diff --git a/catalyst_voices/packages/internal/catalyst_voices_shared/lib/src/catalyst_voices_shared.dart b/catalyst_voices/packages/internal/catalyst_voices_shared/lib/src/catalyst_voices_shared.dart
index 884defba558d..0e369f46b234 100644
--- a/catalyst_voices/packages/internal/catalyst_voices_shared/lib/src/catalyst_voices_shared.dart
+++ b/catalyst_voices/packages/internal/catalyst_voices_shared/lib/src/catalyst_voices_shared.dart
@@ -7,6 +7,7 @@ export 'crypto/crypto_service.dart';
 export 'crypto/key_derivation.dart';
 export 'crypto/local_crypto_service.dart';
 export 'dependency/dependency_provider.dart';
+export 'document/document_manager.dart';
 export 'document/extension/document_list_sort_ext.dart';
 export 'document/extension/document_map_to_list_ext.dart';
 export 'document/identifiable.dart';
diff --git a/catalyst_voices/packages/internal/catalyst_voices_shared/lib/src/document/document_manager.dart b/catalyst_voices/packages/internal/catalyst_voices_shared/lib/src/document/document_manager.dart
new file mode 100644
index 000000000000..b5582446d4a2
--- /dev/null
+++ b/catalyst_voices/packages/internal/catalyst_voices_shared/lib/src/document/document_manager.dart
@@ -0,0 +1,83 @@
+import 'dart:typed_data';
+
+import 'package:catalyst_compression/catalyst_compression.dart';
+import 'package:catalyst_cose/catalyst_cose.dart';
+import 'package:catalyst_key_derivation/catalyst_key_derivation.dart';
+import 'package:cbor/cbor.dart';
+import 'package:equatable/equatable.dart';
+
+part 'document_manager_impl.dart';
+
+/// Parses the document from the bytes obtained from [BinaryDocument.toBytes].
+///
+/// Usually this would convert the [bytes] into a [String],
+/// decode a [String] into a json and then parse the data class
+/// from the json representation.
+typedef DocumentParser<T extends BinaryDocument> = T Function(Uint8List bytes);
+
+/// Manages the [SignedDocument]s.
+abstract interface class DocumentManager {
+  /// The default constructor for the [DocumentManager],
+  /// provides the default implementation of the interface.
+  const factory DocumentManager() = _DocumentManagerImpl;
+
+  /// Parses the document from the [bytes] representation.
+  ///
+  /// The [parser] must be able to parse the document
+  /// from the bytes produced by [BinaryDocument.toBytes].
+  ///
+  /// The implementation of this method must be able to understand the [bytes]
+  /// that are obtained from the [SignedDocument.toBytes] method.
+  Future<SignedDocument<T>> parseDocument<T extends BinaryDocument>(
+    Uint8List bytes, {
+    required DocumentParser<T> parser,
+  });
+
+  /// Signs the [document] with a single [privateKey].
+  ///
+  /// The [publicKey] will be added as metadata in the signed document
+  /// so that it's easier to identify who signed it.
+  Future<SignedDocument<T>> signDocument<T extends BinaryDocument>(
+    T document, {
+    required Uint8List publicKey,
+    required Uint8List privateKey,
+  });
+}
+
+/// Represents an abstract document that is protected
+/// with cryptographic signature.
+///
+/// The [document] payload can be UTF-8 encoded bytes, a binary data
+/// or anything else that can be represented in binary format.
+abstract interface class SignedDocument<T extends BinaryDocument> {
+  /// The default constructor for the [SignedDocument].
+  const SignedDocument();
+
+  /// A getter that returns a parsed document.
+  T get document;
+
+  /// Verifies if the [document] has been signed by a private key
+  /// that belongs to the given [publicKey].
+  Future<bool> verifySignature(Uint8List publicKey);
+
+  /// Converts the document into binary representation.
+  Uint8List toBytes();
+}
+
+/// Represents an abstract document that can be represented in binary format.
+// ignore: one_member_abstracts
+abstract interface class BinaryDocument {
+  /// Converts the document into a binary representation.
+  ///
+  /// See [DocumentParser].
+  Uint8List toBytes();
+
+  /// Returns the document content type.
+  DocumentContentType get contentType;
+}
+
+/// Defines the content type of the [BinaryDocument].
+enum DocumentContentType {
+  /// The document's content type is JSON.
+  json,
+}
diff --git a/catalyst_voices/packages/internal/catalyst_voices_shared/lib/src/document/document_manager_impl.dart b/catalyst_voices/packages/internal/catalyst_voices_shared/lib/src/document/document_manager_impl.dart
new file mode 100644
index 000000000000..38682442e327
--- /dev/null
+++ b/catalyst_voices/packages/internal/catalyst_voices_shared/lib/src/document/document_manager_impl.dart
@@ -0,0 +1,129 @@
+part of 'document_manager.dart';
+
+const _brotliEncoding = StringValue(CoseValues.brotliContentEncoding);
+
+final class _DocumentManagerImpl implements DocumentManager {
+  const _DocumentManagerImpl();
+
+  @override
+  Future<SignedDocument<T>> parseDocument<T extends BinaryDocument>(
+    Uint8List bytes, {
+    required DocumentParser<T> parser,
+  }) async {
+    final coseSign = CoseSign.fromCbor(cbor.decode(bytes));
+    final payload = await _brotliDecompressPayload(coseSign);
+    final document = parser(payload);
+    return _CoseSignedDocument(coseSign, document);
+  }
+
+  @override
+  Future<SignedDocument<T>> signDocument<T extends BinaryDocument>(
+    T document, {
+    required Uint8List publicKey,
+    required Uint8List privateKey,
+  }) async {
+    final compressedPayload = await _brotliCompressPayload(document.toBytes());
+
+    final coseSign = await CoseSign.sign(
+      protectedHeaders: CoseHeaders.protected(
+        contentEncoding: _brotliEncoding,
+        contentType: document.contentType.asCose,
+      ),
+      unprotectedHeaders: const CoseHeaders.unprotected(),
+      payload: compressedPayload,
+      signers: [_Bip32Ed25519XSigner(publicKey, privateKey)],
+    );
+
+    return _CoseSignedDocument(coseSign, document);
+  }
+
+  Future<Uint8List> _brotliCompressPayload(Uint8List payload) async {
+    final compressor = CatalystCompression.instance.brotli;
+    final compressed = await compressor.compress(payload);
+    return Uint8List.fromList(compressed);
+  }
+
+  Future<Uint8List> _brotliDecompressPayload(CoseSign coseSign) async {
+    if (coseSign.protectedHeaders.contentEncoding == _brotliEncoding) {
+      final compressor = CatalystCompression.instance.brotli;
+      final decompressed = await compressor.decompress(coseSign.payload);
+      return Uint8List.fromList(decompressed);
+    } else {
+      return coseSign.payload;
+    }
+  }
+}
+
+final class _CoseSignedDocument<T extends BinaryDocument>
+    extends SignedDocument<T> with EquatableMixin {
+  final CoseSign _coseSign;
+
+  @override
+  final T document;
+
+  const _CoseSignedDocument(this._coseSign, this.document);
+
+  @override
+  Future<bool> verifySignature(Uint8List publicKey) async {
+    return _coseSign.verify(
+      verifier: _Bip32Ed25519XVerifier(publicKey),
+    );
+  }
+
+  @override
+  Uint8List toBytes() {
+    final bytes = cbor.encode(_coseSign.toCbor());
+    return Uint8List.fromList(bytes);
+  }
+
+  @override
+  List<Object?> get props => [_coseSign, document];
+}
+
+extension _CoseDocumentContentType on DocumentContentType {
+  /// Maps the [DocumentContentType] into COSE representation.
+  StringOrInt get asCose {
+    switch (this) {
+      case DocumentContentType.json:
+        return const IntValue(CoseValues.jsonContentType);
+    }
+  }
+}
+
+final class _Bip32Ed25519XSigner implements CatalystCoseSigner {
+  final Uint8List publicKey;
+  final Uint8List privateKey;
+
+  const _Bip32Ed25519XSigner(this.publicKey, this.privateKey);
+
+  @override
+  StringOrInt? get alg => const IntValue(CoseValues.eddsaAlg);
+
+  @override
+  Future<Uint8List?> get kid async => publicKey;
+
+  @override
+  Future<Uint8List> sign(Uint8List data) async {
+    final pk = Bip32Ed25519XPrivateKeyFactory.instance.fromBytes(privateKey);
+    final signature = await pk.sign(data);
+    return Uint8List.fromList(signature.bytes);
+  }
+}
+
+final class _Bip32Ed25519XVerifier implements CatalystCoseVerifier {
+  final Uint8List publicKey;
+
+  const _Bip32Ed25519XVerifier(this.publicKey);
+
+  @override
+  Future<Uint8List?> get kid async => publicKey;
+
+  @override
+  Future<bool> verify(Uint8List data, Uint8List signature) async {
+    final pk = Bip32Ed25519XPublicKeyFactory.instance.fromBytes(publicKey);
+    return pk.verify(
+      data,
+      signature: Bip32Ed25519XSignatureFactory.instance.fromBytes(signature),
+    );
+  }
+}
diff --git a/catalyst_voices/packages/internal/catalyst_voices_shared/pubspec.yaml b/catalyst_voices/packages/internal/catalyst_voices_shared/pubspec.yaml
index 56bdf864fa96..14da899f7d65 100644
--- a/catalyst_voices/packages/internal/catalyst_voices_shared/pubspec.yaml
+++ b/catalyst_voices/packages/internal/catalyst_voices_shared/pubspec.yaml
@@ -9,9 +9,12 @@ environment:
 
