In yesterday's story about the TSX Group merging with Montreal Exchagne (MX), I said TSX had 90 percent market share in equities and suggested that Alpha Group was building a block trading system. Jackie Chung, president of Competitive Metrics, sent me an email this afternoon clarifying the TSX market share figures and explaining the strategy behind Alpha Group (now known as Alpha Trading Systems).

The TSX currently has a 90 percent-plus market share of the "downstairs"
electronic market for Canadian equtiy trading, while the six equity ATS's
together have less than 10 percent of this electronic market at present. On the
other hand, the brokers dominate Canada's "upstairs" market for equity
trading, and this "upstairs" market is currently rather manual. The brokers'
joint effort in launching Alpha Trading Systems (originally announced as
Project Alpha) will make broker internalization more efficient and will
provide an alternative pool of liquidity for Canadian equities. There is no
specific announcement that says Alpha will be an electronic block trading
system. Currently, there are two block electronic trading systems for
Canadian equities - BlockBook (by Perimeter Financial Corp) and Liquidnet
Canada.