diff --git a/composer.json b/composer.json
index 4915fdf..bd1bbc7 100644
--- a/composer.json
+++ b/composer.json
@@ -24,7 +24,7 @@
 	"prefer-dist": true,
 	"require": {
 		"php": ">=5.6",
-		"symfony/validator": "^2.7",
+		"symfony/validator": "^2.7|^3.3|^4.0",
 		"psr/simple-cache": "^1.0"
 	},
 	"autoload": {