diff --git a/src/Altinn.App.Clients.Fiks/Constants/FiksArkivConstants.cs b/src/Altinn.App.Clients.Fiks/Constants/FiksArkivConstants.cs
index 3026c63d71..f1e330a834 100644
--- a/src/Altinn.App.Clients.Fiks/Constants/FiksArkivConstants.cs
+++ b/src/Altinn.App.Clients.Fiks/Constants/FiksArkivConstants.cs
@@ -1,3 +1,5 @@
+using Altinn.App.Clients.Fiks.FiksArkiv.Models;
+using KS.Fiks.Arkiv.Models.V1.Kodelister;
 using KS.Fiks.Arkiv.Models.V1.Meldingstyper;
 
 namespace Altinn.App.Clients.Fiks.Constants;
@@ -37,11 +39,16 @@ public static class MessageTypes
         public const string ArchiveRecordCreationReceipt = FiksArkivMeldingtype.ArkivmeldingOpprettKvittering;
     }
 
+    /// <summary>
+    /// Classification IDs for Fiks Arkiv messages.
+    /// </summary>
+    /// <remarks>Callers can also specify their own, additional, classifications via
+    /// <see cref="FiksArkivMetadataSettings.CaseFileClassifications"/>.</remarks>
     internal static class ClassificationId
     {
-        public const string NationalIdentityNumber = "Fødselsnummer";
-        public const string OrganizationNumber = "Organisasjonsnummer";
+        public static readonly string NationalIdentityNumber = KlassifikasjonstypeKoder.Foedselsnummer.Verdi;
+        public const string OrganizationNumber = "ORGNR";
         public const string AltinnUserId = "AltinnBrukerId";
-        public const string SystemUserId = "SystembrukerId";
+        public const string SystemUserId = "AltinnSystembrukerId";
     }
 }
diff --git a/src/Altinn.App.Clients.Fiks/Extensions/FiksArkivClassificationExtensions.cs b/src/Altinn.App.Clients.Fiks/Extensions/FiksArkivClassificationExtensions.cs
new file mode 100644
index 0000000000..5e4d5f56d1
--- /dev/null
+++ b/src/Altinn.App.Clients.Fiks/Extensions/FiksArkivClassificationExtensions.cs
@@ -0,0 +1,16 @@
+using Altinn.App.Clients.Fiks.FiksArkiv.Models;
+using KS.Fiks.Arkiv.Models.V1.Arkivering.Arkivmelding;
+
+namespace Altinn.App.Clients.Fiks.Extensions;
+
+internal static class FiksArkivClassificationExtensions
+{
+    public static Klassifikasjon ToKlassifikasjon(this FiksArkivClassification classification) =>
+        new()
+        {
+            KlassifikasjonssystemID = classification.SystemId,
+            KlasseID = classification.ClassificationId,
+            Tittel = classification.Title,
+            ErSkjermet = classification.IsRestricted,
+        };
+}
diff --git a/src/Altinn.App.Clients.Fiks/Factories/KlassifikasjonFactory.cs b/src/Altinn.App.Clients.Fiks/Factories/KlassifikasjonFactory.cs
index 525a61c851..b2bda3f491 100644
--- a/src/Altinn.App.Clients.Fiks/Factories/KlassifikasjonFactory.cs
+++ b/src/Altinn.App.Clients.Fiks/Factories/KlassifikasjonFactory.cs
@@ -25,6 +25,7 @@ public static async Task<Klassifikasjon> CreateUser(Authenticated.User user)
                     .Party.SSN.ToString(CultureInfo.InvariantCulture)
                     .EnsureNotNullOrEmpty("Classification.Id"),
                 Tittel = userProfile.Party.Name.EnsureNotEmpty("Classification.Title"),
+                ErSkjermet = true,
             }
             : new Klassifikasjon
             {
diff --git a/src/Altinn.App.Clients.Fiks/FiksArkiv/FiksArkivConfigResolver.cs b/src/Altinn.App.Clients.Fiks/FiksArkiv/FiksArkivConfigResolver.cs
index 130aa626e5..434f34e82b 100644
--- a/src/Altinn.App.Clients.Fiks/FiksArkiv/FiksArkivConfigResolver.cs
+++ b/src/Altinn.App.Clients.Fiks/FiksArkiv/FiksArkivConfigResolver.cs
@@ -212,23 +212,16 @@ public Korrespondansepart GetRecipientParty(Instance instance, FiksArkivRecipien
         );
 
     /// <inheritdoc />
-    public async Task<Klassifikasjon> GetInstanceOwnerClassification(
+    public async Task<IReadOnlyList<Klassifikasjon>> GetCaseFileClassifications(
         Authenticated auth,
         CancellationToken cancellationToken = default
     )
     {
-        cancellationToken.ThrowIfCancellationRequested();
-
-        return auth switch
-        {
-            Authenticated.User user => await KlassifikasjonFactory.CreateUser(user), // Note: Doesn't accept cancellation token.. yet
-            Authenticated.SystemUser systemUser => KlassifikasjonFactory.CreateSystemUser(systemUser),
-            Authenticated.ServiceOwner serviceOwner => KlassifikasjonFactory.CreateServiceOwner(serviceOwner),
-            Authenticated.Org org => KlassifikasjonFactory.CreateOrganization(org),
-            _ => throw new FiksArkivException(
-                $"Could not determine submitter details from authentication context: {auth}"
-            ),
-        };
+        return
+        [
+            await GetInstanceOwnerClassification(auth, cancellationToken: cancellationToken),
+            .. _fiksArkivSettings.Metadata?.CaseFileClassifications?.Select(x => x.ToKlassifikasjon()) ?? [],
+        ];
     }
 
     /// <inheritdoc />
@@ -300,6 +293,25 @@ private async Task<LayoutEvaluatorState> GetLayoutState(Instance instance)
         return await _layoutStateInitializer.Init(unitOfWork, null);
     }
 
+    private static async Task<Klassifikasjon> GetInstanceOwnerClassification(
+        Authenticated auth,
+        CancellationToken cancellationToken = default
+    )
+    {
+        cancellationToken.ThrowIfCancellationRequested();
+
+        return auth switch
+        {
+            Authenticated.User user => await KlassifikasjonFactory.CreateUser(user), // Note: Doesn't accept cancellation token.. yet
+            Authenticated.SystemUser systemUser => KlassifikasjonFactory.CreateSystemUser(systemUser),
+            Authenticated.ServiceOwner serviceOwner => KlassifikasjonFactory.CreateServiceOwner(serviceOwner),
+            Authenticated.Org org => KlassifikasjonFactory.CreateOrganization(org),
+            _ => throw new FiksArkivException(
+                $"Could not determine submitter details from authentication context: {auth}"
+            ),
+        };
+    }
+
     private static async Task<T?> GetBindableConfigValue<T>(
         LayoutEvaluatorState layoutState,
         Instance instance,
diff --git a/src/Altinn.App.Clients.Fiks/FiksArkiv/FiksArkivDefaultPayloadGenerator.cs b/src/Altinn.App.Clients.Fiks/FiksArkiv/FiksArkivDefaultPayloadGenerator.cs
index 7cf2008fe1..ad28b0d5cf 100644
--- a/src/Altinn.App.Clients.Fiks/FiksArkiv/FiksArkivDefaultPayloadGenerator.cs
+++ b/src/Altinn.App.Clients.Fiks/FiksArkiv/FiksArkivDefaultPayloadGenerator.cs
@@ -14,7 +14,6 @@
 using KS.Fiks.Arkiv.Models.V1.Metadatakatalog;
 using Microsoft.Extensions.Hosting;
 using Microsoft.Extensions.Logging;
-using Microsoft.Extensions.Options;
 using Kode = KS.Fiks.Arkiv.Models.V1.Kodelister.Kode;
 
 namespace Altinn.App.Clients.Fiks.FiksArkiv;
@@ -27,7 +26,6 @@ internal sealed class FiksArkivDefaultPayloadGenerator : IFiksArkivPayloadGenera
     private readonly ILogger<FiksArkivDefaultPayloadGenerator> _logger;
     private readonly IHostEnvironment _hostEnvironment;
     private readonly IFiksArkivConfigResolver _fiksArkivConfigResolver;
-    private readonly FiksIOSettings _fiksIOSettings;
     private readonly TimeProvider _timeProvider;
 
     private bool _indentXmlSerialization => !_hostEnvironment.IsProduction();
@@ -39,7 +37,6 @@ public FiksArkivDefaultPayloadGenerator(
         ILogger<FiksArkivDefaultPayloadGenerator> logger,
         IHostEnvironment hostEnvironment,
         IFiksArkivConfigResolver fiksArkivConfigResolver,
-        IOptions<FiksIOSettings> fiksIOSettings,
         TimeProvider? timeProvider = null
     )
     {
@@ -49,7 +46,6 @@ public FiksArkivDefaultPayloadGenerator(
         _logger = logger;
         _hostEnvironment = hostEnvironment;
         _fiksArkivConfigResolver = fiksArkivConfigResolver;
-        _fiksIOSettings = fiksIOSettings.Value;
         _timeProvider = timeProvider ?? TimeProvider.System;
     }
 
@@ -67,6 +63,7 @@ public async Task<IEnumerable<FiksIOMessagePayload>> GeneratePayload(
                 $"Unsupported message type: {messageType}. {nameof(FiksArkivDefaultPayloadGenerator)} can only handle {FiksArkivConstants.MessageTypes.CreateArchiveRecord} requests."
             );
 
