        // Create the client.
+        SecretManagerServiceClient client = SecretManagerServiceClient.Create();
+
+        // Build the parent resource name.
+        ProjectName projectName = new ProjectName(projectId);
+
+        // Build the secret with automatic replication and CMEK.
+        Secret secret = new Secret
+        {
+            Replication = new Replication
+            {
+                Automatic = new Replication.Types.Automatic
+                {
+                    CustomerManagedEncryption = new CustomerManagedEncryption
+                    {
+                        KmsKeyName = kmsKeyName
+                    }
+                }
+            }
+        };
+
+        // Call the API.
+        Secret createdSecret = client.CreateSecret(projectName, secretId, secret);
+
+        // Print information about the created secret.
+        Console.WriteLine($"Created secret {createdSecret.Name} with CMEK key {kmsKeyName}");
+        return createdSecret;
+    }
+}
+// [END secretmanager_create_secret_with_cmek]