As we discussed in April 2010, the Investment Industry Regulatory Organization of Canada proposed amendments to UMIR last year that would, among other things, replace the definition of "Market Maker Obligations" with a definition of "Marketplace Trading Obligations" and make various other changes to odd lot and marketplace trading obligations. The OSC and a number of other Canadian securities regulators have now approved the amendments, which become effective today. For more information, see IIROC Notice 11-0251.