diff --git a/scripts/verify-sign.ps1 b/scripts/verify-sign.ps1
index a2368926d2..f3c36833ef 100644
--- a/scripts/verify-sign.ps1
+++ b/scripts/verify-sign.ps1
@@ -30,7 +30,7 @@ $env:TP_TOOLS_DIR = Join-Path $env:TP_ROOT_DIR "tools"
 Write-Verbose "Setup build configuration."
 $TPB_SignCertificate = $Certificate
 $TPB_Configuration = $Configuration
-$TPB_AssembliesPattern = @("*test*.dll", "*qualitytools*.dll", "*test*.exe", "*datacollector*.dll", "*datacollector*.exe", "QTAgent*.exe", "VsWebSite.Interop.dll", "Microsoft.VisualStudio*.dll", "Microsoft.TestPlatform.Build.dll", "Microsoft.DiaSymReader.dll", "Microsoft.IntelliTrace*.dll", "concrt140.dll", "msvcp140.dll", "vccorlib140.dll", "vcruntime140.dll", "codecoveragemessages.dll", "covrun32.dll", "msdia140.dll", "covrun64.dll", "IntelliTrace.exe", "ProcessSnapshotCleanup.exe", "TDEnvCleanup.exe", "CodeCoverage.exe", "Microsoft.ShDocVw.dll", "UIAComwrapper.dll", "Interop.UIAutomationClient.dll", "SettingsMigrator.exe")
+$TPB_AssembliesPattern = @("*test*.dll", "*qualitytools*.dll", "*test*.exe", "*datacollector*.dll", "*datacollector*.exe", "QTAgent*.exe", "VsWebSite.Interop.dll", "Microsoft.VisualStudio*.dll", "Microsoft.TestPlatform.Build.dll", "Microsoft.DiaSymReader.dll", "Microsoft.IntelliTrace*.dll", "concrt140.dll", "msvcp140.dll", "vccorlib140.dll", "vcruntime140.dll", "codecoveragemessages.dll", "covrun32.dll", "msdia140.dll", "covrun64.dll", "IntelliTrace.exe", "ProcessSnapshotCleanup.exe", "TDEnvCleanup.exe", "CodeCoverage.exe", "Microsoft.ShDocVw.dll", "UIAComwrapper.dll", "Interop.UIAutomationClient.dll", "SettingsMigrator.exe", "Newtonsoft.Json.dll")
 
 function Verify-Assemblies
 {
@@ -54,18 +54,22 @@ function Verify-Assemblies
                     elseif ($signature.SignerCertificate.Thumbprint -eq "5EAD300DC7E4D637948ECB0ED829A072BD152E17") {
                         Write-Log "Valid (Prod Signed): $($_.FullName)."
                     }
-		    # For some dlls e.g. "Interop.UIAutomationClient.dll", sign certificate is different signature. Skip such binaries.
+		            # For some dlls e.g. "Interop.UIAutomationClient.dll", sign certificate is different signature. Skip such binaries.
                     elseif ($signature.SignerCertificate.Thumbprint -eq "67B1757863E3EFF760EA9EBB02849AF07D3A8080") {
                         Write-Log "Valid (Prod Signed): $($_.FullName)."
                     }
-		    # For some dlls e.g. "Microsoft.VisualStudio.ArchitectureTools.PEReader.dll", sign certificate is different signature. Skip such binaries.
+		            # For some dlls e.g. "Microsoft.VisualStudio.ArchitectureTools.PEReader.dll", sign certificate is different signature. Skip such binaries.
                     elseif ($signature.SignerCertificate.Thumbprint -eq "9DC17888B5CFAD98B3CB35C1994E96227F061675") {
                         Write-Log "Valid (Prod Signed): $($_.FullName)."
                     }
-		    # For some dlls sign certificate is different signature. Skip such binaries.
+		            # For some dlls sign certificate is different signature. Skip such binaries.
                     elseif ($signature.SignerCertificate.Thumbprint -eq "62009AAABDAE749FD47D19150958329BF6FF4B34") {
                         Write-Log "Valid (Prod Signed): $($_.FullName)."
                     }
+                    # Microsoft 3rd Party Authenticode Signature
+                    elseif ($signature.SignerCertificate.Thumbprint -eq "899FA016DEE8E665FF2A315A1151C43FB96C430B") {
+                        Write-Log "Valid (Prod Signed): $($_.FullName)."
+                    }
                     else {
                         Write-FailLog "Incorrect certificate. File: $($_.FullName). Certificate: $($signature.SignerCertificate.Thumbprint)."
                     }
diff --git a/src/package/sign/sign.proj b/src/package/sign/sign.proj
index 03062efeee..24719cc38c 100644
--- a/src/package/sign/sign.proj
+++ b/src/package/sign/sign.proj
@@ -155,6 +155,9 @@
       <AssembliesToSign Include="$(ArtifactsDirectory)CUITPlugins\Microsoft.VisualStudio.TestTools.UITest.Extension.Uia.dll" />
       <AssembliesToSign Include="$(ArtifactsDirectory)CUITPlugins\Microsoft.VisualStudio.TestTools.UITest.Extension.UiaWidget.dll" />
       <AssembliesToSign Include="$(ArtifactsDirectory)CUITPlugins\Microsoft.VisualStudio.TestTools.UITest.Extension.UiaWidget.UIAHtmlElementUtilities.dll" />
+
+      <!-- Third Party assemblies to sign -->
+      <ThirdPartyAssembliesToSign Include="$(ArtifactsDirectory)Newtonsoft.Json.dll" />
     </ItemGroup>
 
