diff --git a/Command/GenerateGridSourceCommand.php b/Command/GenerateGridSourceCommand.php
index df669a6..b8af87d 100755
--- a/Command/GenerateGridSourceCommand.php
+++ b/Command/GenerateGridSourceCommand.php
@@ -9,7 +9,6 @@
 use Symfony\Component\Console\Input\InputInterface;
 use Symfony\Component\Console\Input\InputOption;
 use Symfony\Component\Console\Output\OutputInterface;
-use Sensio\Bundle\GeneratorBundle\Command\Validators;
 
 /**
  * @deprecated
@@ -33,7 +32,11 @@ protected function configure()
 
     protected function execute(InputInterface $input, OutputInterface $output)
     {
-        $entity = Validators::validateEntityName($input->getArgument('entity_or_document'));
+        // Taken from SensioGeneratorBundle: class Command\Validators (see LICENSE)
+        if (!preg_match('{^[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*:[a-zA-Z0-9_\x7f-\xff\\\/]+$}', $entity = $input->getArgument('entity_or_document'))) {
+            throw new \InvalidArgumentException(sprintf('The entity name isn\'t valid ("%s" given, expecting something like AcmeBlogBundle:Blog/Post)', $entity));
+        }
+
         list($bundle, $entity) = $this->parseShortcutNotation($entity);
 
         $entityClass = $this->getContainer()->get('doctrine')->getAliasNamespace($bundle).'\\'.$entity;
diff --git a/LICENSE b/LICENSE
index 63d1d95..3cee9f1 100644
--- a/LICENSE
+++ b/LICENSE
@@ -1,6 +1,6 @@
 Copyright (c) 2016-2017 Matthew J. Mucklo
 Copyright (c) 2012-2015 David Tee
-Copyright (c) 2004-2013 Fabien Potencier (for code taken from symfony/symfony)
+Copyright (c) 2004-2017 Fabien Potencier (for code taken from symfony/symfony and sensio/generator-bundle)
 
 Permission is hereby granted, free of charge, to any person obtaining a copy of
 this software and associated documentation files (the "Software"), to deal in
diff --git a/composer.json b/composer.json
index 01ed5b2..9d39ee9 100755
--- a/composer.json
+++ b/composer.json
@@ -15,7 +15,6 @@
     ],
     "require": {
         "php": ">=5.6.0",
-        "sensio/generator-bundle": "2.*|3.*|4.*",
         "symfony/framework-bundle": "2.*|3.*|4.*",
         "sensio/framework-extra-bundle": "2.*|3.*|4.*|5.*"
     },