diff --git a/bff/src/Bff.Blazor.Client/Internals/ClaimRecord.cs b/bff/src/Bff.Blazor.Client/Internals/ClaimRecord.cs
index 6f597bfed..8b9046761 100644
--- a/bff/src/Bff.Blazor.Client/Internals/ClaimRecord.cs
+++ b/bff/src/Bff.Blazor.Client/Internals/ClaimRecord.cs
@@ -3,7 +3,7 @@
 
 using System.Text.Json.Serialization;
 
-namespace Duende.Bff.Blazor.Client;
+namespace Duende.Bff.Blazor.Client.Internals;
 
 /// <summary>
 /// Serialization friendly claim.
@@ -28,13 +28,13 @@ internal class ClaimRecord()
     /// The type
     /// </summary>
     [JsonPropertyName("type")]
-    public string Type { get; init; } = default!;
+    public string Type { get; init; } = string.Empty;
 
     /// <summary>
     /// The value
     /// </summary>
     [JsonPropertyName("value")]
-    public object Value { get; init; } = default!;
+    public object Value { get; init; } = string.Empty;
 
     /// <summary>
     /// The value type
diff --git a/bff/src/Bff.Blazor.Client/Internals/ClaimRecordExtensions.cs b/bff/src/Bff.Blazor.Client/Internals/ClaimRecordExtensions.cs
index 728df3986..2c5d2fe97 100644
--- a/bff/src/Bff.Blazor.Client/Internals/ClaimRecordExtensions.cs
+++ b/bff/src/Bff.Blazor.Client/Internals/ClaimRecordExtensions.cs
@@ -2,9 +2,8 @@
 // See LICENSE in the project root for license information.
 
 using System.Security.Claims;
-using Duende.Bff.Blazor.Client;
 
-namespace Duende.Bff.Internal;
+namespace Duende.Bff.Blazor.Client.Internals;
 
 internal static class ClaimRecordExtensions
 {
@@ -13,8 +12,13 @@ internal static class ClaimRecordExtensions
     /// </summary>
     public static ClaimsPrincipal ToClaimsPrincipal(this ClaimsPrincipalRecord principal)
     {
-        var claims = principal.Claims.Select(x => new Claim(x.Type, x.Value.ToString() ?? string.Empty, x.ValueType ?? ClaimValueTypes.String))
-            .ToArray();
+        // ReSharper disable once ConditionIsAlwaysTrueOrFalseAccordingToNullableAPIContract
+        var claims = principal.Claims is null
+            ? []
+            // ReSharper disable once ConditionalAccessQualifierIsNonNullableAccordingToAPIContract
+            // ReSharper disable once NullCoalescingConditionIsAlwaysNotNullAccordingToAPIContract
+            : principal.Claims.Select(x => new Claim(x.Type ?? string.Empty, x.Value?.ToString() ?? string.Empty, x.ValueType ?? ClaimValueTypes.String)).ToArray();
+
         var id = new ClaimsIdentity(claims, principal.AuthenticationType, principal.NameClaimType,
             principal.RoleClaimType);
 
diff --git a/bff/src/Bff.Blazor.Client/Internals/ClaimsPrincipalRecord.cs b/bff/src/Bff.Blazor.Client/Internals/ClaimsPrincipalRecord.cs
index e5e4ea355..e24a00be7 100644
--- a/bff/src/Bff.Blazor.Client/Internals/ClaimsPrincipalRecord.cs
+++ b/bff/src/Bff.Blazor.Client/Internals/ClaimsPrincipalRecord.cs
@@ -1,9 +1,7 @@
 // Copyright (c) Duende Software. All rights reserved.
 // See LICENSE in the project root for license information.
 
