This activity is used to reject a selected authorization step of a purchase requisition. It's done from either Purchase Requisition/Authorization tab or Purchase Requisition Authorization page. The rejection follows similar rules to authorizing a step e.g. you can only reject an authorization step that you are able to authorize and you can only reject the next step if the previous has been authorized. Information about the rejection is stored on the purchase requisition line and remains there until you release the purchase requisition line again e.g. after the necessary changes have been done.