+        var now = _timeProvider.GetUtcNow();
         var appMetadata = await _appMetadata.GetApplicationMetadata();
         var documentCreator = appMetadata.AppIdentifier.Org;
         var archiveDocuments = await GetArchiveDocuments(instance, cancellationToken);
@@ -74,7 +71,7 @@ public async Task<IEnumerable<FiksIOMessagePayload>> GeneratePayload(
         var documentMetadata = await _fiksArkivConfigResolver.GetArchiveDocumentMetadata(instance, cancellationToken);
         var recipientParty = _fiksArkivConfigResolver.GetRecipientParty(instance, recipient);
         var instanceOwnerParty = await _fiksArkivConfigResolver.GetInstanceOwnerParty(instance, cancellationToken);
-        var instanceOwnerClassification = await _fiksArkivConfigResolver.GetInstanceOwnerClassification(
+        var caseFileClassifications = await _fiksArkivConfigResolver.GetCaseFileClassifications(
             _authenticationContext.Current,
             cancellationToken
         );
@@ -84,8 +81,8 @@ public async Task<IEnumerable<FiksIOMessagePayload>> GeneratePayload(
             Tittel = documentMetadata?.CaseFileTitle ?? defaultDocumentTitle,
             OffentligTittel = documentMetadata?.CaseFileTitle ?? defaultDocumentTitle,
             AdministrativEnhet = new AdministrativEnhet { Navn = documentCreator },
-            Saksaar = _timeProvider.GetLocalNow().Year,
-            Saksdato = _timeProvider.GetLocalNow().DateTime,
+            Saksaar = now.Year,
+            Saksdato = now.UtcDateTime,
             ReferanseEksternNoekkel = new EksternNoekkel
             {
                 Fagsystem = appMetadata.AppIdentifier.ToString(),
@@ -93,13 +90,16 @@ public async Task<IEnumerable<FiksIOMessagePayload>> GeneratePayload(
             },
         };
 
-        caseFile.Klassifikasjon.Add(instanceOwnerClassification);
+        foreach (var classification in caseFileClassifications)
+        {
+            caseFile.Klassifikasjon.Add(classification);
+        }
 
         var journalEntry = new Journalpost
         {
-            Journalaar = _timeProvider.GetLocalNow().Year,
-            DokumentetsDato = _timeProvider.GetLocalNow().DateTime,
-            SendtDato = _timeProvider.GetLocalNow().DateTime,
+            Journalaar = now.Year,
+            DokumentetsDato = now.UtcDateTime,
+            SendtDato = now.UtcDateTime,
             Tittel = documentMetadata?.JournalEntryTitle ?? defaultDocumentTitle,
             OffentligTittel = documentMetadata?.JournalEntryTitle ?? defaultDocumentTitle,
             OpprettetAv = documentCreator,
@@ -131,12 +131,12 @@ public async Task<IEnumerable<FiksIOMessagePayload>> GeneratePayload(
         }
 
         // Main form data file
-        journalEntry.Dokumentbeskrivelse.Add(GetDocumentDescription(archiveDocuments.PrimaryDocument));
+        journalEntry.Dokumentbeskrivelse.Add(GetDocumentDescription(archiveDocuments.PrimaryDocument, now));
 
         // Attachments
         foreach (var attachment in archiveDocuments.AttachmentDocuments)
         {
-            journalEntry.Dokumentbeskrivelse.Add(GetDocumentDescription(attachment));
+            journalEntry.Dokumentbeskrivelse.Add(GetDocumentDescription(attachment, now));
         }
 
         // Archive record
@@ -170,6 +170,7 @@ private async Task<FiksArkivDocuments> GetArchiveDocuments(
             primaryDataElement,
             primaryDocumentSettings.Filename,
             DokumenttypeKoder.Dokument,
+            primaryDocumentSettings.FormatCode,
             instanceId,
             cancellationToken
         );
@@ -191,6 +192,7 @@ await GetPayload(
                             x,
                             attachmentSetting.Filename,
                             DokumenttypeKoder.Vedlegg,
+                            attachmentSetting.FormatCode,
                             instanceId,
                             cancellationToken
                         )
@@ -206,6 +208,7 @@ private async Task<MessagePayloadWrapper> GetPayload(
         DataElement dataElement,
         string? filename,
         Kode fileTypeCode,
+        string? fileFormatCode,
         InstanceIdentifier instanceId,
         CancellationToken cancellationToken = default
     )
@@ -225,11 +228,12 @@ await _dataClient.GetDataBytes(
                     cancellationToken: cancellationToken
                 )
             ),
-            fileTypeCode
+            fileTypeCode,
+            fileFormatCode
         );
     }
 
-    private Dokumentbeskrivelse GetDocumentDescription(MessagePayloadWrapper payloadWrapper)
+    private static Dokumentbeskrivelse GetDocumentDescription(MessagePayloadWrapper payloadWrapper, DateTimeOffset now)
     {
         var documentClassification =
             payloadWrapper.FileTypeCode == DokumenttypeKoder.Dokument
@@ -254,24 +258,19 @@ private Dokumentbeskrivelse GetDocumentDescription(MessagePayloadWrapper payload
                 KodeProperty = documentClassification.Verdi,
                 Beskrivelse = documentClassification.Beskrivelse,
             },
-            OpprettetDato = _timeProvider.GetLocalNow().DateTime,
+            OpprettetDato = now.UtcDateTime,
         };
 
         metadata.Dokumentobjekt.Add(
             new Dokumentobjekt
             {
-                SystemID = new SystemID
-                {
-                    Value = _fiksIOSettings.AccountId.ToString(),
-                    Label = FiksArkivConstants.AltinnSystemId,
-                },
                 Filnavn = payloadWrapper.Payload.Filename,
                 ReferanseDokumentfil = payloadWrapper.Payload.Filename,
-                Format = new Format { KodeProperty = payloadWrapper.Payload.GetDotlessFileExtension() },
+                Format = payloadWrapper.GetFileFormat(),
                 Variantformat = new Variantformat
                 {
-                    KodeProperty = VariantformatKoder.Produksjonsformat.Verdi,
-                    Beskrivelse = VariantformatKoder.Produksjonsformat.Beskrivelse,
+                    KodeProperty = VariantformatKoder.Arkivformat.Verdi,
+                    Beskrivelse = VariantformatKoder.Arkivformat.Beskrivelse,
                 },
             }
         );
diff --git a/src/Altinn.App.Clients.Fiks/FiksArkiv/IFiksArkivConfigResolver.cs b/src/Altinn.App.Clients.Fiks/FiksArkiv/IFiksArkivConfigResolver.cs
index 406bcd7e1d..ab5bad2450 100644
--- a/src/Altinn.App.Clients.Fiks/FiksArkiv/IFiksArkivConfigResolver.cs
+++ b/src/Altinn.App.Clients.Fiks/FiksArkiv/IFiksArkivConfigResolver.cs
@@ -54,9 +54,11 @@ public interface IFiksArkivConfigResolver
     Task<Korrespondansepart?> GetInstanceOwnerParty(Instance instance, CancellationToken cancellationToken = default);
 
     /// <summary>
-    /// Gets the classification of the instance owner (klassifikasjon).
+    /// Gets the case file classifications (klassifikasjoner) for the shipment.
+    /// Always includes the instance owner classification derived from <paramref name="auth"/>, followed by any
+    /// classifications configured in <see cref="FiksArkivMetadataSettings.CaseFileClassifications"/>.
     /// </summary>
-    Task<Klassifikasjon> GetInstanceOwnerClassification(
+    Task<IReadOnlyList<Klassifikasjon>> GetCaseFileClassifications(
         Authenticated auth,
         CancellationToken cancellationToken = default
     );
diff --git a/src/Altinn.App.Clients.Fiks/FiksArkiv/Models/FiksArkivSettings.cs b/src/Altinn.App.Clients.Fiks/FiksArkiv/Models/FiksArkivSettings.cs
index ef05ded3e1..fc29a21ad9 100644
--- a/src/Altinn.App.Clients.Fiks/FiksArkiv/Models/FiksArkivSettings.cs
+++ b/src/Altinn.App.Clients.Fiks/FiksArkiv/Models/FiksArkivSettings.cs
@@ -122,6 +122,13 @@ public sealed record FiksArkivMetadataSettings
     [JsonPropertyName("caseFileTitle")]
     public FiksArkivBindableValue<string>? CaseFileTitle { get; set; }
 
+    /// <summary>
+    /// Optional classifications (klassifikasjon) to attach to the generated saksmappe (case file) element in the arkivmelding.xml.
+    /// These are appended in order after the implicit instance-owner classification.
+    /// </summary>
+    [JsonPropertyName("caseFileClassifications")]
+    public IReadOnlyList<FiksArkivClassification>? CaseFileClassifications { get; set; }
+
     /// <summary>
     /// The title to use for the generated journalpost (journal entry) element in the arkivmelding.xml.
     /// If no title is provided, the value will default to the application title as defined in applicationmetadata.json.
@@ -141,6 +148,11 @@ internal void Validate(IReadOnlyList<DataType> dataTypes, IAppModel appModelReso
         CaseFileId?.Validate($"{propertyName}.{nameof(CaseFileId)}", dataTypes, appModelResolver);
         CaseFileTitle?.Validate($"{propertyName}.{nameof(CaseFileTitle)}", dataTypes, appModelResolver);
         JournalEntryTitle?.Validate($"{propertyName}.{nameof(JournalEntryTitle)}", dataTypes, appModelResolver);
+
+        foreach (var classification in CaseFileClassifications ?? [])
+        {
+            classification.Validate($"{propertyName}.{nameof(CaseFileClassifications)}");
+        }
     }
 }
 
@@ -411,6 +423,13 @@ public sealed record FiksArkivDataTypeSettings
     [JsonPropertyName("filename")]
     public string? Filename { get; set; }
 
