diff --git a/src/libraries/System.Private.Xml/tests/XmlSchema/XmlSchemaSet/TC_SchemaSet_Compile.cs b/src/libraries/System.Private.Xml/tests/XmlSchema/XmlSchemaSet/TC_SchemaSet_Compile.cs
index b360f5bd19ecef..43fde8b0faaaed 100644
--- a/src/libraries/System.Private.Xml/tests/XmlSchema/XmlSchemaSet/TC_SchemaSet_Compile.cs
+++ b/src/libraries/System.Private.Xml/tests/XmlSchema/XmlSchemaSet/TC_SchemaSet_Compile.cs
@@ -85,6 +85,7 @@ public void v2()
             Assert.True(false);
         }
 
+        [ActiveIssue(27740, TestPlatforms.AnyUnix)]
         [Fact]
         //[Variation(Desc = "TFS_470021 Unexpected local particle qualified name when chameleon schema is added to set")]
         public void TFS_470021()
diff --git a/src/libraries/System.Private.Xml/tests/XmlSchema/XmlSchemaValidatorApi/ValidateMisc.cs b/src/libraries/System.Private.Xml/tests/XmlSchema/XmlSchemaValidatorApi/ValidateMisc.cs
index 31e44a8e33e66f..707709f43cde24 100644
--- a/src/libraries/System.Private.Xml/tests/XmlSchema/XmlSchemaValidatorApi/ValidateMisc.cs
+++ b/src/libraries/System.Private.Xml/tests/XmlSchema/XmlSchemaValidatorApi/ValidateMisc.cs
@@ -893,6 +893,7 @@ public void CreateSchema2(string testDirectory)
         }
 
         //TFS_538324
+        [ActiveIssue(27740, TestPlatforms.AnyUnix)]
         [Fact]
         public void XSDValidationGeneratesInvalidError_1()
         {
@@ -919,6 +920,7 @@ public void XSDValidationGeneratesInvalidError_1()
         }
 
         //TFS_538324
+        [ActiveIssue(27740, TestPlatforms.AnyUnix)]
         [Fact]
         public void XSDValidationGeneratesInvalidError_2()
         {