Is it possible for a non-consumer (such as a DBA) to return a recurring transaction that has posted to their account, saying they have revoked it? In doing that, it would automatically generate a stop pay for future transactions.

If the revokation is not an option for non-consumers, what is the answer to them when they ask how to get it stopped? Talk to the merchant? So sorry? Need a little guidance here.....

It is possible, and you'd flag their account to block future payments. At my FI we load a stop payment indicating what Return Reason Code to use.

Assuming the SEC code is a CCD you'd use R29 - Corporate Customer Advises Not Authorized (Definition: The RDFI has been notified by the Receiver (non-consumer) a specific transaction has not been authorized by the Receiver.)

Assuming it's another SEC (as we all know that originators sometimes don't use the proper SEC) you'd use R08.

Hopefully this helps!