Challenges Posed by ATSs
In Canada, prior to the proliferation of ATSs, a security was traded on a centralized exchange and liquidity was located in the exchange’s order book or in the “upstairs market” (where block trades were matched by dealers off-exchange and then executed on the exchange, arguably, the original “dark orders”). ATSs now offer a wide range of options for both order entry and execution. While these offer benefits to investors, they also pose unique challenges in terms of market structure and regulation. At the same time, dealers must adjust to the evolving market and regulatory landscape while striving to serve their clients’ interests. Critics argue that a multiplicity of marketplaces risks leading to market fragmentation, which can, in turn, lead to decreased price discovery (the ability to determine a suitable trading price for a given security) and decreased liquidity (the ability to easily find a counterparty with whom to trade at a reasonable price). Some of the specific issues most often associated with ATSs are discussed below.