We received the following from Interactive Brokers Customer Service Today:
“SMART Combinations – Routing Logic Update
Given the level volatility experienced of late and its adverse effect upon the execution of certain combination orders, IB has decided to no longer provide a guarantee with respect to the full execution of stock vs. stock or SMART routed EFP combinations as of 2010-06-02.
Please note, this change will not prevent clients from entering such orders, but rather will expose them to the risk of receiving partial executions, both in terms of leg quantity and balance. In addition, this change will have no impact upon the guarantee provided to SMART routed US Option vs. Option or US Option vs. Stock combination orders.
For additional information, including procedures for acknowledging non-guaranteed combination orders and an example of the risk associated with a partial execution on such orders, please type KB1323 into the search engine on our home page.
Interactive Brokers Customer Service”
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