 dependencies:
   catalyst_cardano_serialization: ^0.4.0
+  catalyst_compression: ^0.3.0
+  catalyst_cose: ^0.3.0
   catalyst_key_derivation: ^0.1.0
   catalyst_voices_models:
     path: ../catalyst_voices_models
+  cbor: ^6.2.0
   collection: ^1.18.0
   convert: ^3.1.1
   cryptography: ^2.7.0
diff --git a/catalyst_voices/packages/internal/catalyst_voices_shared/test/src/document/document_manager_test.dart b/catalyst_voices/packages/internal/catalyst_voices_shared/test/src/document/document_manager_test.dart
new file mode 100644
index 000000000000..40b1e7ff4c6d
--- /dev/null
+++ b/catalyst_voices/packages/internal/catalyst_voices_shared/test/src/document/document_manager_test.dart
@@ -0,0 +1,172 @@
+import 'dart:convert';
+
+import 'package:catalyst_compression/catalyst_compression.dart';
+import 'package:catalyst_key_derivation/catalyst_key_derivation.dart';
+import 'package:catalyst_voices_shared/src/document/document_manager.dart';
+import 'package:convert/convert.dart';
+import 'package:equatable/equatable.dart';
+import 'package:flutter/foundation.dart';
+import 'package:flutter_test/flutter_test.dart';
+
+final _privateKey = Uint8List.fromList(List.filled(32, 0));
+final _publicKey = Uint8List.fromList(List.filled(32, 1));
+final _signature = Uint8List.fromList(List.filled(32, 2));
+
+void main() {
+  group(DocumentManager, () {
+    const documentManager = DocumentManager();
+
+    setUpAll(() {
+      CatalystCompressionPlatform.instance = _FakeCatalystCompressionPlatform();
+
+      Bip32Ed25519XPublicKeyFactory.instance =
+          _FakeBip32Ed25519XPublicKeyFactory();
+
+      Bip32Ed25519XPrivateKeyFactory.instance =
+          _FakeBip32Ed25519XPrivateKeyFactory();
+
+      Bip32Ed25519XSignatureFactory.instance =
+          _FakeBip32Ed25519XSignatureFactory();
+    });
+
+    test(
+        'signDocument creates a signed document '
+        'that can be converted from/to bytes', () async {
+      const document = _JsonDocument('title');
+
+      final signedDocument = await documentManager.signDocument(
+        document,
+        publicKey: _publicKey,
+        privateKey: _privateKey,
+      );
+
+      expect(signedDocument.document, equals(document));
+
+      final isVerified = await signedDocument.verifySignature(_publicKey);
+      expect(isVerified, isTrue);
+
+      final signedDocumentBytes = signedDocument.toBytes();
+      final parsedDocument = await documentManager.parseDocument(
+        signedDocumentBytes,
+        parser: _JsonDocument.fromBytes,
+      );
+
+      expect(parsedDocument, equals(signedDocument));
+    });
+  });
+}
+
+final class _JsonDocument extends Equatable implements BinaryDocument {
+  final String title;
+
+  const _JsonDocument(this.title);
+
+  factory _JsonDocument.fromBytes(Uint8List bytes) {
+    final string = utf8.decode(bytes);
+    final map = json.decode(string);
+    return _JsonDocument.fromJson(map as Map<String, dynamic>);
+  }
+
+  factory _JsonDocument.fromJson(Map<String, dynamic> map) {
+    return _JsonDocument(map['title'] as String);
+  }
+
+  Map<String, dynamic> toJson() {
+    return {'title': title};
+  }
+
+  @override
+  Uint8List toBytes() {
+    final jsonString = json.encode(toJson());
+    return utf8.encode(jsonString);
+  }
+
+  @override
+  DocumentContentType get contentType => DocumentContentType.json;
+
+  @override
+  List<Object?> get props => [title];
+}
+
+class _FakeCatalystCompressionPlatform extends CatalystCompressionPlatform {
+  @override
+  CatalystCompressor get brotli => const _FakeCompressor();
+}
+
+final class _FakeCompressor implements CatalystCompressor {
+  const _FakeCompressor();
+
+  @override
+  Future<List<int>> compress(List<int> bytes) async => bytes;
+
+  @override
+  Future<List<int>> decompress(List<int> bytes) async => bytes;
+}
+
+class _FakeBip32Ed25519XPublicKeyFactory extends Bip32Ed25519XPublicKeyFactory {
+  @override
+  Bip32Ed25519XPublicKey fromBytes(List<int> bytes) {
+    return _FakeBip32Ed22519XPublicKey(bytes: bytes);
+  }
+}
+
+class _FakeBip32Ed25519XPrivateKeyFactory
+    extends Bip32Ed25519XPrivateKeyFactory {
+  @override
+  Bip32Ed25519XPrivateKey fromBytes(List<int> bytes) {
+    return _FakeBip32Ed22519XPrivateKey(bytes: bytes);
+  }
+}
+
+class _FakeBip32Ed25519XSignatureFactory extends Bip32Ed25519XSignatureFactory {
+  @override
+  Bip32Ed25519XSignature fromBytes(List<int> bytes) {
+    return _FakeBip32Ed22519XSignature(bytes: bytes);
+  }
+}
+
+class _FakeBip32Ed22519XPublicKey extends Fake
+    implements Bip32Ed25519XPublicKey {
+  @override
+  final List<int> bytes;
+
+  _FakeBip32Ed22519XPublicKey({required this.bytes});
+
+  @override
+  Future<bool> verify(
+    List<int> message, {
+    required Bip32Ed25519XSignature signature,
+  }) async {
+    return listEquals(signature.bytes, _signature);
+  }
+
+  @override
+  String toHex() => hex.encode(bytes);
+}
+
+class _FakeBip32Ed22519XPrivateKey extends Fake
+    implements Bip32Ed25519XPrivateKey {
+  @override
+  final List<int> bytes;
+
+  _FakeBip32Ed22519XPrivateKey({required this.bytes});
+
+  @override
+  Future<Bip32Ed25519XSignature> sign(List<int> message) async {
+    return _FakeBip32Ed22519XSignature(bytes: _signature);
+  }
+
+  @override
+  String toHex() => hex.encode(bytes);
+}
+
+class _FakeBip32Ed22519XSignature extends Fake
+    implements Bip32Ed25519XSignature {
+  @override
+  final List<int> bytes;
+
+  _FakeBip32Ed22519XSignature({required this.bytes});
+
+  @override
+  String toHex() => hex.encode(bytes);
+}
diff --git a/catalyst_voices/packages/libs/catalyst_cose/README.md b/catalyst_voices/packages/libs/catalyst_cose/README.md
index ee107be4752f..90915e7da43b 100644
--- a/catalyst_voices/packages/libs/catalyst_cose/README.md
+++ b/catalyst_voices/packages/libs/catalyst_cose/README.md
@@ -47,14 +47,10 @@ Future<void> main() async {
 Future<void> _coseSign1() async {
   final algorithm = Ed25519();
   final keyPair = await algorithm.newKeyPairFromSeed(List.filled(32, 0));
-  final publicKey = await keyPair.extractPublicKey().then((e) => e.bytes);
   final signerVerifier = _SignerVerifier(algorithm, keyPair);
 
