cross-posted from: https://eviltoast.org/post/7440202

Any tech finance folks know what information ATMs get from bank cards?

I found a few articles on how ATMs work:

• https://web.archive.org/web/20240301022054/https://www.nasatm.com/pages/how-do-atms-work
• https://money.howstuffworks.com/personal-finance/banking/atm.htm
• https://web.archive.org/web/20240712072800/https://www.investopedia.com/terms/a/atm.asp

Those articles all skip the crutial details that privacy embracing users would care about: what all info is on the bank card that ATMs have access to and what does the ATM machines do with it?

In principle, I could only imagine that an ATM would get non-personal details like a card №, acct №, card type, and issuing bank – not necessarily the card holder’s name or address. I would like to know for certain though. I need to file a complaint against an ATM network and so it matters who the target of my action knows about me. If I disclose the card number connected to transactions I am complaining about to a mediator who shares that with the ATM operator, could the ATM network/operator then obtain my name and retaliate against me for complaining / whistle blowing by blocking all my cards?