diff --git a/src/main/java/ru/dbotthepony/mc/otm/matter/MatterRegistry.java b/src/main/java/ru/dbotthepony/mc/otm/matter/MatterRegistry.java
index 7d66f911e..2506cbea8 100644
--- a/src/main/java/ru/dbotthepony/mc/otm/matter/MatterRegistry.java
+++ b/src/main/java/ru/dbotthepony/mc/otm/matter/MatterRegistry.java
@@ -452,8 +452,15 @@ public class MatterRegistry {
 		}
 	}
 
+	private static boolean started_once = false;
+
 	@SubscribeEvent
 	public static void serverStarted(FMLServerStartedEvent event) {
+		if (started_once)
+			return;
+
+		started_once = true;
+
 		ITEMS.clear();
 		usages.clear();
 		results.clear();