   final coseSign1 = await CoseSign1.sign(
-    protectedHeaders: CoseHeaders.protected(
-      alg: const IntValue(CoseValues.eddsaAlg),
-      kid: hex.encode(publicKey),
-    ),
+    protectedHeaders: const CoseHeaders.protected(),
     unprotectedHeaders: const CoseHeaders.unprotected(),
     signer: signerVerifier,
     payload: utf8.encode('This is the content.'),
@@ -78,20 +74,16 @@ Future<void> _coseSign1() async {
 Future<void> _coseSign() async {
   final algorithm = Ed25519();
   final keyPair = await algorithm.newKeyPairFromSeed(List.filled(32, 0));
-  final publicKey = await keyPair.extractPublicKey().then((e) => e.bytes);
   final signerVerifier = _SignerVerifier(algorithm, keyPair);
 
   final coseSign = await CoseSign.sign(
-    protectedHeaders: CoseHeaders.protected(
-      alg: const IntValue(CoseValues.eddsaAlg),
-      kid: hex.encode(publicKey),
-    ),
+    protectedHeaders: const CoseHeaders.protected(),
     unprotectedHeaders: const CoseHeaders.unprotected(),
     signers: [signerVerifier],
     payload: utf8.encode('This is the content.'),
   );
 
-  final verified = await coseSign.verify(
+  final verified = await coseSign.verifyAll(
     verifiers: [signerVerifier],
   );
 
@@ -113,6 +105,15 @@ final class _SignerVerifier
 
   const _SignerVerifier(this._algorithm, this._keyPair);
 
