Our merchants do send us all of their transaction information.
If you shop at any of our merchants, it’s possible we’ve been sent some of your transactions in the past,
Mind blown. 
We don’t receive any transaction information for Monzo customers who haven’t signed up to Flux, or for those who have chosen to switch off the Flux integration.
Please confirm if this behaviour is the same for all the banks and companies. I can not find this anywhere in your documentation.
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Thank you for responding.
Wow, your confirmation is very worrying for me. I hoped my suspicion was wrong.
If I have understood you correctly. You have confirmed that the retailers who participate in your service are sending Flux all the transaction information from all their customers to you, in some form, whether they are a Flux user or not!?
So when my friends and family, who are not Flux or Monzo users, purchase something at one of your retailers, they have their data shared with Flux? Without them knowing!?
I’m shocked at this. All the everyday customers can not know the retailers are sharing their transaction data with you. They should know and they should have a say. I can not comprehend how this hasn’t been raised by people, including the retailers.
There are many issues with this and the sharing of sensitive data. Going futher than the unknowns of privacy and the trust placed in a startup having the retailers entire customer transaction data, we’re relying on all the retailers data handling and security. The retailer systems are not uniform. There are many different types. There will be many points of risk if Flux are doing this in a custom fashion with each retailer.
The reality of what happens in order to provide the digital receipt is a great concern for me. Has this concern not been raised before!? I can not find any reference.
I am in the dark. At the least, I would like full breakdown on the information that is being shared between all the parties. What is private, what isn’t and how the process happens.
The FAQ’s say little beyond a few unhelpful lines of ambiguous sentences.