Amendments Respecting Provision of Price Improvement by a Dark Order

Type: Rules Notice> Approval/Implementation
Rule connection:
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Sanka Kasturiarachchi
Policy Counsel, Market Regulation Policy

Executive Summary

On July 25, 2019, the applicable securities regulatory authorities approved amendments to UMIR Rule 6.6 (Amendments) that modify the requirements for Dark Orders1 to provide a better price2 when trading against certain orders. Specifically, the Amendments add a minimum order value of $30,000 in addition to the current threshold of 50 standard trading units (STUs).  Under the Amendments, an order may execute against a Dark Order without receiving a better price only if it is sufficiently large in both volume (over 50 STUs) and value (over $30,000).  

The Amendments were published for comment on December 13, 2018 in IIROC Rules Notice 18-0231 – Rules Notice – Request for Comments – UMIR – Proposed Amendments Respecting Provision of Price Improvement by a Dark Order.  All relevant background information, including the description and impact of the Amendments, is set out in that notice.

Comments Received

We received ten comment letters in response to IIROC Notice 18-0231. Appendix C provides a summary of the public comments received and our responses.

We have not made any revisions to the Amendments, as set out in IIROC Notice 18-0231.


Appendix A – Text of Final UMIR Amendments

Appendix B – Blackline of Amendments to UMIR

Appendix C – Summary of comments received and IIROC’s responses


Participants, marketplaces and vendors will be required to make necessary technology changes to ensure that orders with a notional dollar value of less than $30,000 do not trade against a Dark Order unless the order receives a better price.

The Amendments are effective on February 4, 2020, being 180 days after the publication of this Notice.

MFDA and IIROC have consolidated

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