What a design sprint for a bank has to do that a start-up sprint does not
Same four weeks, same process. What differs is what has to exist at the end.

We run the same four weeks for a Series A start-up and for a private bank. The process is the same. What differs is what has to exist at the end, and getting that wrong is how a good sprint fails to lead anywhere.
A start-up needs a decision. Does this work, is it worth the next quarter of engineering, what do we show investors. The prototype is the deliverable and the argument.
A bank needs a decision and an evidence pack. The prototype is necessary and insufficient. What determines whether anything happens next is whether the InfoSec review can start, whether risk can see the data flows, whether procurement can price a multi-year arrangement. A sprint that produces a working prototype and nothing a risk committee can read has produced a demo.
That is why the governance brief sits in the deliverables rather than being offered as an extra. Not because it matters more than the prototype. Because without it the prototype has nowhere to go.
It is the same reason the sprint runs on sanitised sandbox data. The question a bank has to answer internally is not whether the thing works. It is whether letting it near anything real is a risk somebody is willing to sign for, and that question is easier to answer about a system you have already watched running.
If you want to talk through which of those two your situation actually is, write to hello@windmill.digital, or read what the four weeks cover at /sprint.
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