diff --git a/src/Microsoft.IdentityModel.JsonWebTokens/Json/JsonWebToken.HeaderClaimSet.cs b/src/Microsoft.IdentityModel.JsonWebTokens/Json/JsonWebToken.HeaderClaimSet.cs
index 1c8bcc20aa..0f40a709ba 100644
--- a/src/Microsoft.IdentityModel.JsonWebTokens/Json/JsonWebToken.HeaderClaimSet.cs
+++ b/src/Microsoft.IdentityModel.JsonWebTokens/Json/JsonWebToken.HeaderClaimSet.cs
@@ -13,17 +13,17 @@ public partial class JsonWebToken
     {
         internal JsonClaimSet CreateHeaderClaimSet(byte[] bytes)
         {
-            return CreateHeaderClaimSet(bytes.AsSpan());
+            return CreateHeaderClaimSet(bytes.AsMemory());
         }
 
         internal JsonClaimSet CreateHeaderClaimSet(byte[] bytes, int length)
         {
-            return CreateHeaderClaimSet(bytes.AsSpan(0, length));
+            return CreateHeaderClaimSet(bytes.AsMemory(0, length));
         }
 
-        internal JsonClaimSet CreateHeaderClaimSet(ReadOnlySpan<byte> byteSpan)
-        { 
-            Utf8JsonReader reader = new(byteSpan);
+        internal JsonClaimSet CreateHeaderClaimSet(Memory<byte> tokenHeaderAsMemory)
+        {
+            Utf8JsonReader reader = new(tokenHeaderAsMemory.Span);
             if (!JsonSerializerPrimitives.IsReaderAtTokenType(ref reader, JsonTokenType.StartObject, true))
                 throw LogHelper.LogExceptionMessage(
                     new JsonException(
@@ -36,46 +36,19 @@ internal JsonClaimSet CreateHeaderClaimSet(ReadOnlySpan<byte> byteSpan)
                         LogHelper.MarkAsNonPII(reader.CurrentDepth),
                         LogHelper.MarkAsNonPII(reader.BytesConsumed))));
 
-            Dictionary<string, object> claims = new();
+            Dictionary<string, object> claims = [];
+#if NET8_0_OR_GREATER
+            Dictionary<string, (int startIndex, int length)?> claimsBytes = [];
+#endif
             while (true)
             {
                 if (reader.TokenType == JsonTokenType.PropertyName)
                 {
-                    if (reader.ValueTextEquals(JwtHeaderUtf8Bytes.Alg))
-                    {
-                        _alg = JsonSerializerPrimitives.ReadString(ref reader, JwtHeaderParameterNames.Alg, ClassName, true);
-                        claims[JwtHeaderParameterNames.Alg] = _alg;
-                    }
-                    else if (reader.ValueTextEquals(JwtHeaderUtf8Bytes.Cty))
-                    {
-                        _cty = JsonSerializerPrimitives.ReadString(ref reader, JwtHeaderParameterNames.Cty, ClassName, true);
-                        claims[JwtHeaderParameterNames.Cty] = _cty;
-                    }
-                    else if (reader.ValueTextEquals(JwtHeaderUtf8Bytes.Kid))
-                    {
-                        _kid = JsonSerializerPrimitives.ReadString(ref reader, JwtHeaderParameterNames.Kid, ClassName, true);
-                        claims[JwtHeaderParameterNames.Kid] = _kid;
-                    }
-                    else if (reader.ValueTextEquals(JwtHeaderUtf8Bytes.Typ))
-                    {
-                        _typ = JsonSerializerPrimitives.ReadString(ref reader, JwtHeaderParameterNames.Typ, ClassName, true);
-                        claims[JwtHeaderParameterNames.Typ] = _typ;
-                    }
-                    else if (reader.ValueTextEquals(JwtHeaderUtf8Bytes.X5t))
-                    {
-                        _x5t = JsonSerializerPrimitives.ReadString(ref reader, JwtHeaderParameterNames.X5t, ClassName, true);
-                        claims[JwtHeaderParameterNames.X5t] = _x5t;
-                    }
-                    else if (reader.ValueTextEquals(JwtHeaderUtf8Bytes.Zip))
-                    {
-                        _zip = JsonSerializerPrimitives.ReadString(ref reader, JwtHeaderParameterNames.Zip, ClassName, true);
-                        claims[JwtHeaderParameterNames.Zip] = _zip;
-                    }
-                    else
-                    {
-                        string propertyName = reader.GetString();
-                        claims[propertyName] = JsonSerializerPrimitives.ReadPropertyValueAsObject(ref reader, propertyName, JsonClaimSet.ClassName, true);
-                    }
+#if NET8_0_OR_GREATER
+                    ReadHeaderValue(ref reader, claims, claimsBytes, tokenHeaderAsMemory);
+#else
+                    ReadHeaderValue(ref reader, claims);
+#endif
                 }
                 // We read a JsonTokenType.StartObject above, exiting and positioning reader at next token.
                 else if (JsonSerializerPrimitives.IsReaderAtTokenType(ref reader, JsonTokenType.EndObject, false))
@@ -84,7 +57,94 @@ internal JsonClaimSet CreateHeaderClaimSet(ReadOnlySpan<byte> byteSpan)
                     break;
             };
 
