diff --git a/eng/Build.ps1 b/eng/Build.ps1
index 26d30e99c37..f189acc036c 100644
--- a/eng/Build.ps1
+++ b/eng/Build.ps1
@@ -214,11 +214,11 @@ function Process-Arguments() {
 
     if ($buildnorealsig) {
         $script:buildnorealsig = $True;
-        $env:FSHARP_REALSIG="false"
+        $env:FSHARP_REALSIG="true"
     }
     else {
         $script:buildnorealsig = $False;
-        $env:FSHARP_REALSIG="true"
+        $env:FSHARP_REALSIG="false"
     }        
     if ($verifypackageshipstatus) {
         $script:verifypackageshipstatus = $True;