-using Duende.Bff.Blazor.Client;
-
-namespace Duende.Bff.Internal;
+namespace Duende.Bff.Blazor.Client.Internals;
 
 /// <summary>
 /// Serialization friendly ClaimsPrincipal
@@ -28,5 +26,5 @@ internal class ClaimsPrincipalRecord
     /// <summary>
     /// The claims
     /// </summary>
-    public ClaimRecord[] Claims { get; init; } = default!;
+    public ClaimRecord[] Claims { get; init; } = [];
 }
diff --git a/bff/src/Bff.Blazor.Client/Internals/PersistentUserService.cs b/bff/src/Bff.Blazor.Client/Internals/PersistentUserService.cs
index 26af42470..870299680 100644
--- a/bff/src/Bff.Blazor.Client/Internals/PersistentUserService.cs
+++ b/bff/src/Bff.Blazor.Client/Internals/PersistentUserService.cs
@@ -3,7 +3,6 @@
 
 using System.Diagnostics.CodeAnalysis;
 using System.Security.Claims;
-using Duende.Bff.Internal;
 using Microsoft.AspNetCore.Components;
 using Microsoft.Extensions.Logging;
 
diff --git a/bff/src/Bff/Internal/ClaimRecord.cs b/bff/src/Bff/Internal/ClaimRecord.cs
index 2f9788503..321e12879 100644
--- a/bff/src/Bff/Internal/ClaimRecord.cs
+++ b/bff/src/Bff/Internal/ClaimRecord.cs
@@ -11,7 +11,7 @@ namespace Duende.Bff.Internal;
 internal class ClaimRecord()
 {
     /// <summary>
-    /// 
+    ///
     /// </summary>
     /// <param name="type"></param>
     /// <param name="value"></param>
@@ -25,13 +25,13 @@ internal class ClaimRecord()
     /// The type
     /// </summary>
     [JsonPropertyName("type")]
-    public string Type { get; init; } = default!;
+    public string Type { get; init; } = string.Empty;
 
     /// <summary>
     /// The value
     /// </summary>
     [JsonPropertyName("value")]
-    public object Value { get; init; } = default!;
+    public object Value { get; init; } = string.Empty;
 
     /// <summary>
     /// The value type
diff --git a/bff/src/Bff/Internal/ClaimRecordExtensions.cs b/bff/src/Bff/Internal/ClaimRecordExtensions.cs
index cbe959a00..f6feb506c 100644
--- a/bff/src/Bff/Internal/ClaimRecordExtensions.cs
+++ b/bff/src/Bff/Internal/ClaimRecordExtensions.cs
@@ -12,8 +12,13 @@ internal static class ClaimRecordExtensions
     /// </summary>
     public static ClaimsPrincipal ToClaimsPrincipal(this ClaimsPrincipalRecord principal)
     {
-        var claims = principal.Claims.Select(x => new Claim(x.Type, x.Value.ToString() ?? string.Empty, x.ValueType ?? ClaimValueTypes.String))
-            .ToArray();
+        // ReSharper disable once ConditionIsAlwaysTrueOrFalseAccordingToNullableAPIContract
+        var claims = principal.Claims is null
+            ? []
+            // ReSharper disable once ConditionalAccessQualifierIsNonNullableAccordingToAPIContract
+            // ReSharper disable once NullCoalescingConditionIsAlwaysNotNullAccordingToAPIContract
+            : principal.Claims.Select(x => new Claim(x.Type ?? string.Empty, x.Value?.ToString() ?? string.Empty, x.ValueType ?? ClaimValueTypes.String)).ToArray();
+
         var id = new ClaimsIdentity(claims, principal.AuthenticationType, principal.NameClaimType,
             principal.RoleClaimType);
 
