Certification

I, Jonathan Gans, Chief Executive Officer and President of Ironwood Institutional Multi-Strategy Fund LLC (the “Fund”), certify that:

  1.   The Form N-CSR of the Fund (the “Report”) fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended; and

  2.   The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Fund.

Date: January 6, 2020	/s/ Jonathan Gans
	Jonathan Gans, Chief Executive Officer and President
	(principal executive officer)

Certification

I, Martha Boero, Treasurer of Ironwood Institutional Multi-Strategy Fund LLC (the “Fund”), certify that:

  1.   The Form N-CSR of the Fund (the “Report”) fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended; and

  2.   The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Fund.

Date: January 6, 2020	/s/ Martha Boero
	Martha Boero, Treasurer
	(principal financial officer)