Subject: File No. SR-CHX-2016-20
From: Duncan Karcher

March 5, 2017

Dear Sir or Madam,

I write with great interest regarding the impending purchase of the Chicago Stock Exchange by the Casin Group of companies. While I note the concern of other contributors to this group of comments, I can't help but voice my personal concern regarding the vitriol. Certainly any purchase of an entity as important as a stock exchange should duly receive intense scrutiny regarding the investor participants. I trust this is true via the current extensive review by the SEC, and those previous by other regulatory bodies. However, I am struck by some of the anti-Chinese comments that seem to have no basis in fact. Given the intense scrutiny by the professionals within the US government, I want to place on record that I trust your process much more than relying on the ad hominem attacks I read within the comments section. I am a US citizen that has worked for multi-national companies for most of my professional life, each with significant footprints in China. I support investment by Chinese companies into the US, believing that the increased ties through trade will absolutely benefit both countries. I conduct no business with Casin whatsoever and have only a cursory knowledge of their business enterprises. What I do know is that it is not at all productive globally, or to our internal American interests, to succumb to fear of foreign investment by Chinese investors or any other investor group willing to invest in creating new jobs and opportunity in America. I'll leave it to the professionals to ensure that American interests and the rule of law prevail. I support the Chicago Stock Exchange investment by Casin.

Sincerely yours,

Duncan Karcher