+#if NET8_0_OR_GREATER
+            return new JsonClaimSet(claims, claimsBytes, tokenHeaderAsMemory);
+#else
             return new JsonClaimSet(claims);
+#endif
+        }
+
+        private protected virtual void ReadHeaderValue(ref Utf8JsonReader reader, IDictionary<string, object> claims)
+        {
+            _ = claims ?? throw LogHelper.LogArgumentNullException(nameof(claims));
+
+            if (reader.ValueTextEquals(JwtHeaderUtf8Bytes.Alg))
+            {
+                _alg = JsonSerializerPrimitives.ReadString(ref reader, JwtHeaderParameterNames.Alg, ClassName, true);
+                claims[JwtHeaderParameterNames.Alg] = _alg;
+            }
+            else if (reader.ValueTextEquals(JwtHeaderUtf8Bytes.Cty))
+            {
+                _cty = JsonSerializerPrimitives.ReadString(ref reader, JwtHeaderParameterNames.Cty, ClassName, true);
+                claims[JwtHeaderParameterNames.Cty] = _cty;
+            }
+            else if (reader.ValueTextEquals(JwtHeaderUtf8Bytes.Kid))
+            {
+                _kid = JsonSerializerPrimitives.ReadString(ref reader, JwtHeaderParameterNames.Kid, ClassName, true);
+                claims[JwtHeaderParameterNames.Kid] = _kid;
+            }
+            else if (reader.ValueTextEquals(JwtHeaderUtf8Bytes.Typ))
+            {
+                _typ = JsonSerializerPrimitives.ReadString(ref reader, JwtHeaderParameterNames.Typ, ClassName, true);
+                claims[JwtHeaderParameterNames.Typ] = _typ;
+            }
+            else if (reader.ValueTextEquals(JwtHeaderUtf8Bytes.X5t))
+            {
+                _x5t = JsonSerializerPrimitives.ReadString(ref reader, JwtHeaderParameterNames.X5t, ClassName, true);
+                claims[JwtHeaderParameterNames.X5t] = _x5t;
+            }
+            else if (reader.ValueTextEquals(JwtHeaderUtf8Bytes.Zip))
+            {
+                _zip = JsonSerializerPrimitives.ReadString(ref reader, JwtHeaderParameterNames.Zip, ClassName, true);
+                claims[JwtHeaderParameterNames.Zip] = _zip;
+            }
+            else
+            {
+                string propertyName = reader.GetString();
+                claims[propertyName] = JsonSerializerPrimitives.ReadPropertyValueAsObject(ref reader, propertyName, JsonClaimSet.ClassName, true);
+            }
+        }
+
+#if NET8_0_OR_GREATER
+        private protected virtual void ReadHeaderValue(
+            ref Utf8JsonReader reader,
+            Dictionary<string, object> claims,
+            Dictionary<string, (int startIndex, int length)?> claimsBytes,
+            Memory<byte> tokenAsMemory)
+        {
+            _ = claims ?? throw LogHelper.LogArgumentNullException(nameof(claims));
+            _ = claimsBytes ?? throw LogHelper.LogArgumentNullException(nameof(claimsBytes));
+
+            if (reader.ValueTextEquals(JwtHeaderUtf8Bytes.Alg))
+            {
+                claimsBytes[JwtHeaderParameterNames.Alg] = JsonSerializerPrimitives.ReadStringBytesLocation(ref reader, tokenAsMemory, JwtRegisteredClaimNames.Alg, ClassName, true);
+            }
+            else if (reader.ValueTextEquals(JwtHeaderUtf8Bytes.Cty))
+            {
+                claimsBytes[JwtHeaderParameterNames.Cty] = JsonSerializerPrimitives.ReadStringBytesLocation(ref reader, tokenAsMemory, JwtHeaderParameterNames.Cty, ClassName, true);
+            }
+            else if (reader.ValueTextEquals(JwtHeaderUtf8Bytes.Kid))
+            {
+                claimsBytes[JwtHeaderParameterNames.Kid] = JsonSerializerPrimitives.ReadStringBytesLocation(ref reader, tokenAsMemory, JwtHeaderParameterNames.Kid, ClassName, true);
+            }
+            else if (reader.ValueTextEquals(JwtHeaderUtf8Bytes.Typ))
+            {
+                claimsBytes[JwtHeaderParameterNames.Typ] = JsonSerializerPrimitives.ReadStringBytesLocation(ref reader, tokenAsMemory, JwtHeaderParameterNames.Typ, ClassName, true);
+            }
+            else if (reader.ValueTextEquals(JwtHeaderUtf8Bytes.X5t))
+            {
+                claimsBytes[JwtHeaderParameterNames.X5t] = JsonSerializerPrimitives.ReadStringBytesLocation(ref reader, tokenAsMemory, JwtHeaderParameterNames.X5t, ClassName, true);
+            }
+            else if (reader.ValueTextEquals(JwtHeaderUtf8Bytes.Zip))
+            {
+                claimsBytes[JwtHeaderParameterNames.Zip] = JsonSerializerPrimitives.ReadStringBytesLocation(ref reader, tokenAsMemory, JwtHeaderParameterNames.Zip, ClassName, true);
+            }
+            else
+            {
+                string propertyName = reader.GetString();
+                claims[propertyName] = JsonSerializerPrimitives.ReadPropertyValueAsObject(ref reader, propertyName, JsonClaimSet.ClassName, true);
+            }
         }
+#endif
     }
 }
diff --git a/src/Microsoft.IdentityModel.JsonWebTokens/Json/JsonWebToken.PayloadClaimSet.cs b/src/Microsoft.IdentityModel.JsonWebTokens/Json/JsonWebToken.PayloadClaimSet.cs
index 20f9fe8dd4..87d594b7c2 100644
--- a/src/Microsoft.IdentityModel.JsonWebTokens/Json/JsonWebToken.PayloadClaimSet.cs
+++ b/src/Microsoft.IdentityModel.JsonWebTokens/Json/JsonWebToken.PayloadClaimSet.cs
@@ -62,6 +62,8 @@ internal JsonClaimSet CreatePayloadClaimSet(Memory<byte> tokenPayloadAsMemory)
 
