diff --git a/src/Composer/Command/LicensesCommand.php b/src/Composer/Command/LicensesCommand.php
index 748b5b85d..52d0d0122 100644
--- a/src/Composer/Command/LicensesCommand.php
+++ b/src/Composer/Command/LicensesCommand.php
@@ -12,6 +12,7 @@
 
 namespace Composer\Command;
 
+use Composer\Console\Input\InputOption;
 use Composer\Json\JsonFile;
 use Composer\Package\CompletePackageInterface;
 use Composer\Plugin\CommandEvent;
@@ -22,7 +23,6 @@ use Composer\Util\PackageInfo;
 use Symfony\Component\Console\Formatter\OutputFormatter;
 use Symfony\Component\Console\Helper\Table;
 use Symfony\Component\Console\Input\InputInterface;
-use Symfony\Component\Console\Input\InputOption;
 use Symfony\Component\Console\Output\OutputInterface;
 use Symfony\Component\Console\Style\SymfonyStyle;
 
@@ -40,7 +40,7 @@ class LicensesCommand extends BaseCommand
             ->setName('licenses')
             ->setDescription('Shows information about licenses of dependencies.')
             ->setDefinition(array(
-                new InputOption('format', 'f', InputOption::VALUE_REQUIRED, 'Format of the output: text, json or summary', 'text'),
+                new InputOption('format', 'f', InputOption::VALUE_REQUIRED, 'Format of the output: text, json or summary', 'text', ['text', 'json', 'summary']),
                 new InputOption('no-dev', null, InputOption::VALUE_NONE, 'Disables search in require-dev packages.'),
             ))
             ->setHelp(
diff --git a/src/Composer/Command/OutdatedCommand.php b/src/Composer/Command/OutdatedCommand.php
index 8a8b8b0e6..ffa9ba3af 100644
--- a/src/Composer/Command/OutdatedCommand.php
+++ b/src/Composer/Command/OutdatedCommand.php
@@ -42,7 +42,7 @@ class OutdatedCommand extends BaseCommand
                 new InputOption('strict', null, InputOption::VALUE_NONE, 'Return a non-zero exit code when there are outdated packages'),
                 new InputOption('minor-only', 'm', InputOption::VALUE_NONE, 'Show only packages that have minor SemVer-compatible updates. Use with the --outdated option.'),
                 new InputOption('patch-only', 'p', InputOption::VALUE_NONE, 'Show only packages that have patch SemVer-compatible updates. Use with the --outdated option.'),
-                new InputOption('format', 'f', InputOption::VALUE_REQUIRED, 'Format of the output: text or json', 'text'),
+                new InputOption('format', 'f', InputOption::VALUE_REQUIRED, 'Format of the output: text or json', 'text', ['json', 'text']),
                 new InputOption('ignore', null, InputOption::VALUE_REQUIRED | InputOption::VALUE_IS_ARRAY, 'Ignore specified package(s). Use it with the --outdated option if you don\'t want to be informed about new versions of some packages.', null, $this->suggestInstalledPackage()),
                 new InputOption('no-dev', null, InputOption::VALUE_NONE, 'Disables search in require-dev packages.'),
                 new InputOption('ignore-platform-req', null, InputOption::VALUE_REQUIRED | InputOption::VALUE_IS_ARRAY, 'Ignore a specific platform requirement (php & ext- packages). Use with the --outdated option'),
diff --git a/tests/Composer/Test/CompletionFunctionalTest.php b/tests/Composer/Test/CompletionFunctionalTest.php
index 36aa3fe8d..32baa33ce 100644
--- a/tests/Composer/Test/CompletionFunctionalTest.php
+++ b/tests/Composer/Test/CompletionFunctionalTest.php
@@ -50,7 +50,7 @@ class CompletionFunctionalTest extends TestCase
         yield ['init --require-dev foo/bar --require-dev ', [$randomVendor]];
 
         yield ['install --prefer-install ', $preferInstall];
-        yield ['install ', $installedPackages];
+        yield ['install ', null];
 
         yield ['outdated ', $installedPackages];