+    /// <summary>
+    /// Optional override for the document format code (e.g. <c>PDF/A</c>) recorded in the arkivmelding.xml
+    /// (<c>dokumentobjekt.format.kode</c>). If not specified, the dotless file extension is used.
+    /// </summary>
+    [JsonPropertyName("formatCode")]
+    public string? FormatCode { get; set; }
+
     /// <summary>
     /// Internal validation based on the requirements of <see cref="FiksArkivDefaultPayloadGenerator"/>
     /// </summary>
@@ -429,6 +448,11 @@ internal void Validate(string propertyName, IReadOnlyList<DataType> dataTypes, b
             throw new FiksArkivConfigurationException(
                 $"{propertyName}.{nameof(Filename)} configuration is required, but missing."
             );
+
+        if (FormatCode is not null && string.IsNullOrWhiteSpace(FormatCode))
+            throw new FiksArkivConfigurationException(
+                $"{propertyName}.{nameof(FormatCode)} cannot be empty or whitespace if specified."
+            );
     }
 
     /// <summary>
@@ -437,3 +461,53 @@ internal void Validate(string propertyName, IReadOnlyList<DataType> dataTypes, b
     public string GetFilenameOrDefault(string defaultExtension = "xml") =>
         !string.IsNullOrWhiteSpace(Filename) ? Filename : $"{DataType}.{defaultExtension.TrimStart('.')}";
 }
+
+/// <summary>
+/// Represents a single classification (klassifikasjon) entry attached to the saksmappe (case file)
+/// in the generated arkivmelding.xml.
+/// </summary>
+public sealed record FiksArkivClassification
+{
+    /// <summary>
+    /// The identifier of the classification system this entry belongs to (klassifikasjonssystemID).
+    /// </summary>
+    [JsonPropertyName("systemId")]
+    public required string SystemId { get; set; }
+
+    /// <summary>
+    /// The identifier of the class within the classification system (klasseID).
+    /// </summary>
+    [JsonPropertyName("classificationId")]
+    public required string ClassificationId { get; set; }
+
+    /// <summary>
+    /// A human-readable title for the classification entry (tittel).
+    /// </summary>
+    [JsonPropertyName("title")]
+    public required string Title { get; set; }
+
+    /// <summary>
+    /// Optional flag indicating that the classification is restricted (erSkjermet).
+    /// Leave <c>null</c> to omit the property from the resulting XML.
+    /// </summary>
+    [JsonPropertyName("isRestricted")]
+    public bool? IsRestricted { get; set; }
+
+    internal void Validate(string propertyName)
+    {
+        if (string.IsNullOrWhiteSpace(SystemId))
+            throw new FiksArkivConfigurationException(
+                $"{propertyName}.{nameof(SystemId)} configuration is required, but missing."
+            );
+
+        if (string.IsNullOrWhiteSpace(ClassificationId))
+            throw new FiksArkivConfigurationException(
+                $"{propertyName}.{nameof(ClassificationId)} configuration is required, but missing."
+            );
+
+        if (string.IsNullOrWhiteSpace(Title))
+            throw new FiksArkivConfigurationException(
+                $"{propertyName}.{nameof(Title)} configuration is required, but missing."
+            );
+    }
+}
diff --git a/src/Altinn.App.Clients.Fiks/FiksArkiv/Models/MessagePayloadWrapper.cs b/src/Altinn.App.Clients.Fiks/FiksArkiv/Models/MessagePayloadWrapper.cs
index 18e451320a..1756c79d14 100644
--- a/src/Altinn.App.Clients.Fiks/FiksArkiv/Models/MessagePayloadWrapper.cs
+++ b/src/Altinn.App.Clients.Fiks/FiksArkiv/Models/MessagePayloadWrapper.cs
@@ -1,6 +1,16 @@
 using Altinn.App.Clients.Fiks.FiksIO.Models;
-using KS.Fiks.Arkiv.Models.V1.Kodelister;
+using KS.Fiks.Arkiv.Models.V1.Metadatakatalog;
+using Kode = KS.Fiks.Arkiv.Models.V1.Kodelister.Kode;
 
 namespace Altinn.App.Clients.Fiks.FiksArkiv.Models;
 
