I've heard (unsure if true) it was to reduce entropy. IE they keep the last 4 di... | Hacker News

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		aaron695 on May 11, 2017 \| parent \| context \| favorite \| on: A crashed advertisement reveals logs of a facial r... I've heard (unsure if true) it was to reduce entropy. IE they keep the last 4 digits of your credit card, combined with a post code you have a unique id.

heywire on May 11, 2017 [–]

Not necessary, most point of sale systems can provide a unique hashed or tokenized version of the account number for analytics and identification purposes.

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