Quite often when an exchange has to close due to technical problems, the detail of what exactly happened is kept hushed up (e.g. LSE TradElect glitch in September). But TMX CEO Thomas Kloet has been quite candid with The Globe and Mail about what went wrong with their data feeds this week.

Apparently the cause was a firmware problem on the feed server's processors. This kind of thing can happen, and can't be planned for. But what can be controlled and planned for is how the switchover to a back-up system is handled. In this case, it didn't synch properly, and market participants will quite rightly be calling for a detailed review of all the market operator's business continuity plans.