diff --git a/release-tool b/release-tool
index a33af349e..9d9d4fa9f 100755
--- a/release-tool
+++ b/release-tool
@@ -346,7 +346,7 @@ checkSigntoolCommandExists() {
 }
 
 checkCodesignCommandExists() {
-    if !cmdExists codesign; then
+    if ! cmdExists codesign; then
         exitError "codesign command not found on the PATH! Please check that you have correctly installed Xcode."
     fi
 }