Over the last few weeks, the highly volatile markets and the way in which capital and margin deposit requirements are calculated for trading futures and options have resulted in a number of firms facing large (and in some cases too large) margin calls. This is an interesting alternative perspective on the events: there may be less of an underlying systematic margin issue than previously thought; and the systems responsible for keeping track of client and own firm margin requirements were incapable of dealing with the volatility and volume of transactions. Whether this is correct or not does not change the fact that there were casualties of the margin calls and volatility. However, it might lead to regulators (and clients) increasing their focus on brokers' and vendors' back-office systems. This will be grist to the FCA's mill, in particular, but the FCA's focus on "operational resilience" is a story for another day.