diff --git a/src/main/java/refinedstorage/apiimpl/storage/GroupedStorage.java b/src/main/java/refinedstorage/apiimpl/storage/GroupedStorage.java
index b49789cfc..cf318e332 100755
--- a/src/main/java/refinedstorage/apiimpl/storage/GroupedStorage.java
+++ b/src/main/java/refinedstorage/apiimpl/storage/GroupedStorage.java
@@ -66,7 +66,9 @@ public class GroupedStorage implements IGroupedStorage {
                 otherStack.stackSize -= stack.stackSize;
 
                 if (otherStack.stackSize == 0) {
-                    stacks.remove(otherStack.getItem(), otherStack);
+                    if (RefinedStorageUtils.getPatternFromNetwork(network, otherStack) == null) {
+                        stacks.remove(otherStack.getItem(), otherStack);
+                    }
                 }
 
                 network.sendStorageToClient();