diff --git a/CloudinaryDotNet.Tests/Asset/UrlBuilderTest.cs b/CloudinaryDotNet.Tests/Asset/UrlBuilderTest.cs
index f16b9df9..b884e648 100644
--- a/CloudinaryDotNet.Tests/Asset/UrlBuilderTest.cs
+++ b/CloudinaryDotNet.Tests/Asset/UrlBuilderTest.cs
@@ -1,7 +1,7 @@
 using System;
 using System.Collections.Generic;
 using System.Net.Http;
-using System.Linq;
+using System.Net.Http.Headers;
 using System.Text.RegularExpressions;
 using CloudinaryDotNet.Actions;
 using NUnit.Framework;
@@ -475,23 +475,51 @@ public void TestExcludeEmptyTransformation()
             Assert.AreEqual(TestConstants.DefaultImageUpPath + "c_fill,x_100,y_100/test", uri);
         }
 
-        [Test]
-        public void TestAgentPlatformHeaders()
+        private HttpRequestMessage CreateRequest(string userPlatformProduct, string userPlatformVersion = null)
         {
             var request = new HttpRequestMessage { RequestUri = new Uri("http://dummy.com") };
-            m_api.UserPlatform = "Test/1.0";
+            m_api.UserPlatform = new ProductHeaderValue(userPlatformProduct, userPlatformVersion);
 
             m_api.PrepareRequestBody(
                 request,
                 HttpMethod.GET,
                 new SortedDictionary<string, object>(),
                 new FileDescription(""));
+            return request;
+        }
+
+        [Test]
+        public void TestAgentPlatformHeaders()
+        {
+            var httpRequestMessage = CreateRequest("UserPlatform", "2.3");
 
             //Can't test the result, so we just verify the UserAgent parameter is sent to the server
-            StringAssert.AreEqualIgnoringCase($"{m_api.UserPlatform} {ApiShared.USER_AGENT}",
-                request.Headers.UserAgent.ToString());
-            StringAssert.IsMatch(@"Test\/1\.0 CloudinaryDotNet\/(\d+)\.(\d+)\.(\d+) \(.*\)",
-                request.Headers.UserAgent.ToString());
+            StringAssert.IsMatch(@"CloudinaryDotNet\/(\d+)\.(\d+)\.(\d+) \(.*\) UserPlatform/2\.3",
+                httpRequestMessage.Headers.UserAgent.ToString());
+        }
+
+        [Test]
+        [TestCase("Mono 5.11.0 ((HEAD/768f1b247c6)")]
+        public void TestMalformedFrameworkVersion(string dotnetVersion)
+        {
+            var previousFramework = m_api.DotnetVersion;
+            try
+            {
+                m_api.DotnetVersion = dotnetVersion;
+                Assert.DoesNotThrow(() => CreateRequest("p"));
+            }
+            finally
+            {
+                m_api.DotnetVersion = previousFramework;
+            }
+        }
+        
+        [Test]
+        [TestCase("UserPlatform", null)]
+        [TestCase("UserPlatform", "1.2")]
+        public void TestUserPlatformCombinations(string userPlatformProduct, string userPlatformVersion)
+        {
+            Assert.DoesNotThrow(() => CreateRequest(userPlatformProduct, userPlatformVersion));
         }
 
         [Test]
diff --git a/CloudinaryDotNet/ApiShared.Internal.cs b/CloudinaryDotNet/ApiShared.Internal.cs
index cdb5860f..1b8186f3 100644
--- a/CloudinaryDotNet/ApiShared.Internal.cs
+++ b/CloudinaryDotNet/ApiShared.Internal.cs
@@ -455,12 +455,16 @@ private void PrePrepareRequestBody(
 
             // Add platform information to the USER_AGENT header
             // This is intended for platform information and not individual applications!
-            var userPlatform = string.IsNullOrEmpty(UserPlatform)
-                ? USER_AGENT
-                : string.Format(CultureInfo.InvariantCulture, "{0} {1}", UserPlatform, USER_AGENT);
-            request.Headers.Add("User-Agent", userPlatform);
+            var userAgentHeader = request.Headers.UserAgent;
+            userAgentHeader.Add(new ProductInfoHeaderValue("CloudinaryDotNet", CloudinaryVersion.Full));
+            userAgentHeader.Add(new ProductInfoHeaderValue($"({DotnetVersion})"));
 
