diff --git a/src/System.Runtime/ref/System.Runtime.cs b/src/System.Runtime/ref/System.Runtime.cs
index fb0d3690b7a6..c6f5d00ef837 100644
--- a/src/System.Runtime/ref/System.Runtime.cs
+++ b/src/System.Runtime/ref/System.Runtime.cs
@@ -6820,9 +6820,19 @@ public SecurityException(string message, System.Type type, string state) { }
         public object PermitOnlySetInstance { get { throw null; } set { } }
         public string RefusedSet { get { throw null; } set { } }
         public string Url { get { throw null; } set { } }
+        public SecurityZone Zone { get { throw null; } set { } }
         public override void GetObjectData(System.Runtime.Serialization.SerializationInfo info, System.Runtime.Serialization.StreamingContext context) { }
         public override string ToString() { throw null; }
     }
+    public enum SecurityZone
+    {
+        MyComputer = 0,
+        Intranet = 1,
+        Trusted = 2,
+        Internet = 3,
+        Untrusted = 4,
+        NoZone = -1
+    }
     [System.AttributeUsageAttribute((System.AttributeTargets)(1), AllowMultiple=false)]
     public sealed partial class SecurityRulesAttribute : System.Attribute
     {
diff --git a/src/shims/ApiCompatBaseline.netcoreapp.netfx461.txt b/src/shims/ApiCompatBaseline.netcoreapp.netfx461.txt
index f39804c9b9db..c1e1f6927e0c 100644
--- a/src/shims/ApiCompatBaseline.netcoreapp.netfx461.txt
+++ b/src/shims/ApiCompatBaseline.netcoreapp.netfx461.txt
@@ -6,7 +6,6 @@ ApiCompat Error: 0 : Unable to resolve assembly 'Assembly(Name=System.Web.Applic
 ApiCompat Error: 0 : Unable to resolve assembly 'Assembly(Name=System.Configuration, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a)' referenced by the contract assembly 'Assembly(Name=System.Web, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a)'.
 ApiCompat Error: 0 : Unable to resolve assembly 'Assembly(Name=System.ServiceModel, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089)' referenced by the contract assembly 'Assembly(Name=System.Xml.Serialization, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089)'.
 Compat issues with assembly mscorlib:
-MembersMustExist : Member 'System.Security.SecurityException.Zone.set(System.Security.SecurityZone)' does not exist in the implementation but it does exist in the contract.
 MembersMustExist : Member 'System.Security.Cryptography.CspParameters.CryptoKeySecurity.set(System.Security.AccessControl.CryptoKeySecurity)' does not exist in the implementation but it does exist in the contract.
 MembersMustExist : Member 'System.Security.Principal.IdentityReferenceCollection.IsReadOnly.get()' does not exist in the implementation but it does exist in the contract.
 MembersMustExist : Member 'System.Security.Principal.WindowsIdentity..ctor(System.IntPtr, System.String, System.Security.Principal.WindowsAccountType)' does not exist in the implementation but it does exist in the contract.
@@ -95,4 +94,4 @@ MembersMustExist : Member 'System.Data.SqlClient.SqlParameterCollection.Add(Syst
 Compat issues with assembly System.Xml:
 MembersMustExist : Member 'System.Xml.Xsl.XslCompiledTransform.TemporaryFiles.get()' does not exist in the implementation but it does exist in the contract.
 MembersMustExist : Member 'System.Xml.Xsl.XslTransform.Load(System.Xml.XPath.XPathNavigator, System.Xml.XmlResolver, System.Security.Policy.Evidence)' does not exist in the implementation but it does exist in the contract.
-Total Issues: 85
+Total Issues: 84
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