Market Regulation Services Inc. (RS) today issued a notice indicating that the securities regulatory authorities have approved amendments to the Universal Market Integrity Rules to accommodate the introduction of multiple marketplaces trading the same securities.

The amendments, which are effective March 9, include revisions to the provisions governing client priority. These amendments mean that a market participant cannot enter a principal order or non-client order on a marketplace that the participant knows will execute in priority to a client order received by the participant prior to the entry of the principal order. This applies for trades: for the same security; at the same or an inferior price; and, on the same side of the market.

The notice explains that the impact of the amendments include: varying the application of the client priority rule, expanding the exceptions to the client priority rule in certain cases, clarifying the application of various concepts in the trading rules to facilities that may be offered by ATSs and other marketplaces, requiring a minimum 1¢ trading increment for orders entered at 50¢ or more, permitting certain “specialty trades” to execute at non-standard trading increments, limiting the marketplaces on which a client order for 50 standard trading units or less may be exposed, removing access to a marketplace and availability of information as considerations to be taken into account in determining whether a participant has satisfied its “best price” obligation, and, clarifying the factors to be taken into account in determining whether a participant has satisfied its “best execution” and “best price” obligations.