-            byte[] authBytes = Encoding.ASCII.GetBytes(GetApiCredentials());
+            if (UserPlatform != null)
+            {
+                userAgentHeader.Add(new ProductInfoHeaderValue(UserPlatform));
+            }
+
+            var authBytes = Encoding.ASCII.GetBytes(GetApiCredentials());
             request.Headers.Add("Authorization", string.Format(CultureInfo.InvariantCulture, "Basic {0}", Convert.ToBase64String(authBytes)));
 
             if (extraHeaders != null)
diff --git a/CloudinaryDotNet/ApiShared.cs b/CloudinaryDotNet/ApiShared.cs
index f4fdc6ba..b7b1ecbd 100644
--- a/CloudinaryDotNet/ApiShared.cs
+++ b/CloudinaryDotNet/ApiShared.cs
@@ -6,10 +6,12 @@
     using System.Globalization;
     using System.Linq;
     using System.Net.Http;
+    using System.Net.Http.Headers;
     using System.Reflection;
     using System.Runtime.InteropServices;
     using System.Runtime.Serialization;
     using System.Text;
+    using System.Text.RegularExpressions;
     using System.Threading;
     using System.Threading.Tasks;
     using CloudinaryDotNet.Actions;
@@ -68,11 +70,6 @@ public partial class ApiShared : ISignProvider
         /// </summary>
         public const string HTTP_BOUNDARY = "notrandomsequencetouseasboundary";
 
-        /// <summary>
-        /// User agent for cloudinary API requests.
-        /// </summary>
-        public static string USER_AGENT = BuildUserAgent();
-
         /// <summary>
         /// Whether to use a sub domain.
         /// </summary>
@@ -111,7 +108,7 @@ public partial class ApiShared : ISignProvider
         /// <summary>
         /// User platform information.
         /// </summary>
-        public string UserPlatform;
+        public ProductHeaderValue UserPlatform;
 
         /// <summary>
         /// Timeout for the API requests, milliseconds.
@@ -150,6 +147,8 @@ public partial class ApiShared : ISignProvider
         private readonly Func<string, HttpRequestMessage> requestBuilder =
             (url) => new HttpRequestMessage { RequestUri = new Uri(url) };
 
+        private string dotnetVersion;
+
         /// <summary>
         /// Initializes a new instance of the <see cref="ApiShared"/> class.
         /// Default parameterless constructor.
@@ -382,6 +381,24 @@ public Url ApiUrlVideoUpV
             }
         }
 
+        /// <summary>
+        /// Gets or sets the .NET version compatible with Http headers comment specification.
+        /// </summary>
+        internal string DotnetVersion
+        {
+            get
+            {
+                if (dotnetVersion == null)
+                {
+                    DotnetVersion = System.Runtime.InteropServices.RuntimeInformation.FrameworkDescription;
+                }
+
+                return dotnetVersion;
+            }
+
+            set => dotnetVersion = GetUserAgentCommentFriendlyValue(value);
+        }
+
         /// <summary>
         /// Gets cloudinary parameter from enumeration.
         /// </summary>
@@ -628,12 +645,12 @@ public string SignParameters(IDictionary<string, object> parameters)
             StringBuilder signBase = new StringBuilder(string.Join("&", parameters.
                                                                    Where(pair => pair.Value != null && !excludedSignatureKeys.Any(s => pair.Key.Equals(s, StringComparison.Ordinal)))
                 .Select(pair =>
-                       {
-                           var value = pair.Value is IEnumerable<string>
-                               ? string.Join(",", ((IEnumerable<string>)pair.Value).ToArray())
-                               : pair.Value.ToString();
-                           return string.Format(CultureInfo.InvariantCulture, "{0}={1}", pair.Key, value);
-                       })
+                {
+                    var value = pair.Value is IEnumerable<string>
+                        ? string.Join(",", ((IEnumerable<string>)pair.Value).ToArray())
+                        : pair.Value.ToString();
+                    return string.Format(CultureInfo.InvariantCulture, "{0}={1}", pair.Key, value);
+                })
                 .ToArray()));
 
             signBase.Append(Account.ApiSecret);
@@ -799,9 +816,10 @@ public string BuildUploadFormShared(string field, string resourceType, SortedDic
             return builder.ToString();
         }
 
-        private static string BuildUserAgent()
-        {
-            return $"CloudinaryDotNet/{CloudinaryVersion.Full} ({RuntimeInformation.FrameworkDescription})";
-        }
+        // Nonmatching braces are not accepted, so we just remove them all.
+        // See https://github.com/aspnet/HttpAbstractions/blob/master/src/Microsoft.Net.Http.Headers/HttpRuleParser.cs#L250
+        // for details.
+        private static string GetUserAgentCommentFriendlyValue(string value)
+            => Regex.Replace(value, "\\(|\\)", string.Empty);
     }
 }