These days e-mail retention (as well as IM logs, recordings of calls etc.) in the financial world is based on rules set by bodies like the SEC and the FSA and r

These days e-mail retention (as well as IM logs, recordings of calls etc.) in the financial world is based on rules set by bodies like the SEC and the FSA and runs to about seven years (at least that's the number I hear thrown about working in that world). Still, if a law suit is brought against the company, you'd generally stop deleting anything until the lawyers give the ok.