         private protected virtual void ReadPayloadValue(ref Utf8JsonReader reader, IDictionary<string, object> claims)
         {
+            _ = claims ?? throw LogHelper.LogArgumentNullException(nameof(claims));
+
             if (reader.ValueTextEquals(JwtPayloadUtf8Bytes.Aud))
             {
                 _audiences = [];
@@ -136,6 +138,9 @@ private protected virtual void ReadPayloadValue(
             Dictionary<string, (int startIndex, int length)?> claimsBytes,
             Memory<byte> tokenAsMemory)
         {
+            _ = claims ?? throw LogHelper.LogArgumentNullException(nameof(claims));
+            _ = claimsBytes ?? throw LogHelper.LogArgumentNullException(nameof(claimsBytes));
+
             if (reader.ValueTextEquals(JwtPayloadUtf8Bytes.Aud))
             {
                 _audiences = [];
diff --git a/src/Microsoft.IdentityModel.JsonWebTokens/JsonWebToken.cs b/src/Microsoft.IdentityModel.JsonWebTokens/JsonWebToken.cs
index 0c9c5291fc..daecc01458 100644
--- a/src/Microsoft.IdentityModel.JsonWebTokens/JsonWebToken.cs
+++ b/src/Microsoft.IdentityModel.JsonWebTokens/JsonWebToken.cs
@@ -503,7 +503,7 @@ internal void ReadToken(ReadOnlyMemory<char> encodedTokenMemory)
 
                 try
                 {
-                    Header = CreateHeaderClaimSet(Base64UrlEncoder.Decode(headerSpan).AsSpan());
+                    Header = CreateHeaderClaimSet(Base64UrlEncoder.Decode(headerSpan).AsMemory());
                 }
                 catch (Exception ex)
                 {
@@ -572,7 +572,7 @@ internal JsonClaimSet CreateClaimSet(ReadOnlySpan<char> strSpan, int startIndex,
 
             byte[] output = new byte[outputSize];
             Base64UrlEncoder.Decode(strSpan.Slice(startIndex, length), output);
-            return createHeaderClaimSet ? CreateHeaderClaimSet(output.AsSpan()) : CreatePayloadClaimSet(output.AsMemory());
+            return createHeaderClaimSet ? CreateHeaderClaimSet(output.AsMemory()) : CreatePayloadClaimSet(output.AsMemory());
         }
 
         /// <summary>
@@ -1129,64 +1129,43 @@ internal DateTime? ValidToNullable
         }
         #endregion
 