diff --git a/bff/src/Bff/Internal/ClaimsPrincipalRecord.cs b/bff/src/Bff/Internal/ClaimsPrincipalRecord.cs
index c97d1cb13..6f68693a0 100644
--- a/bff/src/Bff/Internal/ClaimsPrincipalRecord.cs
+++ b/bff/src/Bff/Internal/ClaimsPrincipalRecord.cs
@@ -26,5 +26,5 @@ internal class ClaimsPrincipalRecord
     /// <summary>
     /// The claims
     /// </summary>
-    public ClaimRecord[] Claims { get; init; } = default!;
+    public ClaimRecord[] Claims { get; init; } = [];
 }
diff --git a/bff/test/Bff.Tests/Internal/ClaimsPrincipalRecordTests.cs b/bff/test/Bff.Tests/Internal/ClaimsPrincipalRecordTests.cs
new file mode 100644
index 000000000..3d1916546
--- /dev/null
+++ b/bff/test/Bff.Tests/Internal/ClaimsPrincipalRecordTests.cs
@@ -0,0 +1,89 @@
+// Copyright (c) Duende Software. All rights reserved.
+// See LICENSE in the project root for license information.
+
+using System.Security.Claims;
+using System.Text.Json;
+using Duende.Bff.Internal;
+
+namespace Duende.Bff.Tests.Internal;
+
+public class ClaimsPrincipalRecordTests
+{
+    [Fact]
+    public void Can_convert_between_ClaimsPrincipal_and_ClaimsPrincipalRecord()
+    {
+        var original = new ClaimsPrincipal(new ClaimsIdentity(new[]
+        {
+            new Claim("sub", "123"),
+            new Claim("name", "Alice"),
+            new Claim("role", "admin")
+        }, "TestAuthType", "name", "role"));
+
+        var record = original.ToClaimsPrincipalLite();
+        var reconstructed = record.ToClaimsPrincipal();
+
+        reconstructed.Identity!.AuthenticationType.ShouldBe(original.Identity!.AuthenticationType);
+        reconstructed.Identity!.Name.ShouldBe(original.Identity!.Name);
+
+        var originalClaims = original.Claims.ToDictionary(c => c.Type, c => c.Value);
+        var reconstructedClaims = reconstructed.Claims.ToDictionary(c => c.Type, c => c.Value);
+
+        originalClaims.Count.ShouldBe(reconstructedClaims.Count);
+        foreach (var kvp in originalClaims)
+        {
+            reconstructedClaims.ShouldContainKey(kvp.Key);
+            reconstructedClaims[kvp.Key].ShouldBe(kvp.Value);
+        }
+    }
+
+    [Fact]
+    public void Can_convert_default_ClaimsPrincipalRecord()
+    {
+        var original = new ClaimsPrincipalRecord();
+
+        Should.NotThrow(() => original.ToClaimsPrincipal());
+    }
+
+    [Fact]
+    public void Can_convert_ClaimsPrincipalRecord_with_default_ClaimsRecord()
+    {
+        var original = new ClaimsPrincipalRecord
+        {
+            Claims =
+            [
+                new ClaimRecord()
+            ]
+        };
+
+        Should.NotThrow(() => original.ToClaimsPrincipal());
+    }
+
+    [Fact]
+    public void ToClaimsPrincipal_handles_null_Claims_from_deserialization()
+    {
+        var serializedClaimsPrincipal = """{"Claims": null}""";
+        var record = JsonSerializer.Deserialize<ClaimsPrincipalRecord>(serializedClaimsPrincipal);
+
+        Should.NotThrow(() => record!.ToClaimsPrincipal());
+    }
+
+    [Fact]
+    public void ToClaimsPrincipal_handles_null_Type_in_ClaimRecord_from_deserialization()
+    {
+        var serializedClaimsPrincipal = """{"Claims": [{"type": null, "value": "test"}]}""";
+        var record = JsonSerializer.Deserialize<ClaimsPrincipalRecord>(serializedClaimsPrincipal);
+
+        var principal = record!.ToClaimsPrincipal();
+        principal.Claims.Single().Type.ShouldBe(string.Empty);
+    }
+
+    [Fact]
+    public void ToClaimsPrincipal_handles_null_Value_in_ClaimRecord_from_deserialization()
+    {
+        var serializedClaimsPrincipal = """{"Claims": [{"type": "sub", "value": null}]}""";
+        var record = JsonSerializer.Deserialize<ClaimsPrincipalRecord>(serializedClaimsPrincipal);
+
+        var principal = record!.ToClaimsPrincipal();
+        principal.Claims.Single().Value.ShouldBe(string.Empty);
+    }
+}