Wouldn't you prefer encrypted email more than a conversation. You do get a lot of self destructing emails too. And custom protocols included.
And they use phone calls too I presume. Those would also come under the same scrutiny right?
Of course the nature of email makes it difficult to make sure the policy has been enforced.
The standard enforcement protocol is to block all non-company webmail (and other messaging systems) and SMTP so everything runs through corporate Exchange or IM configured with the appropriate retention policy.
I expect that as creating and dealing with wiretap recordings gets easier, we'll see email retention policies extended to voice communications. Currently that only exists for certain highly sensitive positions that interact with the public, AFAIK.
That's not true for banks; they have specific reporting laws to comply with for anything that gets emailed.
> Every member, broker and dealer [...] shall preserve for a period of not less than three years, [...] Originals of all communications received and copies of all communications sent [...] (including inter-office memoranda and communications) [...]