-        #region Payload Properties Bytes
 #if NET8_0_OR_GREATER
 
-        /// <summary>
-        /// Gets the 'azp' claim from the payload.
-        /// </summary>
-        /// <remarks>
-        /// Identifies the authorized party for the id_token.
-        /// see: https://openid.net/specs/openid-connect-core-1_0.html
-        /// <para>
-        /// If the 'azp' claim is not found, an empty string is returned.
-        /// </para>
-        /// </remarks>
-        public ReadOnlySpan<byte> AzpBytes
-        {
-            get
-            {
-                return Payload.GetStringBytesValue(JwtRegisteredClaimNames.Azp);
-            }
-        }
+        #region Header Properties Bytes
 
-        /// <summary>
-        /// Gets the 'value' of the 'jti' claim from the payload.
-        /// </summary>
-        /// <remarks>
-        /// Provides a unique identifier for the JWT.
-        /// see: https://datatracker.ietf.org/doc/html/rfc7519#section-4.1.7
-        /// <para>
-        /// If the 'jti' claim is not found, an empty string is returned.
-        /// </para>
-        /// </remarks>
-        public ReadOnlySpan<byte> IdBytes
-        {
-            get
-            {
-                return Payload.GetStringBytesValue(JwtRegisteredClaimNames.Jti);
-            }
-        }
+        /// <inheritdoc cref="Alg" />
+        public ReadOnlySpan<byte> AlgBytes => Payload.GetStringBytesValue(JwtHeaderParameterNames.Alg);
 
-        /// <summary>
-        /// Gets the 'value' of the 'iss' claim from the payload.
-        /// </summary>
-        /// <remarks>
-        /// Identifies the principal that issued the JWT.
-        /// see: https://datatracker.ietf.org/doc/html/rfc7519#section-4.1.1
-        /// <para>
-        /// If the 'iss' claim is not found, an empty string is returned.
-        /// </para>
-        /// </remarks>
-        public ReadOnlySpan<byte> IssuerBytes
-        {
-            get
-            {
-                return Payload.GetStringBytesValue(JwtRegisteredClaimNames.Iss);
-            }
-        }
+        /// <inheritdoc cref="Cty" />
+        public ReadOnlySpan<byte> CtyBytes => Payload.GetStringBytesValue(JwtHeaderParameterNames.Cty);
+
+        /// <inheritdoc cref="Kid" />
+        public ReadOnlySpan<byte> KidBytes => Payload.GetStringBytesValue(JwtHeaderParameterNames.Kid);
+
+        /// <inheritdoc cref="Typ" />
+        public ReadOnlySpan<byte> TypBytes => Payload.GetStringBytesValue(JwtHeaderParameterNames.Typ);
+
+        /// <inheritdoc cref="X5t" />
+        public ReadOnlySpan<byte> X5tBytes => Payload.GetStringBytesValue(JwtHeaderParameterNames.X5t);
+
+        /// <inheritdoc cref="Zip" />
+        public ReadOnlySpan<byte> ZipBytes => Payload.GetStringBytesValue(JwtHeaderParameterNames.Zip);
 
-#endif
         #endregion
+
+        #region Payload Properties Bytes
+
+        /// <inheritdoc cref="Azp" />
+        public ReadOnlySpan<byte> AzpBytes => Payload.GetStringBytesValue(JwtRegisteredClaimNames.Azp);
+
+        /// <inheritdoc cref="Id" />
+        public ReadOnlySpan<byte> IdBytes => Payload.GetStringBytesValue(JwtRegisteredClaimNames.Jti);
+
+        /// <inheritdoc cref="Issuer" />
+        public ReadOnlySpan<byte> IssuerBytes => Payload.GetStringBytesValue(JwtRegisteredClaimNames.Iss);
+
+        #endregion
+
+#endif
     }
 }
diff --git a/test/Microsoft.IdentityModel.JsonWebTokens.Tests/JsonWebTokenTests.cs b/test/Microsoft.IdentityModel.JsonWebTokens.Tests/JsonWebTokenTests.cs
index a8e1ba983e..d3f6dd5801 100644
--- a/test/Microsoft.IdentityModel.JsonWebTokens.Tests/JsonWebTokenTests.cs
+++ b/test/Microsoft.IdentityModel.JsonWebTokens.Tests/JsonWebTokenTests.cs
@@ -1540,7 +1540,7 @@ public void ParseToken_WithByteProperties()
                     { JwtRegisteredClaimNames.Aud, Default.Audience },
                     { JwtRegisteredClaimNames.Azp, escapedAzp },
                     { JwtRegisteredClaimNames.Jti, Default.Jti },
-                    { "uknown_claim", "unknown_claim_value" },
+                    { "unknown_claim", "unknown_claim_value" },
                 }
             };