Some articles that come up today this morning explained that only Visa cards have this feature of enhanced protection where when a transaction takes place, Apple will send information about your purchase information and location to Visa for “fraud prevention”.
Most of the articles that come up in my search results today are simply content farm sites using Apple's own words for fodder. So right now there doesn't seem to be any public information beyond what was provided in Wallet itself.
In any case, there doesn't seem to be much benefit to Apple Wallet
users because a need for additional fraud prevention measures for virtual cards with unique numbers tied to a specific device that require user authentication for use points to some kind of widespread security vulnerability beyond users' control.
it is entirely more plausible that Apple has agreed to give Visa MORE information about purchases to Visa because of some behind the scenes deal, stemming from Visa whining about not getting the same amount of data from ApplePay purchases.
I think it is very possible it is
Visa who is making money off this info. Over the last few years, Visa has made a big push into AI and loss prevention services for merchants and issuers. So a data deal with Apple would, for example, benefit Visa's Advanced Authorization and Risk Manager programs. And if Visa does have some special agreement with Apple, it is also possible Apple agreed to either delay or not allow MC and AMEX to access the data.
Alternatively, Visa could have been the victim of a breach of its authorization systems and is taking steps to re-secure its network. That also could explain why MC and AMEX aren't participating at this time. But given Visa's size and importance to the global financial system as well as the widespread holdings and coverage of its stock, it would be difficult for Visa to obscure such a breach for long.
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ETA: another possibility is the brief visibility of Enhanced Protection for Visa cards is related to Apple changing Apple Cash from Discover to Visa. Debit and preloaded credit cards are frequently used for money laundering and fraud. Visa and Apple, obviously, have a big stake in stopping these illegal activities.
The Apple Cash virtual debit card appears to be switching networks from Discover to Visa, as revealed in some updated images on Apple's website...
www.macrumors.com