diff --git a/src/linker/Linker.Steps/MarkStep.cs b/src/linker/Linker.Steps/MarkStep.cs
index 4d45c2737c18..e0fdfb266075 100644
--- a/src/linker/Linker.Steps/MarkStep.cs
+++ b/src/linker/Linker.Steps/MarkStep.cs
@@ -679,7 +679,7 @@ protected void MarkCustomAttributeProperty (CustomAttributeNamedArgument namedAr
 			if (property != null)
 				MarkMethod (property.SetMethod);
 
-			MarkIfType (namedArgument.Argument);
+			MarkCustomAttributeArgument (namedArgument.Argument);
 			Tracer.Pop ();
 		}
 
@@ -711,7 +711,7 @@ protected void MarkCustomAttributeField (CustomAttributeNamedArgument namedArgum
 			if (field != null)
 				MarkField (field);
 
-			MarkIfType (namedArgument.Argument);
+			MarkCustomAttributeArgument (namedArgument.Argument);
 		}
 
 		FieldDefinition GetField (TypeDefinition type, string fieldname)
@@ -746,26 +746,39 @@ void MarkCustomAttributeArguments (CustomAttribute ca)
 				return;
 
 			foreach (var argument in ca.ConstructorArguments)
-				MarkIfType (argument);
+				MarkCustomAttributeArgument (argument);
 		}
 
-		void MarkIfType (CustomAttributeArgument argument)
+		void MarkCustomAttributeArgument (CustomAttributeArgument argument)
 		{
 			var at = argument.Type;
+
 			if (at.IsArray) {
 				var et = at.GetElementType ();
-				if (et.Namespace != "System" || et.Name != "Type")
-					return;
 
 				MarkType (et);
 				if (argument.Value == null)
 					return;
 
-				foreach (var cac in (CustomAttributeArgument[]) argument.Value)
-					MarkWithResolvedScope ((TypeReference) cac.Value);
-			} else if (at.Namespace == "System" && at.Name == "Type") {
-				MarkType (argument.Type);
-				MarkWithResolvedScope ((TypeReference) argument.Value);
+				foreach (var caa in (CustomAttributeArgument [])argument.Value)
+					MarkCustomAttributeArgument (caa);
+
+				return;
+			}
+
+			if (at.Namespace == "System") {
+				switch (at.Name) {
+				case "Type":
+					MarkType (argument.Type);
+					MarkWithResolvedScope ((TypeReference)argument.Value);
+					return;
+
+				case "Object":
+					var boxed_value = (CustomAttributeArgument)argument.Value;
+					MarkType (boxed_value.Type);
+					MarkCustomAttributeArgument (boxed_value);
+					return;
+				}
 			}
 		}
 
diff --git a/test/Mono.Linker.Tests.Cases/Attributes/BoxedValues.cs b/test/Mono.Linker.Tests.Cases/Attributes/BoxedValues.cs
new file mode 100644
index 000000000000..0d4448ccba2c
--- /dev/null
+++ b/test/Mono.Linker.Tests.Cases/Attributes/BoxedValues.cs
@@ -0,0 +1,105 @@
+using System;
+using Mono.Linker.Tests.Cases.Expectations.Assertions;
+
+namespace Mono.Linker.Tests.Cases.Attributes {
+	public class BoxedValues {
+		// mcs bug
+		//        [TestAttribute ((object)typeof (Enum_2))]
+		//		[Kept]
+		//		[KeptAttributeAttribute (typeof (TestAttribute))]
+		//		public void Test_1 ()
+		//        {
+		//        }
+
+		[TestAttribute (TestProperty = Enum_2.B)]
+		[Kept]
+		[KeptAttributeAttribute (typeof (TestAttribute))]
+		public void Test_2 ()
+		{
+		}
+
+		[TestAttribute (TestField = Enum_3.C)]
+		[Kept]
+		[KeptAttributeAttribute (typeof (TestAttribute))]
+		public void Test_3 ()
+		{
+		}
+
+		[TestAttribute (TestProperty = new object [] { Enum_4.B, null, typeof (Enum_5) })]
+		[Kept]
+		[KeptAttributeAttribute (typeof (TestAttribute))]
+		public void Test_4 ()
+		{
+		}
+
+		static void Main ()
+		{
+			typeof (BoxedValues).GetMethod ("Test_1").GetCustomAttributes (false);
+			typeof (BoxedValues).GetMethod ("Test_2").GetCustomAttributes (false);
+			typeof (BoxedValues).GetMethod ("Test_3").GetCustomAttributes (false);
+			typeof (BoxedValues).GetMethod ("Test_4").GetCustomAttributes (false);
+		}
+	}
+
+	[KeptBaseType (typeof (System.Attribute))]
+	public class TestAttribute : Attribute {
+		[Kept]
+		public TestAttribute ()
+		{
+		}
+
+		//[Kept]
+		public TestAttribute (object arg)
+		{
+		}
+
+		[KeptBackingField]
+		[Kept]
+		public object TestProperty { get; [Kept] set; }
+
+		[Kept]
+		public object TestField;
+	}
+
+	public enum Enum_1 {
+		A = 1,
+		B,
+		C
+	}
+
+	[Kept]
+	[KeptMember ("value__")]
+	[KeptBaseType (typeof (Enum))]
+	public enum Enum_2 {
+		[Kept]
+		A = 1,
+		[Kept]
+		B,
+		[Kept]
+		C
+	}
+
+	[Kept]
+	[KeptMember ("value__")]
+	[KeptBaseType (typeof (Enum))]
+	public enum Enum_3 {
+		[Kept]
+		C
+	}
+
+	[Kept]
+	[KeptMember ("value__")]
+	[KeptBaseType (typeof (Enum))]
+	public enum Enum_4 {
+		[Kept]
+		B
+	}
+
+	[Kept]
+	[KeptMember ("value__")]
+	[KeptBaseType (typeof (Enum))]
+	public enum Enum_5 {
+		[Kept]
+		B
+	}
+}
\ No newline at end of file