Subject: File No. SR-CHX-2011-21
From: Michael Bristow
Affiliation: VT Brokers, LLC

July 28, 2011

To whom it may concern,

This letter is in regards to the proposed rule change to Article 20 Rule 9 - Cancellation of Transactions.

In the spirit of the Securities Exchange Act of 1934, if customers are not allowed to cancel the stock portion of a stock/option order, erroneous prints will be left on the tape and it will mislead all market participants. Whenever two parties mutually agree to cancel a transaction, they should be allowed to take down their print. No trade. The CHX current rule set is inadequate regarding this fact and the proposed rule change is a necessary step to ensure investors confidence and faith in the market place.

I vote to allow the proposed rule change.

Best regards,

Michael Bristow
Managing Director
Institutional Stock & Options
220 Montgomery Street | Suite 220 | San Francisco, CA 94104