+  @override
+  StringOrInt? get alg => const IntValue(CoseValues.eddsaAlg);
+
+  @override
+  Future<Uint8List?> get kid async {
+    final pk = await _keyPair.extractPublicKey();
+    return Uint8List.fromList(pk.bytes);
+  }
+
   @override
   Future<Uint8List> sign(Uint8List data) async {
     final signature = await _algorithm.sign(data, keyPair: _keyPair);
diff --git a/catalyst_voices/packages/libs/catalyst_cose/example/main.dart b/catalyst_voices/packages/libs/catalyst_cose/example/main.dart
index c7ea8131a662..3bed84f27249 100644
--- a/catalyst_voices/packages/libs/catalyst_cose/example/main.dart
+++ b/catalyst_voices/packages/libs/catalyst_cose/example/main.dart
@@ -16,14 +16,10 @@ Future<void> main() async {
 Future<void> _coseSign1() async {
   final algorithm = Ed25519();
   final keyPair = await algorithm.newKeyPairFromSeed(List.filled(32, 0));
-  final publicKey = await keyPair.extractPublicKey().then((e) => e.bytes);
   final signerVerifier = _SignerVerifier(algorithm, keyPair);
 
   final coseSign1 = await CoseSign1.sign(
-    protectedHeaders: CoseHeaders.protected(
-      alg: const IntValue(CoseValues.eddsaAlg),
-      kid: hex.encode(publicKey),
-    ),
+    protectedHeaders: const CoseHeaders.protected(),
     unprotectedHeaders: const CoseHeaders.unprotected(),
     signer: signerVerifier,
     payload: utf8.encode('This is the content.'),
@@ -47,20 +43,16 @@ Future<void> _coseSign1() async {
 Future<void> _coseSign() async {
   final algorithm = Ed25519();
   final keyPair = await algorithm.newKeyPairFromSeed(List.filled(32, 0));
-  final publicKey = await keyPair.extractPublicKey().then((e) => e.bytes);
   final signerVerifier = _SignerVerifier(algorithm, keyPair);
 
   final coseSign = await CoseSign.sign(
-    protectedHeaders: CoseHeaders.protected(
-      alg: const IntValue(CoseValues.eddsaAlg),
-      kid: hex.encode(publicKey),
-    ),
+    protectedHeaders: const CoseHeaders.protected(),
     unprotectedHeaders: const CoseHeaders.unprotected(),
     signers: [signerVerifier],
     payload: utf8.encode('This is the content.'),
   );
 
-  final verified = await coseSign.verify(
+  final verified = await coseSign.verifyAll(
     verifiers: [signerVerifier],
   );
 
@@ -82,6 +74,15 @@ final class _SignerVerifier
 
   const _SignerVerifier(this._algorithm, this._keyPair);
 
+  @override
+  StringOrInt? get alg => const IntValue(CoseValues.eddsaAlg);
+
+  @override
+  Future<Uint8List?> get kid async {
+    final pk = await _keyPair.extractPublicKey();
+    return Uint8List.fromList(pk.bytes);
+  }
+
   @override
   Future<Uint8List> sign(Uint8List data) async {
     final signature = await _algorithm.sign(data, keyPair: _keyPair);
diff --git a/catalyst_voices/packages/libs/catalyst_cose/lib/src/cose_constants.dart b/catalyst_voices/packages/libs/catalyst_cose/lib/src/cose_constants.dart
index feec000ce264..a914fd495292 100644
--- a/catalyst_voices/packages/libs/catalyst_cose/lib/src/cose_constants.dart
+++ b/catalyst_voices/packages/libs/catalyst_cose/lib/src/cose_constants.dart
@@ -1,5 +1,6 @@
 import 'dart:typed_data';
 
+import 'package:catalyst_cose/src/types/string_or_int.dart';
 import 'package:cbor/cbor.dart';
 
 /// Holds commonly used tags in COSE.
@@ -62,7 +63,7 @@ final class CoseValues {
   static const eddsaAlg = -8;
 
   /// The json content type value.
-  static const jsonContentType = 30;
+  static const jsonContentType = 50;
 
   /// The brotli compression content encoding.
   static const brotliContentEncoding = 'br';
@@ -71,6 +72,14 @@ final class CoseValues {
 /// The interface for the data signer callback.
 // ignore: one_member_abstracts
 abstract interface class CatalystCoseSigner {
+  /// Returns the alg identifier that should refer
+  /// to the cryptographic algorithm used to [sign] the data.
+  StringOrInt? get alg;
+
+  /// Returns a key identifier that typically should refer to the public key
+  /// of the private key used to sign the data.
+  Future<Uint8List?> get kid;
+
   /// The [data] should be signed with a private key
   /// and the resulting signature returned as [Uint8List].
   Future<Uint8List> sign(Uint8List data);
@@ -79,6 +88,10 @@ abstract interface class CatalystCoseSigner {
 /// The interface for the signature verifier callback.
 // ignore: one_member_abstracts
 abstract interface class CatalystCoseVerifier {
+  /// Returns a key identifier that typically should refer to the public key
+  /// of the private key used to sign the data.
+  Future<Uint8List?> get kid;
+
   /// The [signature] should be verified against
   /// a known public/private key over the [data].
   Future<bool> verify(Uint8List data, Uint8List signature);
diff --git a/catalyst_voices/packages/libs/catalyst_cose/lib/src/cose_sign.dart b/catalyst_voices/packages/libs/catalyst_cose/lib/src/cose_sign.dart
index e525fe941d87..7d73a4eaceca 100644
--- a/catalyst_voices/packages/libs/catalyst_cose/lib/src/cose_sign.dart
+++ b/catalyst_voices/packages/libs/catalyst_cose/lib/src/cose_sign.dart
@@ -3,6 +3,7 @@ import 'dart:typed_data';
 import 'package:catalyst_cose/src/cose_constants.dart';
 import 'package:catalyst_cose/src/types/cose_headers.dart';
 import 'package:cbor/cbor.dart';
+import 'package:collection/collection.dart';
 import 'package:equatable/equatable.dart';
 
 /// The COSE_SIGN structure implementation, supporting multiple signatures.
@@ -34,9 +35,7 @@ final class CoseSign extends Equatable {
 
   /// Deserializes the type from cbor.
   factory CoseSign.fromCbor(CborValue value) {
-    if (value is! CborList ||
-        value.length != 4 ||
-        !value.tags.contains(CoseTags.coseSign)) {
+    if (value is! CborList || value.length != 4) {
       throw FormatException('$value is not a valid COSE_SIGN structure');
     }
 
@@ -72,21 +71,14 @@ final class CoseSign extends Equatable {
     final signatures = <CoseSignature>[];
     for (final signer in signers) {
       final signatureProtectedHeaders = CoseHeaders.protected(
-        alg: protectedHeaders.alg,
+        alg: signer.alg,
+        kid: await signer.kid,
       );
 