-internal sealed record MessagePayloadWrapper(FiksIOMessagePayload Payload, Kode FileTypeCode);
+internal sealed record MessagePayloadWrapper(FiksIOMessagePayload Payload, Kode FileTypeCode, string? FileFormatCode)
+{
+    public Format GetFileFormat() =>
+        new()
+        {
+            KodeProperty = !string.IsNullOrWhiteSpace(FileFormatCode)
+                ? FileFormatCode
+                : Payload.GetDotlessFileExtension(),
+        };
+}
diff --git a/test/Altinn.App.Clients.Fiks.Tests/Extensions/ListExtensionsTests.cs b/test/Altinn.App.Clients.Fiks.Tests/Extensions/ListExtensionsTests.cs
index 615178fce5..9ce64af0ca 100644
--- a/test/Altinn.App.Clients.Fiks.Tests/Extensions/ListExtensionsTests.cs
+++ b/test/Altinn.App.Clients.Fiks.Tests/Extensions/ListExtensionsTests.cs
@@ -12,7 +12,8 @@ private static IReadOnlyList<MessagePayloadWrapper> GetPayloads(params string[]
         return filenames
             .Select(filename => new MessagePayloadWrapper(
                 new FiksIOMessagePayload(filename, Stream.Null),
-                new Kode(".", string.Empty)
+                new Kode(".", string.Empty),
+                FileFormatCode: null
             ))
             .ToList();
     }
diff --git a/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivConfigResolverTest.GetInstanceOwnerClassification_ReturnsExpectedValue_ForKnownAuthenticationTypes.Org.verified.txt b/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivConfigResolverTest.GetCaseFileClassifications_ReturnsOwnerClassification_ForKnownAuthenticationTypes.Org.verified.txt
similarity index 80%
rename from test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivConfigResolverTest.GetInstanceOwnerClassification_ReturnsExpectedValue_ForKnownAuthenticationTypes.Org.verified.txt
rename to test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivConfigResolverTest.GetCaseFileClassifications_ReturnsOwnerClassification_ForKnownAuthenticationTypes.Org.verified.txt
index df1b4569ab..c54df44b7b 100644
--- a/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivConfigResolverTest.GetInstanceOwnerClassification_ReturnsExpectedValue_ForKnownAuthenticationTypes.Org.verified.txt
+++ b/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivConfigResolverTest.GetCaseFileClassifications_ReturnsOwnerClassification_ForKnownAuthenticationTypes.Org.verified.txt
@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
 <klassifikasjon xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/arkivmelding/opprett/v1">
-  <klassifikasjonssystemID>Organisasjonsnummer</klassifikasjonssystemID>
+  <klassifikasjonssystemID>ORGNR</klassifikasjonssystemID>
   <klasseID>405003309</klasseID>
 </klassifikasjon>
\ No newline at end of file
diff --git a/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivConfigResolverTest.GetInstanceOwnerClassification_ReturnsExpectedValue_ForKnownAuthenticationTypes.ServiceOwner.verified.txt b/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivConfigResolverTest.GetCaseFileClassifications_ReturnsOwnerClassification_ForKnownAuthenticationTypes.ServiceOwner.verified.txt
similarity index 81%
rename from test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivConfigResolverTest.GetInstanceOwnerClassification_ReturnsExpectedValue_ForKnownAuthenticationTypes.ServiceOwner.verified.txt
rename to test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivConfigResolverTest.GetCaseFileClassifications_ReturnsOwnerClassification_ForKnownAuthenticationTypes.ServiceOwner.verified.txt
index 1b26e0750b..3375594991 100644
--- a/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivConfigResolverTest.GetInstanceOwnerClassification_ReturnsExpectedValue_ForKnownAuthenticationTypes.ServiceOwner.verified.txt
+++ b/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivConfigResolverTest.GetCaseFileClassifications_ReturnsOwnerClassification_ForKnownAuthenticationTypes.ServiceOwner.verified.txt
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="utf-8"?>
 <klassifikasjon xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/arkivmelding/opprett/v1">
-  <klassifikasjonssystemID>Organisasjonsnummer</klassifikasjonssystemID>
+  <klassifikasjonssystemID>ORGNR</klassifikasjonssystemID>
   <klasseID>405003309</klasseID>
   <tittel>tdd</tittel>
 </klassifikasjon>
\ No newline at end of file
diff --git a/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivConfigResolverTest.GetInstanceOwnerClassification_ReturnsExpectedValue_ForKnownAuthenticationTypes.SystemUser.verified.txt b/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivConfigResolverTest.GetCaseFileClassifications_ReturnsOwnerClassification_ForKnownAuthenticationTypes.SystemUser.verified.txt
similarity index 82%
rename from test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivConfigResolverTest.GetInstanceOwnerClassification_ReturnsExpectedValue_ForKnownAuthenticationTypes.SystemUser.verified.txt
rename to test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivConfigResolverTest.GetCaseFileClassifications_ReturnsOwnerClassification_ForKnownAuthenticationTypes.SystemUser.verified.txt
index b5e8b61a20..30b064600f 100644
--- a/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivConfigResolverTest.GetInstanceOwnerClassification_ReturnsExpectedValue_ForKnownAuthenticationTypes.SystemUser.verified.txt
+++ b/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivConfigResolverTest.GetCaseFileClassifications_ReturnsOwnerClassification_ForKnownAuthenticationTypes.SystemUser.verified.txt
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="utf-8"?>
 <klassifikasjon xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/arkivmelding/opprett/v1">
-  <klassifikasjonssystemID>SystembrukerId</klassifikasjonssystemID>
+  <klassifikasjonssystemID>AltinnSystembrukerId</klassifikasjonssystemID>
   <klasseID>f58fe166-bc22-4899-beb7-c3e8e3332f43</klasseID>
   <tittel>310702641</tittel>
 </klassifikasjon>
\ No newline at end of file
diff --git a/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivConfigResolverTest.GetInstanceOwnerClassification_ReturnsExpectedValue_ForKnownAuthenticationTypes.User.verified.txt b/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivConfigResolverTest.GetCaseFileClassifications_ReturnsOwnerClassification_ForKnownAuthenticationTypes.User.verified.txt
similarity index 79%
rename from test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivConfigResolverTest.GetInstanceOwnerClassification_ReturnsExpectedValue_ForKnownAuthenticationTypes.User.verified.txt
rename to test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivConfigResolverTest.GetCaseFileClassifications_ReturnsOwnerClassification_ForKnownAuthenticationTypes.User.verified.txt
index 412d42207f..83334a6882 100644
--- a/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivConfigResolverTest.GetInstanceOwnerClassification_ReturnsExpectedValue_ForKnownAuthenticationTypes.User.verified.txt
+++ b/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivConfigResolverTest.GetCaseFileClassifications_ReturnsOwnerClassification_ForKnownAuthenticationTypes.User.verified.txt
@@ -1,6 +1,7 @@
 <?xml version="1.0" encoding="utf-8"?>
 <klassifikasjon xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/arkivmelding/opprett/v1">
-  <klassifikasjonssystemID>Fødselsnummer</klassifikasjonssystemID>
+  <klassifikasjonssystemID>PNR</klassifikasjonssystemID>
   <klasseID>12345678901</klasseID>
   <tittel>Test Testesen</tittel>
+  <erSkjermet>true</erSkjermet>
 </klassifikasjon>
\ No newline at end of file
diff --git a/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivDefaultPayloadGeneratorTest.GeneratePayload_GeneratesCorrectPayload.1.verified.txt b/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivDefaultPayloadGeneratorTest.GeneratePayload_GeneratesCorrectPayload.1.verified.txt
index c05767faa9..7d4ecc35dd 100644
--- a/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivDefaultPayloadGeneratorTest.GeneratePayload_GeneratesCorrectPayload.1.verified.txt
+++ b/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivDefaultPayloadGeneratorTest.GeneratePayload_GeneratesCorrectPayload.1.verified.txt
@@ -6,9 +6,10 @@
     <tittel>Test app</tittel>
     <offentligTittel>Test app</offentligTittel>
     <klassifikasjon>
-      <klassifikasjonssystemID>Fødselsnummer</klassifikasjonssystemID>
+      <klassifikasjonssystemID>PNR</klassifikasjonssystemID>
       <klasseID>12345678901</klasseID>
       <tittel>Test Testesen</tittel>
+      <erSkjermet>true</erSkjermet>
     </klassifikasjon>
     <referanseEksternNoekkel>
       <fagsystem xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">ttd/test-app</fagsystem>
@@ -39,16 +40,15 @@
         <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Dokumentet er ferdigstilt</beskrivelse>
       </dokumentstatus>
       <tittel>model.xml</tittel>
-      <opprettetDato>2025-10-24T09:58:00</opprettetDato>
+      <opprettetDato>2025-10-24T09:58:00Z</opprettetDato>
       <tilknyttetRegistreringSom>
         <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">H</kode>
         <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Hoveddokument</beskrivelse>
       </tilknyttetRegistreringSom>
       <dokumentobjekt>
-        <systemID label="Altinn Studio">f41af07b-47c3-4d3a-9a34-1baa0f575101</systemID>
         <variantformat>
-          <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">P</kode>
-          <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Produksjonsformat</beskrivelse>
+          <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">A</kode>
+          <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Arkivformat</beskrivelse>
         </variantformat>
         <format>
           <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">XML</kode>
@@ -67,16 +67,15 @@
         <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Dokumentet er ferdigstilt</beskrivelse>
       </dokumentstatus>
       <tittel>ref-data-as-pdf.pdf</tittel>
-      <opprettetDato>2025-10-24T09:58:00</opprettetDato>
+      <opprettetDato>2025-10-24T09:58:00Z</opprettetDato>
       <tilknyttetRegistreringSom>
         <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">V</kode>
         <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Vedlegg</beskrivelse>
       </tilknyttetRegistreringSom>
       <dokumentobjekt>
-        <systemID label="Altinn Studio">f41af07b-47c3-4d3a-9a34-1baa0f575101</systemID>
         <variantformat>
-          <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">P</kode>
-          <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Produksjonsformat</beskrivelse>
+          <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">A</kode>
+          <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Arkivformat</beskrivelse>
         </variantformat>
         <format>
           <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">PDF</kode>
@@ -109,6 +108,6 @@
       <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Journalført</beskrivelse>
     </journalstatus>
     <dokumentetsDato>2025-10-24</dokumentetsDato>
-    <sendtDato>2025-10-24T09:58:00</sendtDato>
+    <sendtDato>2025-10-24T09:58:00Z</sendtDato>
   </registrering>
 </arkivmelding>
\ No newline at end of file
diff --git a/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivDefaultPayloadGeneratorTest.GeneratePayload_GeneratesCorrectPayload.2.verified.txt b/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivDefaultPayloadGeneratorTest.GeneratePayload_GeneratesCorrectPayload.2.verified.txt
index 862512b2fb..ec3829b7e1 100644
--- a/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivDefaultPayloadGeneratorTest.GeneratePayload_GeneratesCorrectPayload.2.verified.txt
+++ b/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivDefaultPayloadGeneratorTest.GeneratePayload_GeneratesCorrectPayload.2.verified.txt
@@ -7,7 +7,7 @@
     <tittel>Custom Case File Title</tittel>
     <offentligTittel>Custom Case File Title</offentligTittel>
     <klassifikasjon>
-      <klassifikasjonssystemID>SystembrukerId</klassifikasjonssystemID>
+      <klassifikasjonssystemID>AltinnSystembrukerId</klassifikasjonssystemID>
       <klasseID>f58fe166-bc22-4899-beb7-c3e8e3332f43</klasseID>
       <tittel>310702641</tittel>
     </klassifikasjon>
@@ -40,16 +40,15 @@
         <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Dokumentet er ferdigstilt</beskrivelse>
       </dokumentstatus>
       <tittel>Form.xml</tittel>
-      <opprettetDato>2025-10-24T09:58:00</opprettetDato>
+      <opprettetDato>2025-10-24T09:58:00Z</opprettetDato>
       <tilknyttetRegistreringSom>
         <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">H</kode>
         <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Hoveddokument</beskrivelse>
       </tilknyttetRegistreringSom>
       <dokumentobjekt>
-        <systemID label="Altinn Studio">f41af07b-47c3-4d3a-9a34-1baa0f575101</systemID>
         <variantformat>
-          <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">P</kode>
-          <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Produksjonsformat</beskrivelse>
+          <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">A</kode>
+          <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Arkivformat</beskrivelse>
         </variantformat>
         <format>
           <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">XML</kode>
@@ -68,16 +67,15 @@
         <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Dokumentet er ferdigstilt</beskrivelse>
       </dokumentstatus>
       <tittel>Form.pdf</tittel>
-      <opprettetDato>2025-10-24T09:58:00</opprettetDato>
+      <opprettetDato>2025-10-24T09:58:00Z</opprettetDato>
       <tilknyttetRegistreringSom>
         <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">V</kode>
         <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Vedlegg</beskrivelse>
       </tilknyttetRegistreringSom>
       <dokumentobjekt>
-        <systemID label="Altinn Studio">f41af07b-47c3-4d3a-9a34-1baa0f575101</systemID>
         <variantformat>
-          <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">P</kode>
-          <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Produksjonsformat</beskrivelse>
+          <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">A</kode>
+          <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Arkivformat</beskrivelse>
         </variantformat>
         <format>
           <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">PDF</kode>
@@ -96,16 +94,15 @@
         <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Dokumentet er ferdigstilt</beskrivelse>
       </dokumentstatus>
       <tittel>receipt2.pdf</tittel>
-      <opprettetDato>2025-10-24T09:58:00</opprettetDato>
+      <opprettetDato>2025-10-24T09:58:00Z</opprettetDato>
       <tilknyttetRegistreringSom>
         <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">V</kode>
         <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Vedlegg</beskrivelse>
       </tilknyttetRegistreringSom>
       <dokumentobjekt>
-        <systemID label="Altinn Studio">f41af07b-47c3-4d3a-9a34-1baa0f575101</systemID>
         <variantformat>
-          <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">P</kode>
-          <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Produksjonsformat</beskrivelse>
