Many years ago I had reason to mull over in great detail the question of "why don't banks and government institutions use digital signatures?" (there are many scenarios where this would make processes vastly more easy for users, for the banks themselves, while at the same time making processes more secure. And the common reason for explaining why digital signatures are not used "it's too complex to keep up with key management" only makes sense applied to *users* - banks and similar institutions can easily handle that).

It was interesting to hear people's responses to this question. For example, Mike Hearn basically brushed it off with "they're just dumb" or some flavor thereof, and also pointed out that a bank he had somewhere (California, Switzerland, I forget) actually did offer digital signing. I researched and found one bank in India that claimed to do it but didn't. By chance, a bank in Europe I was using, a year or two later, claimed to offer it *for the users*, and asked me to input my gpg key, which I did, but they never followed up with any functionality at all.

In retrospect I still think my original line of thinking was correct: it didn't pass the lawyers. The most crucial thing about modern digital signatures is their *transferrability*. This means that once a bank signs something, like a statement of account, it can be spread anywhere and is guaranteed to be authentic. This is astoundingly useful *to the bank's clients* but to the bank itself it only represents a liability if they get caught equivocating somehow. Notice how signatures would be useful to the bank at the level of actual transactions (e.g. swift transfers with their peers), but clients are not in the position of actually *transacting* at an equal level; they're just creditors. It's a little like a recent experience of cancelling a UK phone contract: I went through a phone process to cancel it then got charged a bill again; feeling irate, I wanted an email so I could have a record of the conversation I had with their customer service; but they don't offer any email address at all. Only phone or ephemeral chat windows. Same basic thing.