-      final sigStructure = _createCoseSignSigStructure(
-        bodyProtectedHeaders: protectedHeaders.toCbor(),
-        signatureProtectedHeaders: signatureProtectedHeaders.toCbor(),
-        payload: CborBytes(payload),
-      );
-
-      final toBeSigned = Uint8List.fromList(
-        cbor.encode(
-          CborBytes(
-            cbor.encode(sigStructure),
-          ),
-        ),
+      final toBeSigned = _createCoseSignSigStructureBytes(
+        bodyProtectedHeaders: protectedHeaders,
+        signatureProtectedHeaders: signatureProtectedHeaders,
+        payload: payload,
       );
 
       final signature = CoseSignature(
@@ -106,46 +98,37 @@ final class CoseSign extends Equatable {
     );
   }
 
-  /// Verifies whether the COSE_SIGN [signatures] are valid.
+  /// Verifies whether the COSE_SIGN signature is valid.
   ///
-  /// The [verifiers] are responsible for providing the verification algorithm.
-  /// The count of [verifiers] must match the number of [signatures].
+  /// The signature is selected from the list of [signatures] based on the kid].
+  /// The [verifier] is responsible for providing the verification algorithm.
   Future<bool> verify({
-    required List<CatalystCoseVerifier> verifiers,
+    required CatalystCoseVerifier verifier,
   }) async {
-    if (verifiers.length != signatures.length) {
-      throw ArgumentError(
-        'Number of verifiers must match the number of signatures.',
-      );
+    for (final signature in signatures) {
+      if (const DeepCollectionEquality()
+          .equals(signature.protectedHeaders.kid, await verifier.kid)) {
+        final toBeSigned = _createCoseSignSigStructureBytes(
+          bodyProtectedHeaders: protectedHeaders,
+          signatureProtectedHeaders: signature.protectedHeaders,
+          payload: payload,
+        );
+        return verifier.verify(toBeSigned, signature.signature);
+      }
     }
 
-    for (var i = 0; i < verifiers.length; i++) {
-      final verifier = verifiers[i];
-      final signature = signatures[i];
-
-      final signatureProtectedHeaders = CoseHeaders.protected(
-        alg: protectedHeaders.alg,
-      );
-
-      final sigStructure = _createCoseSignSigStructure(
-        bodyProtectedHeaders: protectedHeaders.toCbor(),
-        signatureProtectedHeaders: signatureProtectedHeaders.toCbor(),
-        payload: CborBytes(payload),
-      );
-
-      final toBeSigned = Uint8List.fromList(
-        cbor.encode(
-          CborBytes(
-            cbor.encode(sigStructure),
-          ),
-        ),
-      );
-
-      final isVerified = await verifier.verify(
-        Uint8List.fromList(toBeSigned),
-        Uint8List.fromList(signature.signature),
-      );
+    // no eligible signature found that would match the kid
+    return false;
+  }
 
+  /// Verifies whether the COSE_SIGN [signatures] are valid.
+  ///
+  /// The [verifiers] are responsible for providing the verification algorithm.
+  Future<bool> verifyAll({
+    required List<CatalystCoseVerifier> verifiers,
+  }) async {
+    for (final verifier in verifiers) {
+      final isVerified = await verify(verifier: verifier);
       if (!isVerified) {
         return false;
       }
@@ -177,6 +160,26 @@ final class CoseSign extends Equatable {
         signatures,
       ];
 
+  static Uint8List _createCoseSignSigStructureBytes({
+    required CoseHeaders bodyProtectedHeaders,
+    required CoseHeaders signatureProtectedHeaders,
+    required Uint8List payload,
+  }) {
+    final sigStructure = _createCoseSignSigStructure(
+      bodyProtectedHeaders: bodyProtectedHeaders.toCbor(),
+      signatureProtectedHeaders: signatureProtectedHeaders.toCbor(),
+      payload: CborBytes(payload),
+    );
+
+    return Uint8List.fromList(
+      cbor.encode(
+        CborBytes(
+          cbor.encode(sigStructure),
+        ),
+      ),
+    );
+  }
+
   static CborList _createCoseSignSigStructure({
     required CborValue bodyProtectedHeaders,
     required CborValue signatureProtectedHeaders,
diff --git a/catalyst_voices/packages/libs/catalyst_cose/lib/src/cose_sign1.dart b/catalyst_voices/packages/libs/catalyst_cose/lib/src/cose_sign1.dart
index 543494882424..842fa57ef5f9 100644
--- a/catalyst_voices/packages/libs/catalyst_cose/lib/src/cose_sign1.dart
+++ b/catalyst_voices/packages/libs/catalyst_cose/lib/src/cose_sign1.dart
@@ -32,9 +32,7 @@ final class CoseSign1 extends Equatable {
 
   /// Deserializes the type from cbor.
   factory CoseSign1.fromCbor(CborValue value) {
-    if (value is! CborList ||
-        value.length != 4 ||
-        !value.tags.contains(CoseTags.coseSign1)) {
+    if (value is! CborList || value.length != 4) {
       throw FormatException('$value is not a valid COSE_SIGN1 structure');
     }
 
@@ -67,6 +65,13 @@ final class CoseSign1 extends Equatable {
     required Uint8List payload,
     required CatalystCoseSigner signer,
   }) async {
+    final kid = await signer.kid;
+
+    protectedHeaders = protectedHeaders.copyWith(
+      alg: () => signer.alg,
+      kid: () => kid,
+    );
+
     final sigStructure = _createCoseSign1SigStructure(
       protectedHeader: protectedHeaders.toCbor(),
       payload: CborBytes(payload),
diff --git a/catalyst_voices/packages/libs/catalyst_cose/lib/src/types/cose_headers.dart b/catalyst_voices/packages/libs/catalyst_cose/lib/src/types/cose_headers.dart
index dbc93956577f..ff1da58c1133 100644
--- a/catalyst_voices/packages/libs/catalyst_cose/lib/src/types/cose_headers.dart
+++ b/catalyst_voices/packages/libs/catalyst_cose/lib/src/types/cose_headers.dart
@@ -1,3 +1,5 @@
+import 'dart:typed_data';
+
 import 'package:catalyst_cose/src/cose_constants.dart';
 import 'package:catalyst_cose/src/types/string_or_int.dart';
 import 'package:catalyst_cose/src/types/uuid.dart';
@@ -5,14 +7,27 @@ import 'package:catalyst_cose/src/utils/cbor_utils.dart';
 import 'package:cbor/cbor.dart';
 import 'package:equatable/equatable.dart';
 
