Vanessa Countryman
Secretary
Securities and Exchange Commission 100 F Street NE
Washington, DC 20549-1090

Re: Self-Regulatory Organizations; Fixed Income Clearing Corporation; Order Instituting Proceedings To Determine Whether To Approve or Disapprove a Proposed Rule Change To Modify the Calculation of the MBSD VaR Floor To Incorporate a Minimum
Margin Amount (“Order”)

Dear Mrs. Countryman,

SIFMA1 appreciates this additional opportunity to provide feedback on this important proposal2 from the FICC that is the subject of the Order.3

The Order requests that “that interested persons provide written submissions of their views, data, and arguments with respect to the issues identified [therein]”. The Order refers to the FICC’s 2020 proposal to create a minimum margin amount, and for that our comments remain the same. We have included them as an annex to this letter. To summarize our view: we believe that the FICC’s proposed approach could be disruptive to market participants and is not the appropriate way to fix issues that have arisen with the VaR model.

The Order requests comment on how the proposal conforms to various requirements of Section 17A of the Securities and Exchange Act of 1934. We have comments on three of the provisions referenced in the order:

“Section 17A(b)(3)(I) of the Act, which requires that the rules of a clearing agency do not impose any burden on competition not necessary or appropriate in furtherance of the purposes of the Act;”