Law Times has posted an article about ATD being acquired by Deloitte: http://www.lawtimesnews.com/201401273739/headline-news/accounting-firms-making-serious-noise.
ATD is the largest e-Discovery firm in Toronto that used armies of lawyer subcontractors to do document review, primarily for litigation.
Maybe the acquisition by Deloitte will give ATD the resources they need to fight off new challengers like the US-based EPIQ.
Another player in this industry that I recently learned about is TELUS: http://business.telus.com/enterprise/on/mlb-security. They acquired a digital forensics company a while ago (http://www.digitalwyzdom.com/) and offer litigation services.