+/// A callback to get an optional value.
+/// Helps to distinguish whether a method argument
+/// has been passed as null or not passed at all.
+///
+/// See [CoseHeaders.copyWith].
+typedef OptionalValueGetter<T> = T? Function();
+
 /// A class that specifies headers that
 /// can be used in protected/unprotected COSE headers.
 final class CoseHeaders extends Equatable {
   /// See [CoseHeaderKeys.alg].
+  ///
+  /// Do not set the [alg] directly in the headers,
+  /// it will be auto-populated with [CatalystCoseSigner.alg] value.
   final StringOrInt? alg;
 
   /// See [CoseHeaderKeys.kid].
-  final String? kid;
+  ///
+  /// Do not set the [kid] directly in the headers,
+  /// it will be auto-populated with [CatalystCoseSigner.kid] value.
+  final Uint8List? kid;
 
   /// See [CoseHeaderKeys.contentType].
   final StringOrInt? contentType;
@@ -116,7 +131,7 @@ final class CoseHeaders extends Equatable {
 
     return CoseHeaders(
       alg: CborUtils.deserializeStringOrInt(map[CoseHeaderKeys.alg]),
-      kid: CborUtils.deserializeString(map[CoseHeaderKeys.kid]),
+      kid: CborUtils.deserializeBytes(map[CoseHeaderKeys.kid]),
       contentType:
           CborUtils.deserializeStringOrInt(map[CoseHeaderKeys.contentType]),
       contentEncoding:
@@ -138,7 +153,7 @@ final class CoseHeaders extends Equatable {
   CborValue toCbor() {
     final map = CborMap({
       if (alg != null) CoseHeaderKeys.alg: alg!.toCbor(),
-      if (kid != null) CoseHeaderKeys.kid: CborString(kid!),
+      if (kid != null) CoseHeaderKeys.kid: CborBytes(kid!),
       if (contentType != null)
         CoseHeaderKeys.contentType: contentType!.toCbor(),
       if (contentEncoding != null)
@@ -161,6 +176,40 @@ final class CoseHeaders extends Equatable {
     }
   }
 
+  /// Returns a copy of the [CoseHeaders] with overwritten properties.
+  CoseHeaders copyWith({
+    OptionalValueGetter<StringOrInt?>? alg,
+    OptionalValueGetter<Uint8List?>? kid,
+    OptionalValueGetter<StringOrInt?>? contentType,
+    OptionalValueGetter<StringOrInt?>? contentEncoding,
+    OptionalValueGetter<Uuid?>? type,
+    OptionalValueGetter<Uuid?>? id,
+    OptionalValueGetter<Uuid?>? ver,
+    OptionalValueGetter<ReferenceUuid?>? ref,
+    OptionalValueGetter<ReferenceUuid?>? template,
+    OptionalValueGetter<ReferenceUuid?>? reply,
+    OptionalValueGetter<String?>? section,
+    OptionalValueGetter<List<String>?>? collabs,
+    bool? encodeAsBytes,
+  }) {
+    return CoseHeaders(
+      alg: alg != null ? alg() : this.alg,
+      kid: kid != null ? kid() : this.kid,
+      contentType: contentType != null ? contentType() : this.contentType,
+      contentEncoding:
+          contentEncoding != null ? contentEncoding() : this.contentEncoding,
+      type: type != null ? type() : this.type,
+      id: id != null ? id() : this.id,
+      ver: ver != null ? ver() : this.ver,
+      ref: ref != null ? ref() : this.ref,
+      template: template != null ? template() : this.template,
+      reply: reply != null ? reply() : this.reply,
+      section: section != null ? section() : this.section,
+      collabs: collabs != null ? collabs() : this.collabs,
+      encodeAsBytes: encodeAsBytes ?? this.encodeAsBytes,
+    );
+  }
+
   @override
   List<Object?> get props => [
         alg,
diff --git a/catalyst_voices/packages/libs/catalyst_cose/lib/src/types/uuid.dart b/catalyst_voices/packages/libs/catalyst_cose/lib/src/types/uuid.dart
index 927a7ce35409..14ee6c340978 100644
--- a/catalyst_voices/packages/libs/catalyst_cose/lib/src/types/uuid.dart
+++ b/catalyst_voices/packages/libs/catalyst_cose/lib/src/types/uuid.dart
@@ -10,7 +10,7 @@ import 'package:uuid/uuid.dart' as uuid;
 extension type const Uuid(String value) {
   /// Deserializes the type from cbor.
   factory Uuid.fromCbor(CborValue value) {
-    if (value is CborBytes && value.tags.contains(CborUtils.uuidTag)) {
+    if (value is CborBytes) {
       return Uuid(uuid.Uuid.unparse(value.bytes));
     } else {
       throw FormatException('The $value is not a valid uuid!');
@@ -24,80 +24,51 @@ extension type const Uuid(String value) {
   }
 }
 
-/// Either a single [Uuid] or two [Uuid]'s.
+/// A reference to an entity represented by the [id].
+/// Optionally the version of the entity may be specified by the [ver].
 ///
 /// What this uuid means depends where and how the class is used.
 /// In CDDL it is defined as (UUID / [UUID, UUID]).
-sealed class ReferenceUuid extends Equatable {
+final class ReferenceUuid extends Equatable {
+  /// The referenced entity uuid.
+  final Uuid id;
+
+  /// The version of the referenced entity.
+  final Uuid? ver;
+
   /// The default constructor for the [ReferenceUuid].
-  const ReferenceUuid();
+  const ReferenceUuid({
+    required this.id,
+    this.ver,
+  });
 
   /// Deserializes the type from cbor.
   factory ReferenceUuid.fromCbor(CborValue value) {
     if (value is CborList) {
-      return DoubleReferenceUuid.fromCbor(value);
+      return ReferenceUuid(
+        id: Uuid.fromCbor(value[0]),
+        ver: Uuid.fromCbor(value[1]),
+      );
     } else {
-      return SingleReferenceUuid.fromCbor(value);
+      return ReferenceUuid(
+        id: Uuid.fromCbor(value),
+      );
     }
   }
 