+          <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">A</kode>
+          <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Arkivformat</beskrivelse>
         </variantformat>
         <format>
           <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">PDF</kode>
@@ -124,16 +121,15 @@
         <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Dokumentet er ferdigstilt</beskrivelse>
       </dokumentstatus>
       <tittel>letter.docx</tittel>
-      <opprettetDato>2025-10-24T09:58:00</opprettetDato>
+      <opprettetDato>2025-10-24T09:58:00Z</opprettetDato>
       <tilknyttetRegistreringSom>
         <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">V</kode>
         <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Vedlegg</beskrivelse>
       </tilknyttetRegistreringSom>
       <dokumentobjekt>
-        <systemID label="Altinn Studio">f41af07b-47c3-4d3a-9a34-1baa0f575101</systemID>
         <variantformat>
-          <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">P</kode>
-          <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Produksjonsformat</beskrivelse>
+          <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">A</kode>
+          <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Arkivformat</beskrivelse>
         </variantformat>
         <format>
           <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">DOCX</kode>
@@ -152,16 +148,15 @@
         <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Dokumentet er ferdigstilt</beskrivelse>
       </dokumentstatus>
       <tittel>drawing_1a.jpg</tittel>
-      <opprettetDato>2025-10-24T09:58:00</opprettetDato>
+      <opprettetDato>2025-10-24T09:58:00Z</opprettetDato>
       <tilknyttetRegistreringSom>
         <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">V</kode>
         <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Vedlegg</beskrivelse>
       </tilknyttetRegistreringSom>
       <dokumentobjekt>
-        <systemID label="Altinn Studio">f41af07b-47c3-4d3a-9a34-1baa0f575101</systemID>
         <variantformat>
-          <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">P</kode>
-          <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Produksjonsformat</beskrivelse>
+          <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">A</kode>
+          <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Arkivformat</beskrivelse>
         </variantformat>
         <format>
           <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">JPG</kode>
@@ -194,6 +189,6 @@
       <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Journalført</beskrivelse>
     </journalstatus>
     <dokumentetsDato>2025-10-24</dokumentetsDato>
-    <sendtDato>2025-10-24T09:58:00</sendtDato>
+    <sendtDato>2025-10-24T09:58:00Z</sendtDato>
   </registrering>
 </arkivmelding>
\ No newline at end of file
diff --git a/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivDefaultPayloadGeneratorTest.GeneratePayload_GeneratesCorrectPayload.3.verified.txt b/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivDefaultPayloadGeneratorTest.GeneratePayload_GeneratesCorrectPayload.3.verified.txt
index ac24e3402e..3a01d9b5dd 100644
--- a/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivDefaultPayloadGeneratorTest.GeneratePayload_GeneratesCorrectPayload.3.verified.txt
+++ b/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivDefaultPayloadGeneratorTest.GeneratePayload_GeneratesCorrectPayload.3.verified.txt
@@ -6,7 +6,7 @@
     <tittel>Test app</tittel>
     <offentligTittel>Test app</offentligTittel>
     <klassifikasjon>
-      <klassifikasjonssystemID>Organisasjonsnummer</klassifikasjonssystemID>
+      <klassifikasjonssystemID>ORGNR</klassifikasjonssystemID>
       <klasseID>405003309</klasseID>
       <tittel>tdd</tittel>
     </klassifikasjon>
@@ -39,16 +39,15 @@
         <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Dokumentet er ferdigstilt</beskrivelse>
       </dokumentstatus>
       <tittel>Form.xml</tittel>
-      <opprettetDato>2025-10-24T09:58:00</opprettetDato>
+      <opprettetDato>2025-10-24T09:58:00Z</opprettetDato>
       <tilknyttetRegistreringSom>
         <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">H</kode>
         <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Hoveddokument</beskrivelse>
       </tilknyttetRegistreringSom>
       <dokumentobjekt>
-        <systemID label="Altinn Studio">f41af07b-47c3-4d3a-9a34-1baa0f575101</systemID>
         <variantformat>
-          <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">P</kode>
-          <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Produksjonsformat</beskrivelse>
+          <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">A</kode>
+          <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Arkivformat</beskrivelse>
         </variantformat>
         <format>
           <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">XML</kode>
@@ -97,6 +96,6 @@
       <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Journalført</beskrivelse>
     </journalstatus>
     <dokumentetsDato>2025-10-24</dokumentetsDato>
-    <sendtDato>2025-10-24T09:58:00</sendtDato>
+    <sendtDato>2025-10-24T09:58:00Z</sendtDato>
   </registrering>
 </arkivmelding>
\ No newline at end of file
diff --git a/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivDefaultPayloadGeneratorTest.GeneratePayload_GeneratesCorrectPayload.4.verified.txt b/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivDefaultPayloadGeneratorTest.GeneratePayload_GeneratesCorrectPayload.4.verified.txt
index e643c82339..15767f0c05 100644
--- a/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivDefaultPayloadGeneratorTest.GeneratePayload_GeneratesCorrectPayload.4.verified.txt
+++ b/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivDefaultPayloadGeneratorTest.GeneratePayload_GeneratesCorrectPayload.4.verified.txt
@@ -6,7 +6,7 @@
     <tittel>Custom Case File Title</tittel>
     <offentligTittel>Custom Case File Title</offentligTittel>
     <klassifikasjon>
-      <klassifikasjonssystemID>Organisasjonsnummer</klassifikasjonssystemID>
+      <klassifikasjonssystemID>ORGNR</klassifikasjonssystemID>
       <klasseID>405003309</klasseID>
     </klassifikasjon>
     <referanseEksternNoekkel>
@@ -38,16 +38,15 @@
         <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Dokumentet er ferdigstilt</beskrivelse>
       </dokumentstatus>
       <tittel>Form.xml</tittel>
-      <opprettetDato>2025-10-24T09:58:00</opprettetDato>
+      <opprettetDato>2025-10-24T09:58:00Z</opprettetDato>
       <tilknyttetRegistreringSom>
         <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">H</kode>
         <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Hoveddokument</beskrivelse>
       </tilknyttetRegistreringSom>
       <dokumentobjekt>
-        <systemID label="Altinn Studio">f41af07b-47c3-4d3a-9a34-1baa0f575101</systemID>
         <variantformat>
-          <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">P</kode>
-          <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Produksjonsformat</beskrivelse>
+          <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">A</kode>
+          <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Arkivformat</beskrivelse>
         </variantformat>
         <format>
           <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">XML</kode>
@@ -91,6 +90,6 @@
       <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Journalført</beskrivelse>
     </journalstatus>
     <dokumentetsDato>2025-10-24</dokumentetsDato>
-    <sendtDato>2025-10-24T09:58:00</sendtDato>
+    <sendtDato>2025-10-24T09:58:00Z</sendtDato>
   </registrering>
 </arkivmelding>
\ No newline at end of file
diff --git a/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivDefaultPayloadGeneratorTest.GeneratePayload_GeneratesCorrectPayload.5.verified.txt b/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivDefaultPayloadGeneratorTest.GeneratePayload_GeneratesCorrectPayload.5.verified.txt
new file mode 100644
index 0000000000..9b7b4f2587
--- /dev/null
+++ b/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/.Verify/FiksArkivDefaultPayloadGeneratorTest.GeneratePayload_GeneratesCorrectPayload.5.verified.txt
@@ -0,0 +1,124 @@
+<?xml version="1.0" encoding="utf-8"?>
+<arkivmelding xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/arkivmelding/opprett/v1">
+  <system>Altinn Studio</system>
+  <antallFiler>2</antallFiler>
+  <mappe xsi:type="saksmappe">
+    <tittel>Test app</tittel>
+    <offentligTittel>Test app</offentligTittel>
+    <klassifikasjon>
+      <klassifikasjonssystemID>PNR</klassifikasjonssystemID>
+      <klasseID>12345678901</klasseID>
+      <tittel>Test Testesen</tittel>
+      <erSkjermet>true</erSkjermet>
+    </klassifikasjon>
+    <klassifikasjon>
+      <klassifikasjonssystemID>custom-system</klassifikasjonssystemID>
+      <klasseID>custom-class</klasseID>
+      <tittel>Custom Classification</tittel>
+    </klassifikasjon>
+    <klassifikasjon>
+      <klassifikasjonssystemID>custom-system-2</klassifikasjonssystemID>
+      <klasseID>custom-class-2</klasseID>
+      <tittel>Restricted Classification</tittel>
+      <erSkjermet>true</erSkjermet>
+    </klassifikasjon>
+    <referanseEksternNoekkel>
+      <fagsystem xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">ttd/test-app</fagsystem>
+      <noekkel xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">12345/88d9baf8-2f9f-4e66-9a2f-7d345e60ed90</noekkel>
+    </referanseEksternNoekkel>
+    <saksaar>2025</saksaar>
+    <saksdato>2025-10-24</saksdato>
+    <administrativEnhet>
+      <navn xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">ttd</navn>
+    </administrativEnhet>
+  </mappe>
+  <registrering xsi:type="journalpost">
+    <opprettetAv>ttd</opprettetAv>
+    <arkivertAv>ttd</arkivertAv>
+    <referanseForelderMappe>
+      <referanseEksternNoekkel xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">
+        <fagsystem>ttd/test-app</fagsystem>
+        <noekkel>12345/88d9baf8-2f9f-4e66-9a2f-7d345e60ed90</noekkel>
+      </referanseEksternNoekkel>
+    </referanseForelderMappe>
+    <dokumentbeskrivelse>
+      <dokumenttype>
+        <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">DOKUMENT</kode>
+        <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Dokument</beskrivelse>
+      </dokumenttype>
+      <dokumentstatus>
+        <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">F</kode>
+        <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Dokumentet er ferdigstilt</beskrivelse>
+      </dokumentstatus>
+      <tittel>Form.pdf</tittel>
+      <opprettetDato>2025-10-24T09:58:00Z</opprettetDato>
+      <tilknyttetRegistreringSom>
+        <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">H</kode>
+        <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Hoveddokument</beskrivelse>
+      </tilknyttetRegistreringSom>
+      <dokumentobjekt>
+        <variantformat>
+          <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">A</kode>
+          <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Arkivformat</beskrivelse>
+        </variantformat>
+        <format>
+          <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">PDF/A</kode>
+        </format>
+        <filnavn>Form.pdf</filnavn>
+        <referanseDokumentfil>Form.pdf</referanseDokumentfil>
+      </dokumentobjekt>
+    </dokumentbeskrivelse>
+    <dokumentbeskrivelse>
+      <dokumenttype>
+        <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">VEDLEGG</kode>
+        <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Vedlegg</beskrivelse>
+      </dokumenttype>
+      <dokumentstatus>
+        <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">F</kode>
+        <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Dokumentet er ferdigstilt</beskrivelse>
+      </dokumentstatus>
+      <tittel>ref-data-as-pdf.pdf</tittel>
+      <opprettetDato>2025-10-24T09:58:00Z</opprettetDato>
+      <tilknyttetRegistreringSom>
+        <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">V</kode>
+        <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Vedlegg</beskrivelse>
+      </tilknyttetRegistreringSom>
+      <dokumentobjekt>
+        <variantformat>
+          <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">A</kode>
+          <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Arkivformat</beskrivelse>
+        </variantformat>
+        <format>
+          <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">PDF</kode>
+        </format>
+        <filnavn>ref-data-as-pdf.pdf</filnavn>
+        <referanseDokumentfil>ref-data-as-pdf.pdf</referanseDokumentfil>
+      </dokumentobjekt>
+    </dokumentbeskrivelse>
+    <tittel>Test app</tittel>
+    <offentligTittel>Test app</offentligTittel>
+    <korrespondansepart>
+      <korrespondansepartID>recipient-id</korrespondansepartID>
+      <korrespondanseparttype>
+        <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">EM</kode>
+        <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Mottaker</beskrivelse>
+      </korrespondanseparttype>
+      <korrespondansepartNavn>Recipient Name</korrespondansepartNavn>
+    </korrespondansepart>
+    <referanseEksternNoekkel>
+      <fagsystem xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">ttd/test-app</fagsystem>
+      <noekkel xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">12345/88d9baf8-2f9f-4e66-9a2f-7d345e60ed90</noekkel>
+    </referanseEksternNoekkel>
+    <journalaar>2025</journalaar>
+    <journalposttype>
+      <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">I</kode>
+      <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Inngående dokument</beskrivelse>
+    </journalposttype>
+    <journalstatus>
+      <kode xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">J</kode>
+      <beskrivelse xmlns="https://ks-no.github.io/standarder/fiks-protokoll/fiks-arkiv/metadatakatalog/v1">Journalført</beskrivelse>
+    </journalstatus>
+    <dokumentetsDato>2025-10-24</dokumentetsDato>
+    <sendtDato>2025-10-24T09:58:00Z</sendtDato>
+  </registrering>
+</arkivmelding>
\ No newline at end of file
diff --git a/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/FiksArkivConfigResolverTest.cs b/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/FiksArkivConfigResolverTest.cs
index 47b4071fda..7569076b86 100644
--- a/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/FiksArkivConfigResolverTest.cs
+++ b/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/FiksArkivConfigResolverTest.cs
@@ -455,7 +455,7 @@ public async Task GetRecipientParty_ReturnsExpectedValue(
     [InlineData(typeof(Authenticated.SystemUser))]
     [InlineData(typeof(Authenticated.ServiceOwner))]
     [InlineData(typeof(Authenticated.Org))]
-    public async Task GetInstanceOwnerClassification_ReturnsExpectedValue_ForKnownAuthenticationTypes(Type authType)
+    public async Task GetCaseFileClassifications_ReturnsOwnerClassification_ForKnownAuthenticationTypes(Type authType)
     {
         // Arrange
         Authenticated auth = authType switch
@@ -469,20 +469,24 @@ public async Task GetInstanceOwnerClassification_ReturnsExpectedValue_ForKnownAu
             _ => throw new NotSupportedException(),
         };
 
