diff --git a/src/Composer/Package/Loader/RootPackageLoader.php b/src/Composer/Package/Loader/RootPackageLoader.php
index 76ae63488..f0c25daba 100644
--- a/src/Composer/Package/Loader/RootPackageLoader.php
+++ b/src/Composer/Package/Loader/RootPackageLoader.php
@@ -201,16 +201,18 @@ class RootPackageLoader extends ArrayLoader
                 continue;
             }
 
-            // infer flags for requirements that have an explicit -dev or -beta version specified but only
-            // for those that are more unstable than the minimumStability or existing flags
-            $reqVersion = preg_replace('{^([^,\s@]+) as .+$}', '$1', $reqVersion);
-            if (preg_match('{^[^,\s@]+$}', $reqVersion) && 'stable' !== ($stabilityName = VersionParser::parseStability($reqVersion))) {
-                $name = strtolower($reqName);
-                $stability = $stabilities[$stabilityName];
-                if ((isset($stabilityFlags[$name]) && $stabilityFlags[$name] > $stability) || ($minimumStability > $stability)) {
-                    continue;
+            foreach ($constraints as $constraint) {
+                // infer flags for requirements that have an explicit -dev or -beta version specified but only
+                // for those that are more unstable than the minimumStability or existing flags
+                $reqVersion = preg_replace('{^([^,\s@]+) as .+$}', '$1', $constraint);
+                if (preg_match('{^[^,\s@]+$}', $reqVersion) && 'stable' !== ($stabilityName = VersionParser::parseStability($reqVersion))) {
+                    $name = strtolower($reqName);
+                    $stability = $stabilities[$stabilityName];
+                    if ((isset($stabilityFlags[$name]) && $stabilityFlags[$name] > $stability) || ($minimumStability > $stability)) {
+                        continue;
+                    }
+                    $stabilityFlags[$name] = $stability;
                 }
-                $stabilityFlags[$name] = $stability;
             }
         }
 
diff --git a/tests/Composer/Test/Package/Loader/RootPackageLoaderTest.php b/tests/Composer/Test/Package/Loader/RootPackageLoaderTest.php
index 0b311041e..951645971 100644
--- a/tests/Composer/Test/Package/Loader/RootPackageLoaderTest.php
+++ b/tests/Composer/Test/Package/Loader/RootPackageLoaderTest.php
@@ -44,6 +44,8 @@ class RootPackageLoaderTest extends \PHPUnit_Framework_TestCase
                 'zux/complex' => '~1.0,>=1.0.2@dev',
                 'or/op' => '^2.0@dev || ^2.0@dev',
                 'multi/lowest-wins' => '^2.0@rc || >=3.0@dev , ~3.5@alpha',
+                'or/op/without-flags' => 'dev-master || 2.0 , ~3.5-alpha',
+                'or/op/without-flags2' => '3.0-beta || 2.0 , ~3.5-alpha',
             ),
             'minimum-stability' => 'alpha',
         ));
@@ -55,6 +57,8 @@ class RootPackageLoaderTest extends \PHPUnit_Framework_TestCase
             'zux/complex' => BasePackage::STABILITY_DEV,
             'or/op' => BasePackage::STABILITY_DEV,
             'multi/lowest-wins' => BasePackage::STABILITY_DEV,
+            'or/op/without-flags' => BasePackage::STABILITY_DEV,
+            'or/op/without-flags2' => BasePackage::STABILITY_ALPHA,
         ), $package->getStabilityFlags());
     }