   /// Serializes the type as cbor.
-  CborValue toCbor();
-}
-
-/// A single [Uuid] reference.
-final class SingleReferenceUuid extends ReferenceUuid {
-  /// A single reference uuid.
-  final Uuid uuid;
-
-  /// A default constructor for the [SingleReferenceUuid].
-  const SingleReferenceUuid(this.uuid);
-
-  /// Deserializes the type from cbor.
-  factory SingleReferenceUuid.fromCbor(CborValue value) {
-    return SingleReferenceUuid(Uuid.fromCbor(value));
-  }
-
-  @override
   CborValue toCbor() {
-    return uuid.toCbor();
-  }
-
-  @override
-  List<Object?> get props => [uuid];
-}
-
-/// A single [Uuid] reference.
-final class DoubleReferenceUuid extends ReferenceUuid {
-  /// The first referenced uuid.
-  final Uuid first;
-
-  /// The second reference uuid.
-  final Uuid second;
-
-  /// A default constructor for the [DoubleReferenceUuid].
-  const DoubleReferenceUuid(this.first, this.second);
-
-  /// Deserializes the type from cbor.
-  factory DoubleReferenceUuid.fromCbor(CborValue value) {
-    if (value is! CborList || value.length != 2) {
-      throw FormatException('Wrong format of the DoubleReferenceUuid: $value');
+    final ver = this.ver;
+    if (ver != null) {
+      return CborList([
+        id.toCbor(),
+        ver.toCbor(),
+      ]);
+    } else {
+      return id.toCbor();
     }
-
-    return DoubleReferenceUuid(
-      Uuid.fromCbor(value[0]),
-      Uuid.fromCbor(value[1]),
-    );
-  }
-
-  @override
-  CborValue toCbor() {
-    return CborList([
-      first.toCbor(),
-      second.toCbor(),
-    ]);
   }
 
   @override
-  List<Object?> get props => [first, second];
+  List<Object?> get props => [id, ver];
 }
diff --git a/catalyst_voices/packages/libs/catalyst_cose/lib/src/utils/cbor_utils.dart b/catalyst_voices/packages/libs/catalyst_cose/lib/src/utils/cbor_utils.dart
index a3e5b9f80fe6..969b38f545c0 100644
--- a/catalyst_voices/packages/libs/catalyst_cose/lib/src/utils/cbor_utils.dart
+++ b/catalyst_voices/packages/libs/catalyst_cose/lib/src/utils/cbor_utils.dart
@@ -1,3 +1,6 @@
+import 'dart:convert';
+import 'dart:typed_data';
+
 import 'package:catalyst_cose/src/types/string_or_int.dart';
 import 'package:catalyst_cose/src/types/uuid.dart';
 import 'package:cbor/cbor.dart';
@@ -36,6 +39,19 @@ final class CborUtils {
     return ReferenceUuid.fromCbor(value);
   }
 
+  /// Deserializes optional [Uint8List] type.
+  static Uint8List? deserializeBytes(CborValue? value) {
+    if (value == null) {
+      return null;
+    }
+
+    if (value is CborString) {
+      return utf8.encode(value.toString());
+    }
+
+    return Uint8List.fromList((value as CborBytes).bytes);
+  }
+
   /// Deserializes optional [String] type.
   static String? deserializeString(CborValue? value) {
     if (value == null) {
diff --git a/catalyst_voices/packages/libs/catalyst_cose/pubspec.yaml b/catalyst_voices/packages/libs/catalyst_cose/pubspec.yaml
index 9f4b358988e6..6bebbcbdc825 100644
--- a/catalyst_voices/packages/libs/catalyst_cose/pubspec.yaml
+++ b/catalyst_voices/packages/libs/catalyst_cose/pubspec.yaml
@@ -10,6 +10,7 @@ environment:
 
 dependencies:
   cbor: ^6.2.0
+  collection: ^1.18.0
   convert: ^3.1.1
   cryptography: ^2.7.0
   equatable: ^2.0.7
diff --git a/catalyst_voices/packages/libs/catalyst_cose/test/cose_sign1_test.dart b/catalyst_voices/packages/libs/catalyst_cose/test/cose_sign1_test.dart
index 2273a8c0d360..83d879725751 100644
--- a/catalyst_voices/packages/libs/catalyst_cose/test/cose_sign1_test.dart
+++ b/catalyst_voices/packages/libs/catalyst_cose/test/cose_sign1_test.dart
@@ -2,45 +2,44 @@ import 'dart:convert';
 import 'dart:typed_data';
 
 import 'package:catalyst_cose/catalyst_cose.dart';
-import 'package:convert/convert.dart';
 import 'package:cryptography/cryptography.dart';
 import 'package:test/test.dart';
 
 void main() {
   group(CoseSign1, () {
     const uuidV7 = '0193b535-7196-7cd1-84e6-ad9c316cf2d2';
-    late SimplePublicKey publicKey;
     late _SignerVerifier signerVerifier;
 
     setUp(() async {
       // Initialize the Ed25519 algorithm and generate a key pair
       final algorithm = Ed25519();
       final keyPair = await algorithm.newKeyPairFromSeed(List.filled(32, 0));
-      publicKey = await keyPair.extractPublicKey();
       signerVerifier = _SignerVerifier(algorithm, keyPair);
     });
 
     test('sign generates a valid COSE_SIGN1 structure', () async {
       final coseSign1 = await CoseSign1.sign(
-        protectedHeaders: CoseHeaders.protected(
-          alg: const IntValue(CoseValues.eddsaAlg),
-          kid: hex.encode(publicKey.bytes),
-          contentType: const IntValue(CoseValues.jsonContentType),
-          contentEncoding: const StringValue(CoseValues.brotliContentEncoding),
-          type: const Uuid(uuidV7),
-          id: const Uuid(uuidV7),
-          ver: const Uuid(uuidV7),
-          ref: const SingleReferenceUuid(Uuid(uuidV7)),
-          template: const SingleReferenceUuid(Uuid(uuidV7)),
-          reply: const SingleReferenceUuid(Uuid(uuidV7)),
+        protectedHeaders: const CoseHeaders.protected(
+          contentType: IntValue(CoseValues.jsonContentType),
+          contentEncoding: StringValue(CoseValues.brotliContentEncoding),
+          type: Uuid(uuidV7),
+          id: Uuid(uuidV7),
+          ver: Uuid(uuidV7),
+          ref: ReferenceUuid(id: Uuid(uuidV7)),
+          template: ReferenceUuid(id: Uuid(uuidV7)),
+          reply: ReferenceUuid(id: Uuid(uuidV7)),
           section: 'section_name',
-          collabs: const ['test@domain.com'],
+          collabs: ['test@domain.com'],
         ),
         unprotectedHeaders: const CoseHeaders.unprotected(),
         signer: signerVerifier,
         payload: utf8.encode('Test payload'),
       );
 