-        await using var fixture = TestFixture.Create(services => services.AddFiksArkiv());
+        await using var fixture = TestFixture.Create(
+            services => services.AddFiksArkiv(),
+            useDefaultFiksArkivSettings: false
+        );
 
         // Act
-        var result = await fixture.FiksArkivConfigResolver.GetInstanceOwnerClassification(auth);
+        var result = await fixture.FiksArkivConfigResolver.GetCaseFileClassifications(auth);
 
         // Assert
         Assert.NotNull(result);
-        var serialized = result.SerializeXml(indent: true);
+        Assert.Single(result);
+        var serialized = result[0].SerializeXml(indent: true);
         var xml = Encoding.UTF8.GetString(serialized.Span);
         await Verify(xml).UseDefaultSettings(authType.Name.Split("+").Last());
     }
 
     [Fact]
-    public async Task GetInstanceOwnerClassification_ThrowsException_ForUnknownAuthenticationTypes()
+    public async Task GetCaseFileClassifications_ThrowsException_ForUnknownAuthenticationTypes()
     {
         // Arrange
         var auth = TestAuthentication.GetNoneAuthentication();
@@ -490,10 +494,77 @@ public async Task GetInstanceOwnerClassification_ThrowsException_ForUnknownAuthe
 
         // Act
         await Assert.ThrowsAsync<FiksArkivException>(() =>
-            fixture.FiksArkivConfigResolver.GetInstanceOwnerClassification(auth)
+            fixture.FiksArkivConfigResolver.GetCaseFileClassifications(auth)
         );
     }
 
+    [Fact]
+    public async Task GetCaseFileClassifications_AppendsConfiguredClassifications_AfterOwnerClassification()
+    {
+        // Arrange
+        var fiksArkivSettingsOverride = new FiksArkivSettings
+        {
+            Metadata = new FiksArkivMetadataSettings
+            {
+                CaseFileClassifications =
+                [
+                    new FiksArkivClassification
+                    {
+                        SystemId = "configured-system-1",
+                        ClassificationId = "configured-class-1",
+                        Title = "Configured 1",
+                    },
+                    new FiksArkivClassification
+                    {
+                        SystemId = "configured-system-2",
+                        ClassificationId = "configured-class-2",
+                        Title = "Configured 2",
+                        IsRestricted = true,
+                    },
+                ],
+            },
+        };
+        await using var fixture = TestFixture.Create(
+            services => services.AddFiksArkiv().WithFiksArkivConfig("CustomFiksArkivSettings"),
+            [("CustomFiksArkivSettings", fiksArkivSettingsOverride)],
+            useDefaultFiksArkivSettings: false
+        );
+
+        // Act
+        var result = await fixture.FiksArkivConfigResolver.GetCaseFileClassifications(
+            TestAuthentication.GetServiceOwnerAuthentication()
+        );
+
+        // Assert
+        Assert.Equal(3, result.Count);
+        Assert.Equal("configured-system-1", result[1].KlassifikasjonssystemID);
+        Assert.Equal("configured-class-1", result[1].KlasseID);
+        Assert.Equal("Configured 1", result[1].Tittel);
+        Assert.Null(result[1].ErSkjermet);
+        Assert.Equal("configured-system-2", result[2].KlassifikasjonssystemID);
+        Assert.Equal("configured-class-2", result[2].KlasseID);
+        Assert.Equal("Configured 2", result[2].Tittel);
+        Assert.True(result[2].ErSkjermet);
+    }
+
+    [Fact]
+    public async Task GetCaseFileClassifications_ReturnsOwnerOnly_WhenNoConfiguredClassifications()
+    {
+        // Arrange
+        await using var fixture = TestFixture.Create(
+            services => services.AddFiksArkiv(),
+            useDefaultFiksArkivSettings: false
+        );
+
+        // Act
+        var result = await fixture.FiksArkivConfigResolver.GetCaseFileClassifications(
+            TestAuthentication.GetServiceOwnerAuthentication()
+        );
+
+        // Assert
+        Assert.Single(result);
+    }
+
     // csharpier-ignore-start
     [Theory]
     [InlineData(1, PartyType.None, null, null, null, null, null, null, null, null)]
diff --git a/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/FiksArkivDefaultPayloadGeneratorTest.cs b/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/FiksArkivDefaultPayloadGeneratorTest.cs
index bd337b75a6..b77f671836 100644
--- a/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/FiksArkivDefaultPayloadGeneratorTest.cs
+++ b/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/FiksArkivDefaultPayloadGeneratorTest.cs
@@ -15,7 +15,6 @@
 using KS.Fiks.Arkiv.Models.V1.Arkivering.Arkivmelding;
 using Microsoft.Extensions.Hosting;
 using Microsoft.Extensions.Logging;
-using Microsoft.Extensions.Options;
 using Microsoft.Extensions.Time.Testing;
 using Moq;
 
@@ -26,19 +25,21 @@ public class FiksArkivDefaultPayloadGeneratorTest
     //Example Instance ID = "12345/88d9baf8-2f9f-4e66-9a2f-7d345e60ed90"
 
     private static readonly XsdValidator _xsdValidator = new();
-    private static readonly Guid _fiksIOSenderAccount = Guid.Parse("f41af07b-47c3-4d3a-9a34-1baa0f575101");
     private static readonly DateTimeOffset _now = DateTimeOffset.Parse("2025-10-24T09:58:00.000000Z");
 
