[Svartalfiar]

The serial numbers of every dollar going in and out of a financail institution is tracked. That is all I will say.

So they know which banks handed out the bills, and which banks had them deposited. They still don't know by whom or what happened with the bills in the intermediary timeframe.

[lurked_for_a_decade]

100% tracing is not necessary. Most bills are spent in one establishemnt, not handed out as change, and deposited that night in the establishments financial institution.

A nice model of a persons shopping and purchase habits and or a businesses clientele can be built from the data. I’m not saying anymore. ;)

The data about who received what, from whom and where it went is just as important as where it didn’t go.