+      // verify whether alg & kid fields were added to protected headers
+      expect(coseSign1.protectedHeaders.alg, isNotNull);
+      expect(coseSign1.protectedHeaders.kid, isNotEmpty);
+
       // test whether signature is valid
       final isValid = await coseSign1.verify(verifier: signerVerifier);
       expect(isValid, isTrue);
@@ -59,7 +58,7 @@ void main() {
         signature: Uint8List(64),
       );
 
-      // test whether signature is valid
+      // test whether signature is invalid
       final isValid = await coseSign1.verify(verifier: signerVerifier);
       expect(isValid, isFalse);
     });
@@ -73,6 +72,15 @@ final class _SignerVerifier
 
   const _SignerVerifier(this._algorithm, this._keyPair);
 
+  @override
+  StringOrInt? get alg => const IntValue(CoseValues.eddsaAlg);
+
+  @override
+  Future<Uint8List?> get kid async {
+    final pk = await _keyPair.extractPublicKey();
+    return Uint8List.fromList(pk.bytes);
+  }
+
   @override
   Future<Uint8List> sign(Uint8List data) async {
     final signature = await _algorithm.sign(data, keyPair: _keyPair);
diff --git a/catalyst_voices/packages/libs/catalyst_cose/test/cose_sign_test.dart b/catalyst_voices/packages/libs/catalyst_cose/test/cose_sign_test.dart
index 296415509338..2acf3925f78d 100644
--- a/catalyst_voices/packages/libs/catalyst_cose/test/cose_sign_test.dart
+++ b/catalyst_voices/packages/libs/catalyst_cose/test/cose_sign_test.dart
@@ -2,47 +2,52 @@ import 'dart:convert';
 import 'dart:typed_data';
 
 import 'package:catalyst_cose/catalyst_cose.dart';
-import 'package:convert/convert.dart';
 import 'package:cryptography/cryptography.dart';
 import 'package:test/test.dart';
 
 void main() {
   group(CoseSign, () {
+    const uuidV4 = 'e9aba14f-d05b-49b2-b5b5-100595853384';
     const uuidV7 = '0193b535-7196-7cd1-84e6-ad9c316cf2d2';
-    late SimplePublicKey publicKey;
     late _SignerVerifier signerVerifier;
 
     setUp(() async {
       // Initialize the Ed25519 algorithm and generate a key pair
       final algorithm = Ed25519();
       final keyPair = await algorithm.newKeyPairFromSeed(List.filled(32, 0));
-      publicKey = await keyPair.extractPublicKey();
       signerVerifier = _SignerVerifier(algorithm, keyPair);
     });
 
     test('sign generates a valid COSE_SIGN structure', () async {
       final coseSign = await CoseSign.sign(
-        protectedHeaders: CoseHeaders.protected(
-          alg: const IntValue(CoseValues.eddsaAlg),
-          kid: hex.encode(publicKey.bytes),
-          contentType: const IntValue(CoseValues.jsonContentType),
-          contentEncoding: const StringValue(CoseValues.brotliContentEncoding),
-          type: const Uuid(uuidV7),
-          id: const Uuid(uuidV7),
-          ver: const Uuid(uuidV7),
-          ref: const SingleReferenceUuid(Uuid(uuidV7)),
-          template: const SingleReferenceUuid(Uuid(uuidV7)),
-          reply: const SingleReferenceUuid(Uuid(uuidV7)),
+        protectedHeaders: const CoseHeaders.protected(
+          contentType: IntValue(CoseValues.jsonContentType),
+          contentEncoding: StringValue(CoseValues.brotliContentEncoding),
+          type: Uuid(uuidV4),
+          id: Uuid(uuidV7),
+          ver: Uuid(uuidV7),
+          ref: ReferenceUuid(id: Uuid(uuidV7)),
+          template: ReferenceUuid(id: Uuid(uuidV7)),
+          reply: ReferenceUuid(id: Uuid(uuidV7)),
           section: 'section_name',
-          collabs: const ['test@domain.com'],
+          collabs: ['test@domain.com'],
         ),
         unprotectedHeaders: const CoseHeaders.unprotected(),
         signers: [signerVerifier],
         payload: utf8.encode('Test payload'),
       );
 
-      // test whether signature is valid
-      final isValid = await coseSign.verify(verifiers: [signerVerifier]);
+      for (final signature in coseSign.signatures) {
+        // verify whether alg & kid fields were added to protected headers
+        expect(signature.protectedHeaders.alg, isNotNull);
+        expect(signature.protectedHeaders.kid, isNotEmpty);
+      }
+
+      // test whether signatures are valid
+      final isValidAll = await coseSign.verifyAll(verifiers: [signerVerifier]);
+      expect(isValidAll, isTrue);
+
+      final isValid = await coseSign.verify(verifier: signerVerifier);
       expect(isValid, isTrue);
 
       // test whether serialization/deserialization works
@@ -65,8 +70,12 @@ void main() {
         ],
       );
 
-      // test whether signature is valid
-      final isValid = await coseSign.verify(verifiers: [signerVerifier]);
+      // test whether all signatures are invalid
+      final isValidAll = await coseSign.verifyAll(verifiers: [signerVerifier]);
+      expect(isValidAll, isFalse);
+
+      // test whether all signatures are invalid
+      final isValid = await coseSign.verify(verifier: signerVerifier);
       expect(isValid, isFalse);
     });
   });
@@ -79,6 +88,15 @@ final class _SignerVerifier
 
   const _SignerVerifier(this._algorithm, this._keyPair);
 
+  @override
+  StringOrInt? get alg => const IntValue(CoseValues.eddsaAlg);
+
+  @override
+  Future<Uint8List?> get kid async {
+    final pk = await _keyPair.extractPublicKey();
+    return Uint8List.fromList(pk.bytes);
+  }
+
   @override
   Future<Uint8List> sign(Uint8List data) async {
     final signature = await _algorithm.sign(data, keyPair: _keyPair);