diff --git a/typo3/sysext/t3skin/composer.json b/typo3/sysext/t3skin/composer.json
index f1a32fa052d603d255311bbeccb00070f76042ca..9b55473fc3fc1e042c56583e38ceb578dca51fe7 100644
--- a/typo3/sysext/t3skin/composer.json
+++ b/typo3/sysext/t3skin/composer.json
@@ -15,6 +15,7 @@
 	"extra": {
 		"typo3/cms": {
 			"Package": {
+				"protected": true,
 				"partOfFactoryDefault": true,
 				"partOfMinimalUsableSystem": true
 			}