Automatically Moving Return Receipts to Folder

I wanted to move the Return Receipts that I receive to my mailbox, to be moved to the folder I created under Folders, named as "Return Receipts".

Tried some agents - did not work.

Tried rules that check for the Subject field containing "RECEIVED:" - did not work.

Then I forgot about it.

Few days back I again recollected of this task. I tried to check some unique fields or field values that differentiates the Return Receipts from the normal Memo.

I tried hard, could not find any unique field.

And suddenly my attention went to the Form field.

Yes, yes, yes. I found it.

Now, the job is to check if the Rules section takes care of the Form field or not. Or is it just for the Subject field only.

And I found it...

Now all my Return Receipts automatically go to the folder that I created, instead of remaining in Inbox.