-    private static readonly Instance _defaultInstance = Factories.Instance(
-        "12345/88d9baf8-2f9f-4e66-9a2f-7d345e60ed90",
-        [
-            Factories.DataElement("model", null, "application/xml"),
-            Factories.DataElement("ref-data-as-pdf", null, "application/pdf"),
-            Factories.DataElement("something-uploaded", "receipt2.pdf", null),
-            Factories.DataElement("something-uploaded", "letter.docx", null),
-            Factories.DataElement("something-uploaded", "drawing_1a.jpg", null),
-        ]
-    );
+    // Built fresh per test invocation because the production code mutates DataElement.Filename;
+    // reusing a static instance leaks state across test cases.
+    private static Instance NewDefaultInstance() =>
+        Factories.Instance(
+            "12345/88d9baf8-2f9f-4e66-9a2f-7d345e60ed90",
+            [
+                Factories.DataElement("model", null, "application/xml"),
+                Factories.DataElement("ref-data-as-pdf", null, "application/pdf"),
+                Factories.DataElement("something-uploaded", "receipt2.pdf", null),
+                Factories.DataElement("something-uploaded", "letter.docx", null),
+                Factories.DataElement("something-uploaded", "drawing_1a.jpg", null),
+            ]
+        );
 
     private static class Auth
     {
@@ -130,6 +131,27 @@ private static class Auth
                 ),
                 instanceOwnerClassification: Factories.InstanceOwnerClassification(Auth.Org)
             ),
+            TestCase.Create(
+                testIdentifier: "5",
+                fiksArkivMessageType: FiksArkivConstants.MessageTypes.CreateArchiveRecord,
+                expectedAttachmentFilenames: ["Form.pdf", "ref-data-as-pdf.pdf"],
+                primaryDocumentSettings: Factories.DocumentSettings("model", "Form.pdf", formatCode: "PDF/A"),
+                attachmentSettings: [Factories.DocumentSettings("ref-data-as-pdf")],
+                archiveDocumentMetadata: null,
+                recipientParty: Factories.RecipientParty("recipient-id", "Recipient Name"),
+                instanceOwnerParty: null,
+                instanceOwnerClassification: Factories.InstanceOwnerClassification(Auth.User),
+                additionalClassifications:
+                [
+                    Factories.ConfiguredClassification("custom-system", "custom-class", "Custom Classification"),
+                    Factories.ConfiguredClassification(
+                        "custom-system-2",
+                        "custom-class-2",
+                        "Restricted Classification",
+                        isRestricted: true
+                    ),
+                ]
+            ),
         ];
 
     [Theory]
@@ -141,7 +163,7 @@ internal async Task GeneratePayload_GeneratesCorrectPayload(TestCase testCase)
 
         // Act
         var result = await fixture.GeneratePayload(
-            _defaultInstance,
+            NewDefaultInstance(),
             FiksArkivConstants.MessageTypes.CreateArchiveRecord
         );
 
@@ -189,6 +211,7 @@ public static TestCase Create(
             Korrespondansepart recipientParty,
             Korrespondansepart? instanceOwnerParty,
             Klassifikasjon instanceOwnerClassification,
+            IReadOnlyList<Klassifikasjon>? additionalClassifications = null,
             string applicationTitle = "Test app",
             string appId = "ttd/test-app"
         )
@@ -201,6 +224,7 @@ public static TestCase Create(
                     recipientParty,
                     instanceOwnerParty,
                     instanceOwnerClassification,
+                    additionalClassifications,
                     applicationTitle,
                     appId
                 ),
@@ -242,6 +266,7 @@ public static PayloadGeneratorFixture Create(
             Korrespondansepart recipientParty,
             Korrespondansepart? instanceOwnerParty,
             Klassifikasjon instanceOwnerClassification,
+            IReadOnlyList<Klassifikasjon>? additionalClassifications = null,
             string applicationTitle = "Test app",
             string appId = "ttd/test-app"
         )
@@ -272,8 +297,8 @@ public static PayloadGeneratorFixture Create(
                 .Setup(x => x.GetInstanceOwnerParty(It.IsAny<Instance>(), It.IsAny<CancellationToken>()))
                 .ReturnsAsync(instanceOwnerParty);
             configResolverMock
-                .Setup(x => x.GetInstanceOwnerClassification(It.IsAny<Authenticated>(), It.IsAny<CancellationToken>()))
-                .ReturnsAsync(instanceOwnerClassification);
+                .Setup(x => x.GetCaseFileClassifications(It.IsAny<Authenticated>(), It.IsAny<CancellationToken>()))
+                .ReturnsAsync([instanceOwnerClassification, .. additionalClassifications ?? []]);
 
             var payloadGenerator = new FiksArkivDefaultPayloadGenerator(
                 appMetadataMock.Object,
@@ -282,7 +307,6 @@ public static PayloadGeneratorFixture Create(
                 loggerMock.Object,
                 Mock.Of<IHostEnvironment>(x => x.EnvironmentName == Environments.Development),
                 configResolverMock.Object,
-                Options.Create(Factories.FiksIOSettings(_fiksIOSenderAccount)),
                 fakeTime
             );
 
@@ -311,22 +335,36 @@ public static PayloadGeneratorFixture Create(
 
     private static class Factories
     {
-        public static FiksIOSettings FiksIOSettings(Guid accountId) =>
-            new()
-            {
-                AccountId = accountId,
-                IntegrationId = Guid.Empty,
-                IntegrationPassword = "-",
-                AccountPrivateKeyBase64 = "-",
-            };
-
         public static Instance Instance(string id, IEnumerable<DataElement> dataElements) =>
             new() { Id = id, Data = [.. dataElements] };
 
         public static FiksArkivRecipient Recipient() => new(Guid.NewGuid(), "-", "-", "-");
 
-        public static FiksArkivDataTypeSettings DocumentSettings(string dataType, string? filename = null) =>
-            new() { DataType = dataType, Filename = filename };
+        public static FiksArkivDataTypeSettings DocumentSettings(
+            string dataType,
+            string? filename = null,
+            string? formatCode = null
+        ) =>
+            new()
+            {
+                DataType = dataType,
+                Filename = filename,
+                FormatCode = formatCode,
+            };
+
+        public static Klassifikasjon ConfiguredClassification(
+            string systemId,
+            string classificationId,
+            string title,
+            bool? isRestricted = null
+        ) =>
+            new FiksArkivClassification
+            {
+                SystemId = systemId,
+                ClassificationId = classificationId,
+                Title = title,
+                IsRestricted = isRestricted,
+            }.ToKlassifikasjon();
 
         public static FiksArkivDocumentMetadata Metadata(
             string? systemId,
diff --git a/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/Models/FiksArkivDocumentsTest.cs b/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/Models/FiksArkivDocumentsTest.cs
index fb1df82e0f..be7107b7f8 100644
--- a/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/Models/FiksArkivDocumentsTest.cs
+++ b/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/Models/FiksArkivDocumentsTest.cs
@@ -11,7 +11,7 @@ public class FiksArkivDocumentsTest
     private static FiksIOMessagePayload CreatePayload(string filename) => new(filename, Stream.Null);
 
     private MessagePayloadWrapper CreateMessagePayloadWrapper(string filename, Kode? code = null) =>
-        new(CreatePayload(filename), code ?? _dummyCode);
+        new(CreatePayload(filename), code ?? _dummyCode, FileFormatCode: null);
 
     [Fact]
     public void ToPaylods_ContainsAllDocuments_InTheCorrectOrder()
diff --git a/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/Models/FiksArkivSettingsTest.cs b/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/Models/FiksArkivSettingsTest.cs
index f5e06d6858..5fea883b1d 100644
--- a/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/Models/FiksArkivSettingsTest.cs
+++ b/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/Models/FiksArkivSettingsTest.cs
@@ -1,4 +1,5 @@
 using Altinn.App.Clients.Fiks.Exceptions;
+using Altinn.App.Clients.Fiks.Extensions;
 using Altinn.App.Clients.Fiks.FiksArkiv.Models;
 using Altinn.Platform.Storage.Interface.Models;
 
@@ -6,6 +7,71 @@ namespace Altinn.App.Clients.Fiks.Tests.FiksArkiv.Models;
 
