diff --git a/ref/Castle.Core-net35.cs b/ref/Castle.Core-net35.cs
index 47b86789be..3b71a55400 100644
--- a/ref/Castle.Core-net35.cs
+++ b/ref/Castle.Core-net35.cs
@@ -3267,6 +3267,7 @@ public void DefineCustomAttributeFor<TAttribute>(Castle.DynamicProxy.Generators.
         public System.Collections.Generic.IEnumerable<Castle.DynamicProxy.Generators.Emitters.SimpleAST.FieldReference> GetAllFields() { }
         public Castle.DynamicProxy.Generators.Emitters.SimpleAST.FieldReference GetField(string name) { }
         public System.Type GetGenericArgument(string genericArgumentName) { }
+        [System.ObsoleteAttribute("Intended for internal use only.")]
         public System.Type[] GetGenericArgumentsFor(System.Type genericType) { }
         public System.Type[] GetGenericArgumentsFor(System.Reflection.MethodInfo genericMethod) { }
         public void SetGenericTypeParameters(System.Reflection.Emit.GenericTypeParameterBuilder[] genericTypeParameterBuilders) { }
diff --git a/ref/Castle.Core-net40.cs b/ref/Castle.Core-net40.cs
index 5a26f531a1..46f77fb0cf 100644
--- a/ref/Castle.Core-net40.cs
+++ b/ref/Castle.Core-net40.cs
@@ -3316,6 +3316,7 @@ public void DefineCustomAttributeFor<TAttribute>(Castle.DynamicProxy.Generators.
         public System.Collections.Generic.IEnumerable<Castle.DynamicProxy.Generators.Emitters.SimpleAST.FieldReference> GetAllFields() { }
         public Castle.DynamicProxy.Generators.Emitters.SimpleAST.FieldReference GetField(string name) { }
         public System.Type GetGenericArgument(string genericArgumentName) { }
+        [System.ObsoleteAttribute("Intended for internal use only.")]
         public System.Type[] GetGenericArgumentsFor(System.Type genericType) { }
         public System.Type[] GetGenericArgumentsFor(System.Reflection.MethodInfo genericMethod) { }
         public void SetGenericTypeParameters(System.Reflection.Emit.GenericTypeParameterBuilder[] genericTypeParameterBuilders) { }
diff --git a/ref/Castle.Core-net45.cs b/ref/Castle.Core-net45.cs
index dc73da89d4..507d407db3 100644
--- a/ref/Castle.Core-net45.cs
+++ b/ref/Castle.Core-net45.cs
@@ -3316,6 +3316,7 @@ public void DefineCustomAttributeFor<TAttribute>(Castle.DynamicProxy.Generators.
         public System.Collections.Generic.IEnumerable<Castle.DynamicProxy.Generators.Emitters.SimpleAST.FieldReference> GetAllFields() { }
         public Castle.DynamicProxy.Generators.Emitters.SimpleAST.FieldReference GetField(string name) { }
         public System.Type GetGenericArgument(string genericArgumentName) { }
+        [System.ObsoleteAttribute("Intended for internal use only.")]
         public System.Type[] GetGenericArgumentsFor(System.Type genericType) { }
         public System.Type[] GetGenericArgumentsFor(System.Reflection.MethodInfo genericMethod) { }
         public void SetGenericTypeParameters(System.Reflection.Emit.GenericTypeParameterBuilder[] genericTypeParameterBuilders) { }
diff --git a/ref/Castle.Core-netstandard1.3.cs b/ref/Castle.Core-netstandard1.3.cs
index 6d0ebef696..acb301c0b7 100644
--- a/ref/Castle.Core-netstandard1.3.cs
+++ b/ref/Castle.Core-netstandard1.3.cs
@@ -2145,6 +2145,7 @@ public void DefineCustomAttributeFor<TAttribute>(Castle.DynamicProxy.Generators.
         public System.Collections.Generic.IEnumerable<Castle.DynamicProxy.Generators.Emitters.SimpleAST.FieldReference> GetAllFields() { }
         public Castle.DynamicProxy.Generators.Emitters.SimpleAST.FieldReference GetField(string name) { }
         public System.Type GetGenericArgument(string genericArgumentName) { }
+        [System.ObsoleteAttribute("Intended for internal use only.")]
         public System.Type[] GetGenericArgumentsFor(System.Type genericType) { }
         public System.Type[] GetGenericArgumentsFor(System.Reflection.MethodInfo genericMethod) { }
         public void SetGenericTypeParameters(System.Reflection.Emit.GenericTypeParameterBuilder[] genericTypeParameterBuilders) { }
diff --git a/ref/Castle.Core-netstandard1.5.cs b/ref/Castle.Core-netstandard1.5.cs
index 22c7ae5592..860763751b 100644
--- a/ref/Castle.Core-netstandard1.5.cs
+++ b/ref/Castle.Core-netstandard1.5.cs
@@ -2145,6 +2145,7 @@ public void DefineCustomAttributeFor<TAttribute>(Castle.DynamicProxy.Generators.
         public System.Collections.Generic.IEnumerable<Castle.DynamicProxy.Generators.Emitters.SimpleAST.FieldReference> GetAllFields() { }
         public Castle.DynamicProxy.Generators.Emitters.SimpleAST.FieldReference GetField(string name) { }
         public System.Type GetGenericArgument(string genericArgumentName) { }
+        [System.ObsoleteAttribute("Intended for internal use only.")]
         public System.Type[] GetGenericArgumentsFor(System.Type genericType) { }
         public System.Type[] GetGenericArgumentsFor(System.Reflection.MethodInfo genericMethod) { }
         public void SetGenericTypeParameters(System.Reflection.Emit.GenericTypeParameterBuilder[] genericTypeParameterBuilders) { }