Correct Amazon MWS flow for item with existing ASIN

Question

I\'m getting started with Amazon MWS and I can\'t seem to see any real information on the correct flow for listing an item as an existing ASIN. Let\'s say for example I am s

Answer 1

It seems in the case of adding a product with an existing ASIN you can actually send a very basic XML request such as this, making sure to include the ASIN:

    

        1.01
        MERCHANT_IDENTIFIER
    
    Product
    false
    
        1
        Update
        
            UNIQUE-TO-ME-1234
            
                ASIN
                B000A0S46M
            
            
                New
            
        
    

Essentially though, from what i've read elsewhere it seems that Amazon will attempt to match a product to an existing ASIN according to the data within the _POST_PRODUCT_DATA_ feed even if an ASIN isn't provided. It will use elements such as title, manufacturer, brand, and other product specific information to compare that to their catalog and determine if it is an existing item or a new one to be added. If you do know it already has an ASIN though you can provide a very simple XML feed as shown above.