 public class FiksArkivSettingsTest
 {
+    [Theory]
+    [InlineData("sys", "cls", "title", null, null)]
+    [InlineData("sys", "cls", "title", true, null)]
+    [InlineData("sys", "cls", "title", false, null)]
+    [InlineData("", "cls", "title", null, "SystemId configuration is required")]
+    [InlineData("   ", "cls", "title", null, "SystemId configuration is required")]
+    [InlineData("sys", "", "title", null, "ClassificationId configuration is required")]
+    [InlineData("sys", "cls", "", null, "Title configuration is required")]
+    public void FiksArkivClassification_ValidatesCorrectly(
+        string systemId,
+        string classificationId,
+        string title,
+        bool? isRestricted,
+        string? expectedErrorMessage
+    )
+    {
+        // Arrange
+        var classification = new FiksArkivClassification
+        {
+            SystemId = systemId,
+            ClassificationId = classificationId,
+            Title = title,
+            IsRestricted = isRestricted,
+        };
+
+        // Act
+        var ex = Record.Exception(() => classification.Validate("TestSetting"));
+
+        // Assert
+        if (expectedErrorMessage is null)
+        {
+            Assert.Null(ex);
+            return;
+        }
+
+        Assert.NotNull(ex);
+        Assert.IsType<FiksArkivConfigurationException>(ex);
+        Assert.Contains(expectedErrorMessage, ex.Message);
+    }
+
+    [Theory]
+    [InlineData(null)]
+    [InlineData(true)]
+    [InlineData(false)]
+    public void FiksArkivClassification_ToKlassifikasjon_MapsAllFields(bool? isRestricted)
+    {
+        // Arrange
+        var classification = new FiksArkivClassification
+        {
+            SystemId = "system-1",
+            ClassificationId = "class-1",
+            Title = "The Title",
+            IsRestricted = isRestricted,
+        };
+
+        // Act
+        var result = classification.ToKlassifikasjon();
+
+        // Assert
+        Assert.Equal("system-1", result.KlassifikasjonssystemID);
+        Assert.Equal("class-1", result.KlasseID);
+        Assert.Equal("The Title", result.Tittel);
+        Assert.Equal(isRestricted, result.ErSkjermet);
+    }
+
     [Theory]
     [InlineData("datatype1", "customfile.xml", null, "customfile.xml")]
     [InlineData("datatype2", null, ".pdf", "datatype2.pdf")]
@@ -58,4 +124,30 @@ public void FiksArkivDataTypeSettings_ValidatesCorrectly(
         Assert.IsType<FiksArkivConfigurationException>(ex);
         Assert.Contains(expectedErrorMessage, ex.Message);
     }
+
+    [Theory]
+    [InlineData(null, null)]
+    [InlineData("PDF/A", null)]
+    [InlineData("anything goes verbatim", null)]
+    [InlineData("", "FormatCode cannot be empty or whitespace")]
+    [InlineData("   ", "FormatCode cannot be empty or whitespace")]
+    public void FiksArkivDataTypeSettings_ValidatesFormatCode(string? formatCode, string? expectedErrorMessage)
+    {
+        // Arrange
+        var settings = new FiksArkivDataTypeSettings { DataType = "valid-datatype", FormatCode = formatCode };
+
+        // Act
+        var ex = Record.Exception(() => settings.Validate("TestSetting", [new DataType { Id = "valid-datatype" }]));
+
+        // Assert
+        if (expectedErrorMessage is null)
+        {
+            Assert.Null(ex);
+            return;
+        }
+
+        Assert.NotNull(ex);
+        Assert.IsType<FiksArkivConfigurationException>(ex);
+        Assert.Contains(expectedErrorMessage, ex.Message);
+    }
 }
diff --git a/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/Models/MessagePayloadWrapperTest.cs b/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/Models/MessagePayloadWrapperTest.cs
new file mode 100644
index 0000000000..b8c8f97f21
--- /dev/null
+++ b/test/Altinn.App.Clients.Fiks.Tests/FiksArkiv/Models/MessagePayloadWrapperTest.cs
@@ -0,0 +1,58 @@
+using Altinn.App.Clients.Fiks.FiksArkiv.Models;
+using Altinn.App.Clients.Fiks.FiksIO.Models;
+using KS.Fiks.Arkiv.Models.V1.Kodelister;
+
+namespace Altinn.App.Clients.Fiks.Tests.FiksArkiv.Models;
+
+public class MessagePayloadWrapperTest
+{
+    private static readonly Kode _dummyCode = new(".", string.Empty);
+
+    [Theory]
+    [InlineData("PDF/A")]
+    [InlineData("XML")]
+    [InlineData("anything-goes")]
+    public void GetFileFormat_UsesOverride_WhenFormatCodeIsProvided(string formatCode)
+    {
+        var wrapper = new MessagePayloadWrapper(
+            new FiksIOMessagePayload("document.pdf", Stream.Null),
+            _dummyCode,
+            FileFormatCode: formatCode
+        );
+
+        var result = wrapper.GetFileFormat();
+
+        Assert.Equal(formatCode, result.KodeProperty);
+    }
+
+    [Theory]
+    [InlineData(null)]
+    [InlineData("")]
+    [InlineData("   ")]
+    public void GetFileFormat_FallsBackToFileExtension_WhenFormatCodeIsMissing(string? formatCode)
+    {
+        var wrapper = new MessagePayloadWrapper(
+            new FiksIOMessagePayload("report.pdf", Stream.Null),
+            _dummyCode,
+            FileFormatCode: formatCode
+        );
+
+        var result = wrapper.GetFileFormat();
+
+        Assert.Equal("PDF", result.KodeProperty);
+    }
+
+    [Fact]
+    public void GetFileFormat_FallsBackToUppercasedFilename_WhenNoExtensionAndNoOverride()
+    {
+        var wrapper = new MessagePayloadWrapper(
+            new FiksIOMessagePayload("extensionless", Stream.Null),
+            _dummyCode,
+            FileFormatCode: null
+        );
+
+        var result = wrapper.GetFileFormat();
+
+        Assert.Equal("EXTENSIONLESS", result.KodeProperty);
+    }
+}
diff --git a/test/Altinn.App.Clients.Fiks.Tests/PublicApiTests.PublicApi_ShouldNotChange_Unintentionally.verified.txt b/test/Altinn.App.Clients.Fiks.Tests/PublicApiTests.PublicApi_ShouldNotChange_Unintentionally.verified.txt
index 393181c7b5..7ead0b6e75 100644
--- a/test/Altinn.App.Clients.Fiks.Tests/PublicApiTests.PublicApi_ShouldNotChange_Unintentionally.verified.txt
+++ b/test/Altinn.App.Clients.Fiks.Tests/PublicApiTests.PublicApi_ShouldNotChange_Unintentionally.verified.txt
@@ -68,8 +68,8 @@ namespace Altinn.App.Clients.Fiks.FiksArkiv
         Altinn.App.Clients.Fiks.FiksArkiv.Models.FiksArkivDataTypeSettings PrimaryDocumentSettings { get; }
         System.Threading.Tasks.Task<string> GetApplicationTitle(System.Threading.CancellationToken cancellationToken = default);
         System.Threading.Tasks.Task<Altinn.App.Clients.Fiks.FiksArkiv.Models.FiksArkivDocumentMetadata?> GetArchiveDocumentMetadata(Altinn.Platform.Storage.Interface.Models.Instance instance, System.Threading.CancellationToken cancellationToken = default);
+        System.Threading.Tasks.Task<System.Collections.Generic.IReadOnlyList<KS.Fiks.Arkiv.Models.V1.Arkivering.Arkivmelding.Klassifikasjon>> GetCaseFileClassifications(Altinn.App.Core.Features.Auth.Authenticated auth, System.Threading.CancellationToken cancellationToken = default);
         string GetCorrelationId(Altinn.Platform.Storage.Interface.Models.Instance instance);
-        System.Threading.Tasks.Task<KS.Fiks.Arkiv.Models.V1.Arkivering.Arkivmelding.Klassifikasjon> GetInstanceOwnerClassification(Altinn.App.Core.Features.Auth.Authenticated auth, System.Threading.CancellationToken cancellationToken = default);
         System.Threading.Tasks.Task<KS.Fiks.Arkiv.Models.V1.Arkivering.Arkivmelding.Korrespondansepart?> GetInstanceOwnerParty(Altinn.Platform.Storage.Interface.Models.Instance instance, System.Threading.CancellationToken cancellationToken = default);
         System.Threading.Tasks.Task<Altinn.App.Clients.Fiks.FiksArkiv.Models.FiksArkivRecipient> GetRecipient(Altinn.Platform.Storage.Interface.Models.Instance instance, System.Threading.CancellationToken cancellationToken = default);
         KS.Fiks.Arkiv.Models.V1.Arkivering.Arkivmelding.Korrespondansepart GetRecipientParty(Altinn.Platform.Storage.Interface.Models.Instance instance, Altinn.App.Clients.Fiks.FiksArkiv.Models.FiksArkivRecipient recipient);
@@ -99,6 +99,18 @@ namespace Altinn.App.Clients.Fiks.FiksArkiv.Models
         [System.Text.Json.Serialization.JsonPropertyName("value")]
         public T Value { get; set; }
     }
+    public sealed class FiksArkivClassification : System.IEquatable<Altinn.App.Clients.Fiks.FiksArkiv.Models.FiksArkivClassification>
+    {
+        public FiksArkivClassification() { }
+        [System.Text.Json.Serialization.JsonPropertyName("classificationId")]
+        public required string ClassificationId { get; set; }
+        [System.Text.Json.Serialization.JsonPropertyName("isRestricted")]
+        public bool? IsRestricted { get; set; }
+        [System.Text.Json.Serialization.JsonPropertyName("systemId")]
+        public required string SystemId { get; set; }
+        [System.Text.Json.Serialization.JsonPropertyName("title")]
+        public required string Title { get; set; }
+    }
     public sealed class FiksArkivDataModelBinding : System.IEquatable<Altinn.App.Clients.Fiks.FiksArkiv.Models.FiksArkivDataModelBinding>
     {
         public FiksArkivDataModelBinding() { }
@@ -115,6 +127,8 @@ namespace Altinn.App.Clients.Fiks.FiksArkiv.Models
         public required string DataType { get; set; }
         [System.Text.Json.Serialization.JsonPropertyName("filename")]
         public string? Filename { get; set; }
+        [System.Text.Json.Serialization.JsonPropertyName("formatCode")]
+        public string? FormatCode { get; set; }
         public string GetFilenameOrDefault(string defaultExtension = "xml") { }
     }
     public sealed class FiksArkivDocumentMetadata : System.IEquatable<Altinn.App.Clients.Fiks.FiksArkiv.Models.FiksArkivDocumentMetadata>
@@ -145,6 +159,8 @@ namespace Altinn.App.Clients.Fiks.FiksArkiv.Models
     public sealed class FiksArkivMetadataSettings : System.IEquatable<Altinn.App.Clients.Fiks.FiksArkiv.Models.FiksArkivMetadataSettings>
     {
         public FiksArkivMetadataSettings() { }
+        [System.Text.Json.Serialization.JsonPropertyName("caseFileClassifications")]
+        public System.Collections.Generic.IReadOnlyList<Altinn.App.Clients.Fiks.FiksArkiv.Models.FiksArkivClassification>? CaseFileClassifications { get; set; }
         [System.Text.Json.Serialization.JsonPropertyName("caseFileId")]
         public Altinn.App.Clients.Fiks.FiksArkiv.Models.FiksArkivBindableValue<string>? CaseFileId { get; set; }
         [System.Text.Json.Serialization.JsonPropertyName("caseFileTitle")]