     <!-- Sign test platform v2 assemblies for .NET 4.6-->
@@ -200,6 +203,9 @@
       <!-- Localized resources -->
       <AssembliesToSign Include="$(ArtifactsDirectory)%(ResxLang.Identity)\*.*" />
       <AssembliesToSign Include="$(ArtifactsDirectory)Extensions\%(ResxLang.Identity)\*.*" />
+
+      <!-- Third Party assemblies to sign -->
+      <ThirdPartyAssembliesToSign Include="$(ArtifactsDirectory)Newtonsoft.Json.dll" />
     </ItemGroup>
 
     <!-- Intellitrace -->
@@ -308,6 +314,10 @@
       <CoreAssembliesToSign Include="$(ArtifactsCoreDirectory)%(ResxLang.Identity)\*.*" />
       <CoreAssembliesToSign Include="$(ArtifactsCoreDirectory)Extensions\%(ResxLang.Identity)\*.*" />
       <CoreAssembliesToSign Include="$(ArtifactsCoreDirectory)TestHost\%(ResxLang.Identity)\*.*" />
+
+      <!-- Third Party assemblies to sign -->
+      <ThirdPartyAssembliesToSign Include="$(ArtifactsCoreDirectory)Newtonsoft.Json.dll" />
+      <ThirdPartyAssembliesToSign Include="$(ArtifactsCoreDirectory)TestHost\Newtonsoft.Json.dll" />
     </ItemGroup>
 
     <!-- Sign Microsoft.TestPlatform.Build -->
@@ -384,6 +394,11 @@
       <TestHostCoreAssembliesToSign Include="$(ArtifactsBaseDirectory)Microsoft.TestPlatform.TestHost\netcoreapp2.1\%(ResxLang.Identity)\*.*" />
       <TestHostCoreAssembliesToSign Include="$(ArtifactsBaseDirectory)Microsoft.TestPlatform.TestHost\net451\$(TargetRuntime)\%(ResxLang.Identity)\*.*" />
       <TestHostCoreAssembliesToSign Include="$(ArtifactsBaseDirectory)Microsoft.TestPlatform.TestHost\uap10.0\%(ResxLang.Identity)\*.*" />
+      
+      <!-- Third Party assemblies to sign -->
+      <ThirdPartyAssembliesToSign Include="$(ArtifactsBaseDirectory)Microsoft.TestPlatform.TestHost\netcoreapp2.1\Newtonsoft.Json.dll" />
+      <ThirdPartyAssembliesToSign Include="$(ArtifactsBaseDirectory)Microsoft.TestPlatform.TestHost\uap10.0\Newtonsoft.Json.dll" />
+      <ThirdPartyAssembliesToSign Include="$(ArtifactsBaseDirectory)Microsoft.TestPlatform.TestHost\net451\$(TargetRuntime)\Newtonsoft.Json.dll" />
     </ItemGroup>
 
     <ItemGroup>
@@ -416,8 +431,18 @@
         <Authenticode>Microsoft402400</Authenticode>
         <StrongName>StrongName</StrongName>
       </CodeCoverageAssembliesToSign>
+
+      <ThirdPartyAssembliesToSign>
+        <Authenticode>3PartySHA2</Authenticode>
+      </ThirdPartyAssembliesToSign>
     </ItemGroup>
 
+    <Message Text="Signing 3rd party assemblies using authenticode certificate '%(ThirdPartyAssembliesToSign.Authenticode)' for @(CoreAssembliesToSign)"/>
+    <SignFiles Files="@(ThirdPartyAssembliesToSign)"
+               BinariesDirectory="$(ArtifactsBaseDirectory)"
+               IntermediatesDirectory="$(IntermediatesDirectory)"
+               Type="$(SignType)" />
+
     <Message Text="Signing using authenticode certificate '%(AssembliesToSign.Authenticode)' for @(AssembliesToSign)"/>
     <SignFiles Files="@(AssembliesToSign)"
                BinariesDirectory="$(ArtifactsDirectory)"