Prime brokers face an information conundrum. To attract hedge fund business, they pledge to uphold the highest standards of client confidentiality. But hedge funds spread business over a number of brokers anyway, effectively keeping their margining limits hidden. So, how can prime brokers get the information they need to risk-manage the relationships with these clients.
A prime broker may try to extrapolate a client's strategy from the business it sees, but there is no way to tell if the results