diff --git a/edd-software-license-manager.php b/edd-software-license-manager.php
index b72ce33..8cc5f59 100644
--- a/edd-software-license-manager.php
+++ b/edd-software-license-manager.php
@@ -26,6 +26,10 @@
     exit;
 }
 
+if( !class_exists( 'Easy Digital Downloads' ) ) {
+    return;
+}
+
 if( !class_exists( 'EDD_SLM' ) ) {
 
     /**
@@ -171,4 +175,4 @@ function EDD_SLM_load() {
 
     add_action( 'plugins_loaded', 'EDD_SLM_load' );
 
-} // End if class_exists check
\ No newline at end of file
+} // End if class_exists check